_______________General Description
The MAX619 step-up charge-pump DC-DC converter
delivers a regulated 5V ±4% output at 50mA over tem-
perature. The input voltage range is 2V to 3.6V (two
battery cells).
The complete MAX619 circuit fits into less than 0.1in2of
board space because it requires only four external
capacitors: two 0.22µF flying capacitors, and 10µF
capacitors at the input and output.
Low operating supply current (150µA max) and low
shutdown supply current (1µA max) make this device
ideal for small, portable, and battery-powered applica-
tions. When shut down, the load is disconnected from
the input.
The MAX619 is available in 8-pin DIP and SO packages.
________________________Applications
Two Battery Cells to 5V Conversion
Local 3V-to-5V Conversion
Portable Instruments & Handy-Terminals
Battery-Powered Microprocessor-Based Systems
5V Flash Memory Programmer
Minimum Component DC-DC Converters
Remote Data-Acquisition Systems
Compact 5V Op-Amp Supply
Regulated 5V Supply from Lithium Backup Battery
Switching Drive Voltage for MOSFETs in
Low-Voltage Systems
____________________________Features
♦Regulated 5V ±4% Charge Pump
♦Output Current Guaranteed over Temperature
20mA (VIN ≥2V)
50mA (VIN ≥3V)
♦2V to 3.6V Input Range
♦No Inductors; Very Low EMI Noise
♦Ultra-Small Application Circuit (0.1in2)
♦Uses Small, Inexpensive Capacitors
♦500kHz Internal Oscillator
♦Logic-Controlled 1µA Max Shutdown
Supply Current
♦Shutdown Disconnects Load from Input
♦8-Pin DIP and SO Packages
_______________Ordering Information
* Dice are specified at T
A
= +25°C.
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
________________________________________________________________
Maxim Integrated Products
1
1
2
3
4
8
7
6
5
MAX619
DIP/SO
C1+
IN
OUT
C2+
C1-
SHDN
GND
C2-
TOP VIEW
__________________Pin Configuration
MAX619
OUT
C2+
C2-
IN
SHDN
C1+
C1-
INPUT
2V to 3.6V
ON/OFF
0.22µF
OUTPUT
5V, 20mA
10µF10µF
0.22µF
GND
__________Typical Operating Circuit
19-0227; Rev 2; 5/96
EVALUATION KIT MANUAL
FOLLOWS DATA SHEET
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
PART TEMP. RANGE PIN-PACKAGE
MAX619CPA 0°C to +70°C 8 Plastic DIP
MAX619CSA 0°C to +70°C 8 SO
MAX619C/D 0°C to +70°C Dice*
MAX619EPA -40°C to +85°C 8 Plastic DIP
MAX619ESA -40°C to +85°C 8 SO
MAX619MJA -55°C to +125°C 8 CERDIP
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
2 ________________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN = 2V to 3.6V, C1 = C2 = 0.22µF, C3 = C4 = 10µF, TA= TMIN to TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Note 1: The MAX619 is not short-circuit protected.
PARAMETER SYMBOL MIN TYP MAX UNITS
No-Load Supply Current 75 170 µA
0.02 1
Shutdown Supply
Current 10 µA
82
Input Voltage VIN 2 3.6 V
82
80
Efficiency Eff %
Switching Frequency 500 kHz
VIH 0.7 x VIN
SHDN Input Threshold VIL 0.4 V
±1
SHDN Input Current IIH ±10 µA
CONDITIONS
VIN = 3V, IOUT = 30mA
2V ≤VIN ≤3.6V, IOUT = 0mA
VIN = 2V, IOUT = 20mA
2V
≤
V
IN
≤
3.6V, I
OUT
= 0mA,
VSHDN = VIN
VIN = 3V, IOUT = 20mA
At full load
VSHDN = VIN
VIN to GND ............................................................-0.3V to +5.5V
VOUT to GND.........................................................-0.3V to +5.5V
SHDN to GND..............................................-0.3V to (VIN + 0.3V)
IOUT Continuous (Note 1)..................................................120mA
Continuous Power Dissipation (TA= +70°C)
Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW
SO (derate 5.88mW/°C above +70°C).........................471mW
CERDIP (derate 8.00mW/°C above +70°C).................640mW
Operating Temperature Ranges
MAX619C_ _ .......................................................0°C to +70°C
MAX619E_ _ ....................................................-40°C to +85°C
MAX619MJA..................................................-55°C to +125°C
Storage Temperature Range.............................-65°C to +165°C
Lead Temperature (soldering, 10sec).............................+300°C
MAX619C/E
MAX619M
MAX619C/E
MAX619M
IIN
