1
dc2481abf
DEMO MANUAL DC2481A-B
DESCRIPTION
LTM4677EY and LTM4650
Step-Down µModule Regulator
with PMBus Power System Management
LTM4677 + 3× LTM4650, 186A
Demonstration circuit 2481A-B is a high efficiency, high
density, µModule® regulator with 4.5V to 16V input range.
The output voltage is adjustable from 0.5V to 1.8V, and it
can supply 186A maximum load current. The demo board
has 1× LT M ®4677 and 3× LTM4650 µModule regulators.
The LTM4677 is a dual 18A or single 36A step-down
regulator with PMBus power system management, and the
LTM4650 is a dual 25A or single 50A step-down regulator.
Please see LTM4677 and LTM4650 data sheets for more
detailed information.
DC2481A-B powers up to default settings and produce
power based on configuration resistors without the need
for any serial bus communication. This allows easy evalu-
ation of the DC/DC converter. To fully explore the extensive
power system management features of the part, download
the GUI software LTpowerPlay® onto your PC and use
L, LT, LTC, LTM, µModule, LTpowerPlay, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
BOARD PHOTO
LT C ’s I2C/SMBus/PMBus dongle DC1613A to connect to
the board. LTpowerPlay allows the user to reconfigure the
part on the fly and store the configuration in EEPROM, view
telemetry of voltage, current, temperature and fault status
GUI Download
The software can be downloaded from:
http://www.linear.com/ltpowerplay
For more details and instructions of LTpowerPlay, please
refer to LTpowerPlay Software GUI.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2481A-B
Figure 1. LTM4677 + 3x LTM4650; 186A DC2481A-B Demo Circuit
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dc2481abf
DEMO MANUAL DC2481A-B
QUICK START PROCEDURE
PERFORMANCE SUMMARY
Specifications are at TA = 25°C
PARAMETER CONDITIONS VALUE
Input Voltage Range 4.5V to 16V
Output Voltage, VOUT0 VIN = 4.5V to 16V, IOUT0 = 0A to 186A 0.5 to 1.8V, Default: 1V
Maximum Output Current, IOUT0 VIN = 4.5V to 16V, VOUT = 0.5V to 1.8V 186A
Typical Efficiency VIN = 12V, VOUT = 1.0V, IOUT = 186A 85.8%
Default Switching Frequency 425kHz
MAXIMUM OUTPUT CURRENT NUMBER OF OUTPUT VOLTAGES
NUMBER OF LTM4677 µMODULE
REGULATORS ON THE BOARD DEMO BOARD NUMBER
Dual 18A 2 1× LTM4677 DC2066A
72A 1 2× LTM4677 DC2143A-A
108A 1 3× LTM4677 DC2143A-B
144A 1 4× LTM4677 DC2143A-C
86A 1 1× LTM4677 (+1×LTM4650) DC2481A-A
186A 1 1× LTM4677 (+3×LTM4650) DC2481A-B
Demonstration circuit 2481A-B is easy to set up to evalu-
ate the performance of the LTM4677EY. Refer to Figure 2
for the proper measurement equipment setup and follow
the procedure below.
1. With power off, connect the input power supply to VIN
(4.5V to 16V) and GND (input return).
2. Connect the 1.0V output load between VOUT0 and GND
(Initial load: no load).
3. Connect the DVMs to the input and outputs. Set default
switch position: SW1: ON; SW2: ON.
4. Turn on the input power supply and check for the proper
output voltages. VOUT0 should be 1.0V ±1%.
5. Once the proper output voltages are established, ad-
just the loads within the operating range and observe
the output voltage regulation, ripple voltage and other
parameters.
6. Connect the dongle and control the output voltages from
the GUI. See “LTpowerPlay Software GUI” for details.
Note: When measuring the output or input voltage ripple,
do not use the long ground lead on the oscilloscope probe.
See Figure 3 for the proper scope probe technique. Short,
stiff leads need to be soldered to the (+) and (–) terminals
of an output capacitor. The probe’s ground ring needs to
touch the (–) lead and the probe tip needs to touch the
(+) lead.
Connecting a PC to DC2481A-B
You can use a PC to reconfigure the power management
features of the LTM4677 such as: nominal VOUT, margin
set points, OV/UV limits, temperature fault limits, sequenc-
ing parameters, the fault log, fault responses, GPIOs and
other functionality. The DC1613A dongle may be plugged
when VIN is present.