2.0V ≤VIN ≤3.6V, 0mA ≤IOUT ≤20mA
3.0V ≤VIN ≤3.6V, 0mA ≤IOUT ≤50mA, MAX619C
3.0V ≤VIN ≤3.6V, 0mA ≤IOUT ≤45mA, MAX619E
Output Ripple VRIPPLE 100 mVNo load to full load
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
3.0V ≤VIN ≤3.6V, 0mA ≤IOUT ≤40mA, MAX619M
Output Voltage VOUT 4.8 5.0 5.2 V
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
________________________________________________________________________________________
3
TOP TRACE: OUTPUT CURRENT, 0mA to 25mA, 10mA/div
BOTTOM TRACE: OUTPUT VOLTAGE, 5mV/div, AC-COUPLED
2ms/div
LOAD-TRANSIENT RESPONSE
RLOAD = 250Ω, VOUT = 5V, IOUT = 20mA
TOP TRACE: VIN = 2V to 3V, 1V/div
BOTTOM TRACE: OUTPUT VOLTAGE, 50mV/div, AC-COUPLED
2ms/div
LINE-TRANSIENT RESPONSE (IOUT = 20mA)
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
60 1 10 100
EFFICIENCY vs. OUTPUT CURRENT
AND INPUT VOLTAGE
IOUT (mA)
EFFICIENCY (%)
65
70
75
80
85
90
VIN = 1.8V
VIN = 3.0V
VIN = 2.0V
VIN = 3.3V
VIN = 3.6V
VIN = 2.4V
VIN = 2.7V
00
INPUT CURRENT vs. OUTPUT CURRENT
IOUT (mA)
IIN (mA)
10 20 30 40 50 60 70 80 90 100
20
40
60
80
100
120
140
160
180
200
VIN IOUT
MAX
A
B
C
D
E
F
G
1.8
2.0
2.4
2.7
3.0
3.6
3.3
18
36
41
64
72
94
100
A
BC
D
E
G
F
NO-LOAD INPUT CURRENT
vs. INPUT VOLTAGE
VIN (V)
IIN (µA)
1.5 2.0 2.5 3.0 3.5 4.0 4.5
0.01
0.1
1.0
10
100
1000
SHDN = VIN
SHDN = 0V
4.75
4.80
1 10 100
OUTPUT VOLTAGE vs. OUTPUT CURRENT
IOUT (mA)
VOUT (V)
4.85
4.90
4.95
5.00
5.05
VIN = 1.8V
VIN = 2.0V
VIN = 3.3V
VIN = 2.4V, 2.7V
= 3.6V
VIN = 3.6V
VIN = 3.0V
OUTPUT VOLTAGE vs. INPUT VOLTAGE
VIN (V)
VOUT (V)
2.01.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
4.94
4.96
4.98
5.00
5.02
5.04
5.06
IOUT = 20mA
EFFICIENCY vs. INPUT VOLTAGE
VIN (V)
EFFICIENCY (%)
1.5
60
65
70
75
80
85
90 IOUT = 10mA
2.0 2.5 3.0 3.5 4.0
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
4 ________________________________________________________________________________________
_______________Detailed Description
Operating Principle
The MAX619 provides a regulated 5V output from a 2V
to 3.6V (two battery cells) input. Internal charge pumps
and external capacitors generate the 5V output, elimi-
nating the need for inductors. The output voltage is
regulated to 5V ±4% by a pulse-skipping controller that
turns on the charge pump when the output voltage
begins to droop.
To maintain the greatest efficiency over the entire input
voltage range, the MAX619’s internal charge pump
operates as a voltage doubler when VIN ranges from
3.0V to 3.6V, and as a voltage tripler when VIN ranges
from 2.0V to 2.5V. When VIN ranges from 2.5V to 3.0V,
_____________________Pin Description
the MAX619 switches between doubler and tripler
mode on alternating cycles, making a 2.5 x VIN charge
pump. To further enhance efficiency over the input
range, an internal comparator selects the higher of VIN
or VOUT to run the MAX619’s internal circuitry.
Efficiency with VIN = 2V and IOUT = 20mA is typically
80%.
Figure 1 shows a detailed block diagram of the
MAX619. In tripler mode, when the S1 switches close,
the S2 switches open and capacitors C1 and C2
charge up to VIN. On the second half of the cycle, C1
and C2 are connected in series between IN and OUT
when the S1 switches open and the S2 switches close,
as shown in Figure 1. In doubler mode, only C2 is
used.
During one oscillator cycle, energy is transferred from
the input to the charge-pump capacitors, and then
from the charge-pump capacitors to the output capaci-
tor and load. The number of cycles within a given time
frame increases as the load increases or as the input
supply voltage decreases. In the limiting case, the
charge pumps operate continuously, and the oscillator
frequency is nominally 500kHz.
Shutdown Mode
The MAX619 enters low-power shutdown mode when
SHDN is a logic high. SHDN is a CMOS-compatible
input. In shutdown mode, the charge-pump switching
action is halted, OUT is disconnected from IN, and
VOUT falls to 0V. Connect SHDN to ground for normal
operation. When VIN = 3.6V, VOUT typically reaches
5V in 0.5ms under no-load conditions after SHDN goes
low.