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dc2481abf
DEMO MANUAL DC2481A-B
QUICK START PROCEDURE
Figure 2. Proper Measurement Equipment Setup
Figure 3. Measuring Output Voltage Ripple
1mΩ
VOUT0
LOAD (0~186A)
+–
+–
VIN
4.5V TO 16V
dc2481abf F02
+–
+
–
+–
+ –
VOUT GND
COUT
4
dc2481abf
DEMO MANUAL DC2481A-B
QUICK START PROCEDURE
USBtoI2C/PMBus
DongleDC1613A
LTM4677Demo
BoardDC2481A-B
InputPower
Supply
USBCable VIN
12
12
-
12
-
PIN(J7)
Connector
Load
Vout0
Figure 4. Demo Setup with PC
Figure 5. Efficiency vs Load Current at VIN = 12V, VO = 1V and fSW = 425kHz
70
75
80
85
90
0 20 40 60 80 100 120 140 160
dc2481abf F05
180
EFFICIENCY (%)
OUTPUT LOAD CURRENT (A)
Efficiency vs Load Current
VIN = 12V, VO = 1V, fSW = 425kHz
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dc2481abf
DEMO MANUAL DC2481A-B
QUICK START PROCEDURE
Figure 6. Output Voltage VOUT0 vs Load Current at VIN = 12V, VOUT0 = 1V (VOUT0 Range = 0)
Figure 7. Output Voltage Ripple at VIN = 12V, VOUT0 = 1V, IOUT0 = 186A
VOUT0 (20MHz BW) [20mV/DIV]
93A – 140A LOAD STEP
VOUT0 (20MHz BW) [20mV/DIV]
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dc2481abf
DEMO MANUAL DC2481A-B
QUICK START PROCEDURE
Figure 8. Thermal Performance at VIN = 12V, VOUT0 = 1V, IOUT0 = 186A, TA = 23.8°C, Air Flow 400LFM
Figure 9. Current Sharing Performance at VIN = 12V, VOUT0 = 1V
dc2481abf F09
0
10
20
30
40
50
0 40 80 120 160 200
LOAD CURRENT PER PHASE (A)
TOTAL LOAD CURRENT (A)
DC Load Current Sharing
LTM4677
LTM4650_MOD 1
LTM4650_MOD 2
LTM4650_MOD 3
7
dc2481abf
DEMO MANUAL DC2481A-B
LTPOWERPLAY SOFTWARE GUI
Figure 10. LTpowerPlay Main Interface
LTpowerPlay is a powerful Windows based development
environment that supports Linear Technology power sys-
tem management ICs, including the LTM4677, LTC®3880,
LTC3883, LTC2974 and LTC2978. The software supports
a variety of different tasks. You can use LTpowerPlay to
evaluate Linear Technology ICs by connecting to a demo
board system. LTpowerPlay can also be used in an offline
mode (with no hardware present) in order to build a mul-
tichip configuration file that can be saved and reloaded at a
later time. LTpowerPlay provides unprecedented diagnostic
and debug features. It becomes a valuable diagnostic tool
during board bring-up to program or tweak the power
management scheme in a system, or to diagnose power
issues when bringing up rails. LTpowerPlay utilizes the
DC1613A USB-to-SMBus controller to communicate with
one of many potential targets, including the LTM4677, the
LTC3880 and the LTC3883’s demo system, or a customer
board. The software also provides an automatic update
feature to keep the software current with the latest set
of device drivers and documentation. The LTpowerPlay
software can be downloaded from:
http://linear.com/ltpowerplay
To access technical support documents for LTC Digital
Power Products visit Help. View online help on the
LTpowerPlay menu.
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dc2481abf
DEMO MANUAL DC2481A-B
LTPOWERPLAY QUICK START PROCEDURE
The following procedure describes how to use LTpowerPlay
to monitor and change the settings of LTM4677.
1. Download and install the LTPowerPlay GUI:
http://linear.com/ltpowerplay
2. Launch the LTpowerPlay GUI.
a. The GUI should automatically identify the DC2481A-B.
The system tree on the left hand side should look like this:
d. If you want to change the output voltage to a different
value, like 1.5V. In the Config tab, type in 1.5 in the
VOUT_COMMAND box, like this:
b. A green message box shows for a few seconds in the
lower left hand corner, confirming that LTM4677 is
communicating:
c. In the Toolbar, click the “R” (RAM to PC) icon to read
the RAM from the TM4677. This reads the configuration
from the RAM of LTM4677 and loads it into the GUI.
Then, click the “W” (PC to RAM) icon to write these register
values to the LTM4677. After finishing this step, you will
see the output voltage will change to 1.5V.
If the write is successful, you will see the following message:
e. You can save the changes into the NVM. In the tool bar,
click “RAM to NVM” button, as following
f. Save the demo board configuration to a (*.proj) file.
Click the Save icon and save the file. Name it whatever
you want.
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dc2481abf
DEMO MANUAL DC2481A-B
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 18 CIN1, CIN2, CIN4-CIN19 CAP., X5R, 10µF, 35V, 10%,1210 MURATA, GRM32ER6YA106KA12L
2 1 CIN3 CAP., 150µF, 35V, Aluminum Electr., SUN ELECT., 35CE150AX
3 21 COUT1-COUT4, COUT6, COUT9,
COUT10, COUT12, COUT13, COUT15,
COUT16, COUT19, COUT20, COUT23,
COUT24, COUT27, COUT28, COUT31,
COUT32, COUT35, COUT36
4 10 COUT5, COUT7, COUT8, COUT11
COUT18, COUT22, COUT26, COUT30,
COUT34, COUT38
5 1 C5 CAP., CER 4700PF, 16V, X7R, 0603 MURATA, GRM188R71C472KA01D
6 4 C7, C8, C33. C34 CAP., X7R, 0.01µF, 16V, 10%,0603 MURATA, GRM188R71C103KA01D
7 3 C11, C18, C22 CAP., X5R, 2.2µF, 16V, 10%, 0603 MURATA, GRM188R61C225KE15D
8 3 C12, C19, C23 CAP., X7R, 1µF, 16V, 10%, 0603 MURATA, GRM188R71C105KA12D
9 2 C31, C28 CAP., X7R, 1µF, 25V,10%, 1206 MURATA, GRM31MR71E105KA01L
10 1 C25 CAP., X7R, 0.22µF, 25V,10%, 0805 MURATA, GRM21BR71E224KA01L
11 1 C26 CAP., X7R, 0.1µF, 25V,10%, 1206 MURATA, GRM319R71E104KA01J
12 1 C29 CAP., X5R, 1µF, 25V, 10%, 0805 MURATA, GRM216R61E105KA12D
13 1 C27 CAP., X7R, 150pF, 25V, 10%, 0603 Wurth Elektronik, 885012206054
14 1 C30 CAP., X5R, 4.7µF, 10V, 10%, 0603 MURATA, GRM188R61A475KE15D
15 2 D1, D2 LED, GREEN CLEAR 1208 SMD ROHM, SML-010FTT86
16 1 D3 LED, RED CLEAR 1208 SMD ROHM, SML-010VTT86
17 3 Q1, Q3, Q4 MOSFET N-CH 60V, 115MA, SOT-23 FAIRCHILD, 2N7002K
18 1 Q2 MOSFET P-CH 20V, 0.58A, SOT-23 VISHAY, Si2365EDS-T1-GE3 (ALTERNATE
TP0101K-T1-E3)
19 2 Q5, Q6 MOSFET SPEED SRS 30V, 30A, LFPAK RENESAS, RJK0305DPB-02#J0
20 1 Q19 P-Channel 30-V Mosfet DIODES INC., DMP3130L-7
21 1 R25 RES., CHIP, 22.6K, 1%, 0603 VISHAY, CRCW060322K6FKEA
22 22 R4, R8, R23, R31, R32, R34, R37, R41,
R42, R44, R46, R47, R50, R51, R55,
R61, R64, R66, R75, R80, R114, R116
RES., CHIP, 0, 1%, 0603 VISHAY, CRCW06030000Z0EA
23 4 R43, R49, R52, R56 RES., CHIP, 0, 1%, 2010 VISHAY, CRCW20100000Z0EA
24 11 R10, R11, R12, R13, R16, R17, R21,
R58, R77, R94, R118,
RES., CHIP, 10k, 1%, 0603 VISHAY, CRCW060310K0FKEA
25 1 R9 RES., CHIP, 7.15k, 1%, 0603 VISHAY, CRCW06037K15FKEA
26 4 R22, R26, R70, R73 RES., CHIP, 10, 1%, 0603 VISHAY, CRCW060310R0FKEA
27 1 R102 RES., CHIP, 732, 1%, 0603 VISHAY, CRCW0603732RFKEA
28 1 R98 RES., CHIP, 511, 1%, 0603 VISHAY, CRCW0603511RFKEA
29 3 R33, R60, R65 RES., CHIP, 121k, 1%, 0603 VISHAY, CRCW0603121KFKEA
30 3 R40, R63, R68, RES., CHIP, 80.6k, 1%, 0603 VISHAY, CRCW060380K6FKEA
31 1 R35 RES., CHIP, 60.4k, 1%, 0603 VISHAY, CRCW060360K4FKEA
32 1 R36 RES., CHIP, 8.25k, 1%, 0603 VISHAY, CRCW06038K25FKEA
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dc2481abf
DEMO MANUAL DC2481A-B
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
33 1 R19 RES., CHIP, 2.94k, 1%, 0603 VISHAY, CRCW06032K94FKEA
34 3 R45, R84, R85 RES., CHIP, 200, 1%, 0603 VISHAY, CRCW0603200RFKEA
1 R54, RES., CHIP, 2k, 1%, 0603 VISHAY, CRCW06032K00FKEA
35 3 R89, R92, R117 RES., CHIP, 20k, 1%, 0603 VISHAY, CRCW060320K0FKEA
36 2 R76, R115 RES., CHIP, 4.99k, 1%, 0603 VISHAY, CRCW06034K99FKEA
37 1 R86 RES., CHIP, 127, 1%, 0603 VISHAY, CRCW0603127RFKEA
38 1 R87 RES., CHIP, 2, 1%, 0603 VISHAY, CRCW06032R00FKEA
39 1 R88 RES., CHIP, 1M, 1%, 0603 VISHAY, CRCW06031M00FKEA
40 1 R90 RES., CHIP, 154k, 1%, 0603 VISHAY, CRCW0603154KFKEA
41 1 R91 RES., CHIP, 3.3, 1%, 0603 VISHAY, CRCW06033R30FKEA
42 1 R93 RES., CHIP, 681k, 1%, 0603 VISHAY, CRCW0603681KFKEA
43 1 R95 RES., CHIP, 82.5, 1%, 0603 VISHAY, CRCW060382R5FKEA
44 1 R112 RES., CHIP, 15.8k, 1%, 0603 VISHAY, CRCW060315K8FKEA
45 2 R99, R100 RES., CHIP, 0.01, 1%, 2010 VISHAY, WSL2010R0100FEA
46 1 R101 TRIMMING POTENTIOMETER, 5K BOURNS, 3386P-1-502LF
47 1 R103 RES., CHIP, 100k, 1%, 0603 VISHAY CRCW0603100KFKEA
48 1 U1 IC., LTM4677EY LINEAR TECH., LTM4677EY#PBF
49 3 U2, U3, U4 IC., LTM4650EY LINEAR TECH., LTM4650EY#PBF
50 1 U5 IC., LT1801CMS8, MSOP LINEAR TECH., LT1801CMS8#PBF
51 1 U6 IC., EEPROM 2KBIT 400KHZ 8TSSOP MICROCHIP, 24LC025-I/ST
52 1 U7 IC., LTC6992-1, S6-TSOT23 LINEAR TECH., LTC6992CS6-1#PBF
53 1 U8 IC., LT1803IS5, S5-TSOT23 LINEAR TECH., LT1803IS5#PBF
54 1 U9 IC., LT1129CS8-5, S8 LINEAR TECH., LT1129CS8-5#PBF
Additional Demo Board Circuit Components
1 0 C1, C2, C3, C4, C6, C13, COUT14,
COUT17, COUT21, COUT25, COUT29,
COUT33, COUT37, COUT39-COUT50
CAP., OPTIONAL
2 0 C9, C10, C16, C17, C20, C21 CAP., OPTIONAL
3 0 D10 DIODE, OPT
4 0 R1-R3, R5-R7, R14, R15, R18, R20,
R24, R27-R30, R38, R39, R41, R48,
R59, R62, R67, R69, R71, R72, R78,
R79, R96, R97, R104-R109
RES., OPTIONAL
5 0 R39, R62, R67, R69 RES., OPTIONAL
11
dc2481abf
DEMO MANUAL DC2481A-B
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Hardware for Demo-Board Only
1 24 E1-E24 TESTPOINT, TURRET, .062" MILL-MAX, 2308-2-00-80-00-00-07-0
2 2 JP1, JP2 HEADER, 3 PIN 0.079 SINGLE ROW Wurth Elektronik, 62000311121
3 2 XJP1, XJP2 SHUNT, .079" CENTER Wurth Elektronik, 60800213421
4 2 J1, J3 JACK, BANANA KEYSTONE, 575-4
5 4 J2, J4, J5, J6 STUD, TESTPIN PEM, KFH-032-10
6 8 J1, J2, J3, J4, J5, J6 (x2) NUT, BRASS 10-32 ANY, 10-32M/S BR PL
7 4 J1, J2, J3, J4, J5, J6 RING, LUG #10 KEYSTONE, 8205
8 4 J1, J2, J3, J4, J5, J6 WASHER, TIN PLATED BRASS ANY #10, #10EXT BZ TN
9 2 SW1, SW2 CONN, SUB MINIATURE SLIDE SWITCHES C&K., JS202011CQN
10 1 J7 CONN HEADER 12POS 2MM STR DL PCB FCI, 98414-G06-12ULF
11 2 J10, J11 CONN, BNC, 5PINS CONNEX, 112404
12 1 J14 HEADER, 4 PINS, SHROUDED HIROSE, DF3A-4P-2DSA
13 1 J12 CONN RECEPT 2MM DUAL R/A 14POS (F) SULLINS, NPPN072FJFN-RC
14 1 J13 HEADER 14POS 2MM R/A GOLD (M) MOLEX, 87760-1416
15 4 (STAND-OFF) STAND-OFF, NYLON 0.50" tall WURTH ELEKTRONIK, 702935000
16 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT 2481A Rev 1
17 2 STENCIL (TOP & BOTTOM) STENCIL DC2481A
12
dc2481abf
DEMO MANUAL DC2481A-B
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
NOTE: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE 0603.
ALL CAPACITORS ARE 0603.
35V
4.5V - 15V
OPT
1210 1210 1210
0805
0805
1210 1210 1210 1210
1210 1210 1210
0.035 VIA
TESTPOINTS
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
1210
ON
OFF
RUN0
ON
OFF
RUN1
1210
1210
*
1V/186A
*WHEN VIN < 5.75V, SHORT INTVCC TO VIN WITH R7=0 0hm.
1210
VOSNS0+
VOSNS0-
VDD33
SYNC
SHARE_CLK
ALERTB
SCL
SDA
GPIO0B
GPIO1B
ASEL
FREQ_CFG
VOUT0_CFG
VTRIM0_CFG
VOUT1_CFG
VTRIM1_CFG
RUN1
VOSNS0-
VDD25
RUN0
VOSNS1
VIN
VOUT0
VOUT1
VIN
SYNC
SHARE_CLK
ALERTB
SCL
SDA
GPIO0B
GPIO1B
COMP0
COMP1
RUN0
RUN1
VDD33
VOUT0_SNS
VOUT1_SNS
INTVCC
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
16
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
16
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
16
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
Simon T.
PRODUCTION1 04-18-16
__
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
Simon T.
PRODUCTION1 04-18-16
__
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
Simon T.
PRODUCTION1 04-18-16
__
E3
VIN
COUT1
100uF
CIN6
10uF
J5
VOUT0
R16
10K
+
COUT7
470uF
2.5V
D3L
+
COUT11
470uF
2.5V
D2
CIN5
10uF
R8 0
U1
LTM4677EY
VOUT0
A1
VOUT0
A2
VOUT0
A3
VOUT0
D1
ISNS0b-
E1
ISNS0b+
F1
ISNS1b- G1
ISNS1b+ H1
VOUT1 J1
VOUT1 J2
VOUT1 J3
VOUT1 K1
VOUT0
B1
VOUT0
B2
VOUT0
B3
VOUT0
D2
ISNS0a-
E2
ISNS0a+
F2
ISNS1a- G2
ISNS1a+ H2
VOUT1 K2
VOUT1 K3
VOUT1 L1
VOUT1 L2
VOUT0
C1
VOUT0
C2
VOUT0
C3
VOUT0
D3
GND
A4
GND
A6
GND
A7
GND
A8
VOUT1 L3
VOUT1 M1
VOUT1 M2
VOUT1 M3
GND
A9
GND
A10
GND
B4
GND
B5
ASEL G4
FSWPHCFG H4
GND
B6
GND
B7
GND
B8
GND
B9
GPIO0 E4
GPIO1 F4
SNUB0
A5
GND
C4
TSNS0b
C5
TSNS0a
D5
ALERT E5
RUN0 F5
VOUT0CFG G5
VTRIM0CFG H5
TSNS1a J5
TSNS1b K5
GND
C6
SNUB1 M5
GND
C7
GND
C8
GND
C9
SDA D6
SCL E6
RUN1 F6
VOUT1CFG G6
VTRIM1CFG H6
VDD25 J6
WP K6
GND
D4
GND
E3
GND
F3
GND
F10
GND
G3
GND
G10
SYNC E7
GND
M9
GND
M10
SHARE_CLK H7
VDD33 J7
GND
G11
GND
G12
GND
L8 GND
L7
GND
L9
GND
H3
COMP0b
D8
COMP0a
E8
SGND
F7
SGND
F8
COMP1a H8
COMP1b J8
GND
H10
GND
J4
GND
M8
VOSNS0+
D9
VOSNS0-
E9
INTVCC F9
INTVCC G9
VOSNS1 H9
VORB1 J9
GND
J10
GND
L4
GND
L5
GND
K4
SW0
B10
DNC
E11
VORB0+
D10
VORB0-
E10
GND
L6
GND
K7
GND
K8
GND
K9
DNC
C10
SW1 L10
GND
M4
VIN0
B12 VIN0
B11 VIN0
A12 VIN0
A11
DNC
K10
SVIN
F12
GND
M6
DNC
H11
VIN1 H12
VIN1 J11
VIN1 J12
VIN1 K11
VIN0
E12 VIN0
D12 VIN0
D11 VIN0
C12 VIN0
C11
SVIN
F11
GND
M7
VIN1 K12
VIN1 L11
VIN1 L12
VIN1 M11
VIN1 M12
SGND
G7
SGND
G8
GND
D7
R9
1K
R6 OPT
E9
GND0_SNS
R26
10
R3
OPT
R32
0
COUT13
100uF
R7 OPT
C2
OPT
J4
VIN
CIN7
10uF
J3
GND
C7
10nF
E8
VDD25
R22
10
COUT10
100uF
COUT4
100uF
R13
10K
R310
COUT14
OPT
C5
4.7nF
C1
OPT
+
COUT8
470uF
2.5V
D2
P1
R21
10K
R29
OPT
CIN1
10uF
E5
GND1_SNS
R28 OPT
R15
OPT
E6
VDD33
COUT12
100uF
SW2
1
2
3
4
5
6
C4
OPT
R18
OPT
P2
J6
GND
R23
0
P5
C3
OPT
R10
10K
+
COUT5
470uF
2.5V
D2
R17
10K
P6
R20 OPT
R2
OPT
COUT3
100uF
E7
VOUT0_SNS
COUT9
100uF
COUT2
100uF
J2
GND
R5
OPT
R25 18.0K
E2
INTVCC
C8
10nF
+
CIN3
150uF
R14
OPT
R4
0
R1
OPT
E1
VOUT1_SNS
CIN2
10uF
R12
10K
R19
2.94K
R11
10K
P3
P4
CIN4
10uF
R27 OPT
P7
C6
OPT
SW1
1
2
3
4
5
6
J1 VOUT1
R30
OPT
COUT6
100uF
R24 OPT
E4
GND
13
dc2481abf
DEMO MANUAL DC2481A-B
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
1210 1210 1210 1210
1210 1210 1210
1210 1210 1210
OPTIONAL JUMPER FOR SINGLE
OUTPUT CONFIGURATION
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
OPTIONAL OUTPUT SP-CAP
COMP
RUN
COMP
CLKOUT_U1
CLKOUT_U2
VFB
VFB
RUN
INTVCC_U2
INTVCC_U2
EXTVCC
INTVCC_U2
VIN
VOUT0
VOUT0
INTVCC_U2
INTVCC_U2
VOUT0 VOUT1
+5V
EXTVCC
VOUT0
VOUT1
VIN
SYNC
CLKOUT_U1
CLKOUT_U2
+5V
COMP0
COMP
GPIO0B
COMP
COMP
VFB
VFB
COMP0 COMP1
RUN0RUN1
GPIO0B GPIO1B
RUN
RUN0
RUN
CLKOUT_U1
TRACK
TRACK
VOUT0_SNS VOUT1_SNS
INTVCC
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
26
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
26
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
26
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
R106 OPT
R36
8.25k
R37
0
R59
OPT
R39
(OPT)
R58
10K
C11
2.2uF
10V
R45
200
R34
0
C10
(OPT)
C12
1uF
10V
P9
P11
R43 0 2010
R51
0
R52 0 2010
COUT19
100uF
R118 10K
U5
LT1801CMS8
OUTA
1
-IN A
2
+IN A
3
V-
45 +IN B 5
6 -IN B 6
7 OUT B 7
8V+ 8
+
COUT22
470uF
D2
2.5V
C13
OPT
R35
60.4k
R38 OPT
CIN8
10uF
Q1
2N7002A
2 3
1
COUT15
100uF
R42 0
CIN10
10uF
R117 20K
COUT21
OPT
R109
OPT
R48
OPT
R50 0
COUT16
100uF
R41
0
COUT20
100uF
R40
80.6K
1%
P10
R105
OPT
R33
121K
1%
R49 0 2010
R55
0
+
COUT18
470uF
D2
2.5V
C9
(OPT)
R47 0
R116 0
R56 0 2010
R104
OPT
+
COUT50
470uF
D2
2.5V
R46
0
U2
LTM4650EY
VOUT1 A1
VOUT1 A2
VOUT1 A3
VOUT1 A4
VOUT1 A5
VOUT1 B1
VOUT1 B2
VOUT1 B3
VOUT1 B4
VOUT1 B5
VOUT1 C1
VOUT1 C2
VOUT1 C3
VOUT1 C4
VFB1 D5
SW1 G2
PGOOD1 G9
COMP1 E6
RUN1 F5
TRACK1 E5
VOUTS1 C5
VOUT2 A8
VOUT2 A9
VOUT2 A10
VOUT2 A11
VOUT2 A12
VOUT2 B8
VOUT2 B9
VOUT2 B10
VOUT2 B11
VOUT2 B12
VOUT2 C9
VOUT2 C10
VOUT2 C11
VOUT2 C12
VFB2 D7
SW2 G11
PGOOD2 G8
COMP2 E7
RUN2 F9
TRACK2 D8
VOUTS2 C8
VIN
M2
VIN
M3
VIN
M4
VIN
M5
VIN
M6
VIN
M7
VIN
M8
VIN
M9
VIN
M10
VIN
M11
VIN
L2
VIN
L3
VIN
L4
VIN
L5
VIN
L6
VIN
L7
VIN
L8
VIN
L9
VIN
L10
VIN
L11
VIN K2
VIN K3
VIN K4
VIN K9
VIN K10
VIN K11
VIN J2
VIN J3
VIN J4
VIN J9
VIN J10
VIN J11
GND
A6
GND
A7
GND
B6
GND
B7
GND
D1
GND
D2
GND
D3
GND
D4
GND
D9
GND
D10
GND
D11
GND
D12
GND
E1
GND
E2
GND
E3
GND
E4
GND
E10
GND
E11
GND
E12
GND
F1
GND
F2
GND
F3
GND
F10
GND
F11
GND
F12
GND
G1
GND
G3
GND
G10
GND
G12
GND
H1
GND
H2
GND
H3
GND
H4
GND
H5
GND
H6
GND
H7
GND
H9
GND
H10
GND
H11
GND
H12
GND
M12 GND
M1 GND
L12
GND
J1
GND
J5
GND
J8
GND
J12
GND
K1
GND
K5
GND
K6
GND
K7
GND
K8
GND
K12
GND
L1
SGND
C7
SGND
D6
SGND
F6
SGND
F7
SGND
G6
SGND
G7
FSET
C6
PHASMD
G4
DIFFP E8
DIFFN E9
CLKOUT G5
MODE-PLLIN F4
TEMP J6
INTVCC
H8
EXTVCC
J7
DIFFOUT F8
COUT17
OPT
P8
+
COUT44
470uF
D2
2.5V
+
COUT39
470uF
D2
2.5V
+
COUT45
470uF
D2
2.5V
+
COUT40
470uF
D2
2.5V
+
COUT46
470uF
D2
2.5V
+
COUT41
470uF
D2
2.5V
R54
2K
+
COUT47
470uF
D2
2.5V
+
COUT42
470uF
D2
2.5V
+
COUT48
470uF
D2
2.5V
+
COUT43
470uF
D2
2.5V
+
COUT49
470uF
D2
2.5V
CIN11
10uF
R44 0
CIN9
10uF
14
dc2481abf
DEMO MANUAL DC2481A-B
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
1210 1210 1210
1210 1210 1210
1210 1210 1210 1210
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
COMP
RUN
COMP
CLKOUT_U2
CLKOUT_U3
VFB
RUN
VFB
VOUT0
VOUT0
INTVCC_U3
INTVCC_U3
EXTVCC
INTVCC_U3
VIN
RUN
COMP
VFB
CLKOUT_U2
CLKOUT_U3
COMP
VFB
RUN
TRACK
TRACK
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
36
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
36
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
36
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
CIN15
10uF COUT23
100uF
R107
OPT
COUT24
100uF
CIN12
10uF
COUT27
100uF
+
COUT30
470uF
2.5V
D2
COUT28
100uF
CIN13
10uF
R61
0
C18
2.2uF
10V
P13
C17
(OPT)
P15
COUT29
OPT
R64
0
R60
121K
1%
+
COUT26
470uF
2.5V
D2
R63
80.6K
1%
COUT25
OPT
CIN14
10uF
U3
LTM4650EY
VOUT1 A1
VOUT1 A2
VOUT1 A3
VOUT1 A4
VOUT1 A5
VOUT1 B1
VOUT1 B2
VOUT1 B3
VOUT1 B4
VOUT1 B5
VOUT1 C1
VOUT1 C2
VOUT1 C3
VOUT1 C4
VFB1 D5
SW1 G2
PGOOD1 G9
COMP1 E6
RUN1 F5
TRACK1 E5
VOUTS1 C5
VOUT2 A8
VOUT2 A9
VOUT2 A10
VOUT2 A11
VOUT2 A12
VOUT2 B8
VOUT2 B9
VOUT2 B10
VOUT2 B11
VOUT2 B12
VOUT2 C9
VOUT2 C10
VOUT2 C11
VOUT2 C12
VFB2 D7
SW2 G11
PGOOD2 G8
COMP2 E7
RUN2 F9
TRACK2 D8
VOUTS2 C8
VIN
M2
VIN
M3
VIN
M4
VIN
M5
VIN
M6
VIN
M7
VIN
M8
VIN
M9
VIN
M10
VIN
M11
VIN
L2
VIN
L3
VIN
L4
VIN
L5
VIN
L6
VIN
L7
VIN
L8
VIN
L9
VIN
L10
VIN
L11
VIN K2
VIN K3
VIN K4
VIN K9
VIN K10
VIN K11
VIN J2
VIN J3
VIN J4
VIN J9
VIN J10
VIN J11
GND
A6
GND
A7
GND
B6
GND
B7
GND
D1
GND
D2
GND
D3
GND
D4
GND
D9
GND
D10
GND
D11
GND
D12
GND
E1
GND
E2
GND
E3
GND
E4
GND
E10
GND
E11
GND
E12
GND
F1
GND
F2
GND
F3
GND
F10
GND
F11
GND
F12
GND
G1
GND
G3
GND
G10
GND
G12
GND
H1
GND
H2
GND
H3
GND
H4
GND
H5
GND
H6
GND
H7
GND
H9
GND
H10
GND
H11
GND
H12
GND
M12 GND
M1 GND
L12
GND
J1
GND
J5
GND
J8
GND
J12
GND
K1
GND
K5
GND
K6
GND
K7
GND
K8
GND
K12
GND
L1
SGND
C7
SGND
D6
SGND
F6
SGND
F7
SGND
G6
SGND
G7
FSET
C6
PHASMD
G4
DIFFP E8
DIFFN E9
CLKOUT G5
MODE-PLLIN F4
TEMP J6
INTVCC
H8
EXTVCC
J7
DIFFOUT F8
P12
C16
(OPT)
R62
(OPT)
P14
C19
1uF
10V
15
dc2481abf
DEMO MANUAL DC2481A-B
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
1210 1210 1210
1210 1210 1210
1210 1210 1210 1210
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
COMP
RUN
COMP
CLKOUT_U3
CLKOUT_U4
VFB
VFB
RUN
VOUT0
VOUT0
INTVCC_U4
INTVCC_U4
EXTVCC
INTVCC_U4
VIN
RUN
COMP
VFB
CLKOUT_U3
CLKOUT_U4
COMP
VFB
RUN
TRACK
TRACK
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
46
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
46
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
46
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
R65
121K
1%
+
COUT34
470uF
2.5V
D2
COUT37
OPT
COUT33
OPT
R69
(OPT)
C20
(OPT)
C21
(OPT)
C23
1uF
10V
CIN16
10uF
COUT36
100uF
COUT31
100uF
P17
R68
80.6K
1%
COUT32
100uF
COUT35
100uF
U4
LTM4650EY
VOUT1 A1
VOUT1 A2
VOUT1 A3
VOUT1 A4
VOUT1 A5
VOUT1 B1
VOUT1 B2
VOUT1 B3
VOUT1 B4
VOUT1 B5
VOUT1 C1
VOUT1 C2
VOUT1 C3
VOUT1 C4
VFB1 D5
SW1 G2
PGOOD1 G9
COMP1 E6
RUN1 F5
TRACK1 E5
VOUTS1 C5
VOUT2 A8
VOUT2 A9
VOUT2 A10
VOUT2 A11
VOUT2 A12
VOUT2 B8
VOUT2 B9
VOUT2 B10
VOUT2 B11
VOUT2 B12
VOUT2 C9
VOUT2 C10
VOUT2 C11
VOUT2 C12
VFB2 D7
SW2 G11
PGOOD2 G8
COMP2 E7
RUN2 F9
TRACK2 D8
VOUTS2 C8
VIN
M2
VIN
M3
VIN
M4
VIN
M5
VIN
M6
VIN
M7
VIN
M8
VIN
M9
VIN
M10
VIN
M11
VIN
L2
VIN
L3
VIN
L4
VIN
L5
VIN
L6
VIN
L7
VIN
L8
VIN
L9
VIN
L10
VIN
L11
VIN K2
VIN K3
VIN K4
VIN K9
VIN K10
VIN K11
VIN J2
VIN J3
VIN J4
VIN J9
VIN J10
VIN J11
GND
A6
GND
A7
GND
B6
GND
B7
GND
D1
GND
D2
GND
D3
GND
D4
GND
D9
GND
D10
GND
D11
GND
D12
GND
E1
GND
E2
GND
E3
GND
E4
GND
E10
GND
E11
GND
E12
GND
F1
GND
F2
GND
F3
GND
F10
GND
F11
GND
F12
GND
G1
GND
G3
GND
G10
GND
G12
GND
H1
GND
H2
GND
H3
GND
H4
GND
H5
GND
H6
GND
H7
GND
H9
GND
H10
GND
H11
GND
H12
GND
M12 GND
M1 GND
L12
GND
J1
GND
J5
GND
J8
GND
J12
GND
K1
GND
K5
GND
K6
GND
K7
GND
K8
GND
K12
GND
L1
SGND
C7
SGND
D6
SGND
F6
SGND
F7
SGND
G6
SGND
G7
FSET
C6
PHASMD
G4
DIFFP E8
DIFFN E9
CLKOUT G5
MODE-PLLIN F4
TEMP J6
INTVCC
H8
EXTVCC
J7
DIFFOUT F8
+
COUT38
470uF
2.5V
D2
R66
0
P19
E10
CLKOUT
R67
(OPT)
CIN17
10uF
R108
OPT
P16
C22
2.2uF
10V
CIN18
10uF
P18
CIN19
10uF
16
dc2481abf
DEMO MANUAL DC2481A-B
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
ALL PARTS ON THIS PAGE ARE FOR DEMO ONLY, NOT NEEDED IN CUSTOMER DESIGN
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
GPIO0 GPIO1
ALERTB
J1, MALE, CONN HEADER 14POS 2MM R/A GOLD, Molex Connector Corp. 87760-1416
J2, FEMALE, CONN RECEPT 2MM DUAL R/A 14POS, Sullins Conn. NPPN072FJFN-RC
TO DC1613A
PSM STACKING CONNECTORS:
OPTIONAL CIRCUIT FOR PROGRAMMING
WITHOUT VIN
1206
TO DC2086A
AUXVCC
EEWP
EESDA
EESCL
AUX3V4
3V3 3V3 3V3
3V3
VIN
3V3 VDD33
VIN
3V3
GPIO0B GPIO1B
ALERTB
VDD33
ALERTB SDA SCL
RUN0
RUN1
GPIO1B
GPIO0B
SYNC
SHARE_CLK
VDD33
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
56
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
56
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
56
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
C34
10nF
J12 DEMO HEADER (F)
FAULTB 1
CTRL 2
ALERTB 3
SDA 4
SHARE_CLK 5
SCL 6
RESETB 7
AUXP 8
UNUSED 9
UNUSED 10
GND 11
GND 12
12V 13
12V 14
R72 OPT
U6
24LC025-I/ST
A0
1
A1
2
A2
3
VSS
4SDA 5
SCL 6
WP 7
VCC 8
R74 OPT
E12
ALERTB
D2 GREEN
R77 10K
J14
AUX3V4 4
SCL 3
GND 2
1
SDA
E11
GPIO1B
J13 DEMO HEADER (M)
FAULTB
1
CTRL
2
ALERTB
3
SDA
4
SHARE_CLK
5
SCL
6
RESETB
7
AUXP
8
UNUSED
9
UNUSED
10
GND
11
GND
12
12V
13
12V
14
D8
21
J7
AUXP 1
SDA 2
GND 3
SCL 4
LGKPWR 5
ALERTB 6
GPIO_1 7
OUTEN_0 8
OUTEN_1 9
GND 10
AUXSCL 11
AUXSDA 12
E25
AUXP
E17
SGND
R70
10
R85
200
R86
127
E15
SHARE_CLK
R81 OPT
R111
OPT
R83
OPT
R78
OPT
R80 0
Q3
2N7002A
2 3
1
R71
OPT
R75
0
R113
OPT
R73
10
E21
RUN1
D3 RED
E14
SCL
C33
10nF
E13
SDA
D4
OPT
R115
4.99K
Q4
2N7002A
2 3
1
E16
SYNC
R114 0
E22
SGND
R112
15.8k
C32
100nF
D1
GREEN
E18
GPIO0B
D5
OPT
Q2
TP0101K
23
1
R82
OPT
Q19
DMP3130L-7
23
1
E19
RUN0
R110
OPT
R84
200
R76
4.99K
R79 OPT
17
dc2481abf
DEMO MANUAL DC2481A-B
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
ON
OFF
PULSE
BIAS
ALL PARTS ON THIS PAGE ARE FOR DEMO ONLY, NOT NEEDED IN CUSTOMER DESIGN
OPT
2010 2010
OPT
DYNAMIC LOAD CIRCUIT
BLEEDER LOADS
70Hz, 3% Duty Cycle
INT EXT
1%
1%
0805
IOUT
TST
VOUT0
µMODULE REGULATOR WITH POWER SYSTEM MANAGEMENT
VIN
VOUT0 VOUT1
VOUT0
+5V
+5V
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
66
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
66
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. SCALE = NONE
www.linear.com
1
Monday, April 18, 2016
66
HIGH EFFICIENCY, POLY-PHASE, DC/DC STEP-DOWN
HZ
ST
B
LTM4677EY / LTM4650EY
DEMO CIRCUIT 2481A-A/B
R88
1M
Q6
RJK0305DPB
1
2
5
3
4
R90 154K
R100
0.01
R91 3.3
E24
GND
E23
EXT PULSE
JP1
1
2
3
J11
1
2
3
4
5
R93
681K
U9
LT1129CS8-5
OUTPUT 1
SENSE/ADJ 2
GND 3
NC 4
SHDN
5
GND
6
GND
7
VIN
8
JP2
1
2
3
R89
20K
R87
2C25
0.22uF
J10
1
2
3
4
5
C31
1uF
C26
0.1uF
R99
0.01
R92
20K
U7
LTC6992-1
MOD
1
GND
2
SET
3DIV 4
V+ 5
OUT 6
Q5
RJK0305DPB
1
2
5
3
4
R103
100K
C29
1uF
R102
732
R94
10K
C30
4.7uF
R95 82.5
R96 R98
511
U8
LT1803IS5
VOUT 1
V-
2
+IN
3-IN 4
V+
5
C27
150pF
R101
5K
R97
C28
1uF
18
dc2481abf
DEMO MANUAL DC2481A-B
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ●FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2016
LT 0616 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application
engineer.
Mailing Address:
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Copyright © 2004, Linear Technology Corporation