FUNCTIONNAMEPIN
Negative Terminal for C1C1-8
Active-High CMOS Logic-Level Shutdown InputSHDN7
GroundGND6
Negative Terminal for C2C2-5
Positive Terminal for C2C2+4
+5V Output Voltage. VOUT = 0V when in
shutdown mode.
OUT3
Input Supply VoltageIN2
Positive Terminal for C1C1+1
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
________________________________________________________________________________________ 5
C3
10µF
C2
0.22µF
P
P
C1
0.22µF
C2-
C1+
S1D
C1-
S1C
S2C
S2B
S1B
S1A
S2A
IN
SWITCH
CONTROL
BUS
VIN/VOUT
SD
FB
IN
IC
POWER
*
*
GND
SWITCHES SHOWN IN TRIPLER MODE, DISCHARGE CYCLE
CONTROL
LOGIC
10µF
OUT
VREF
SHDN
C2+
MAX619
C4
Figure 1. Block Diagram
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
6 ________________________________________________________________________________________
Table 1. Capacitor Suppliers
* Note: (SM) denotes surface-mount component, (TH) denotes through-hole component.
__________Applications Information
Capacitor Selection
Charge-Pump Capacitors C1 and C2
The values of charge-pump capacitors C1 and C2 are
critical to ensure adequate output current and avoid
excessive peak currents. Use values in the range of
0.22µF to 1.0µF. Larger capacitors (up to 50µF) can
be used, but larger capacitors will increase output rip-
ple. Ceramic or tantalum capacitors are recommend-
ed.
Input and Output Capacitors, C3 and C4
The type of input bypass capacitor (C3) and output fil-
ter capacitor (C4) used is not critical, but it does affect
performance. Tantalums, ceramics, or aluminum elec-
trolytics are suggested. For smallest size, use Sprague
595D106X0010A2 surface-mount capacitors, which
measure 3.7mm x 1.8mm (0.146in x 0.072in). For low-
est ripple, use large, low effective-series-resistance
(ESR) ceramic or tantalum capacitors. For lowest cost,
use aluminum electrolytic or tantalum capacitors.
Figure 2 shows the component values for proper oper-
ation using minimal board space. The input bypass
capacitor (C3) and output filter capacitor (C4) should
both be at least 10µF when using aluminum electrolyt-
ics or Sprague’s miniature 595D series of tantalum chip
capacitors.
When using ceramic capacitors, the values of C3 and
C4 can be reduced to 2µF and 1µF, respectively. If the
input supply source impedance is very low, C3 may not
be necessary.
Many capacitors exhibit 40% to 50% variation over
temperature. Compensate for capacitor temperature
coefficient by selecting a larger nominal value to
ensure proper operation over temperature. Table 1 lists
capacitor suppliers.
MAX619
C4
10µF
IN
C1+
C1–
OUT
SHDN
C2+
C2–
GND
7
4
5
6
2
1
8
3
C3
10µF
2
CELLS
C1
0.22µF
C2
0.22µF
5V ±4%
@ 20mA
Figure 2. Two-Cell to 5V Application Circuit
10µF tantalum (SM)
595D106X0010A2
(603) 224-1430
(207) 324-7223
(603) 224-1961
(207) 327-4140
Sprague Electric
(smallest size)
0.1µF ceramic (TH)
RPE121Z5U104M50V
(814) 238-0490(814) 237-1431Murata Erie 1.0µF ceramic (TH)
RPI123Z5U105M50V 0.22µF ceramic (SM)
GRM42-6Z5U22M50 0.1µF ceramic (SM)
GRM42-6Z5U10M50 CAPACITOR TYPE*CAPACITORFAX NUMBERPHONE NUMBERSUPPLIER
MAX619
Regulated 5V Charge-Pump
DC-DC Converter
________________________________________________________________________________________ 7
Layout Considerations
The MAX619’s high oscillator frequency makes good
layout important. A good layout ensures stability and
helps maintain the output voltage under heavy loads.
For best performance, use very short connections to
the capacitors.
Paralleling Devices
Two MAX619s can be placed in parallel to increase
output drive capability. The IN, OUT, and GND pins
can be paralleled, but C1 and C2 pins cannot. The
input bypass capacitor and output filter capacitor are,
to some extent, shared when two circuits are paral-
leled. If the circuits are physically close together, it
may be possible to use a single bypass and a single
output capacitor, each with twice the value of the single
circuit. If the MAX619s cannot be placed close togeth-
er, use separate bypass and output capacitors. The
amount of output ripple observed will determine
whether single input bypass and output filter capacitors
can be used.
___________________Chip Topography
C1+ C1-
SHDN
GND
0.115”
(2.921mm)
IN
OUT
C2+
C2-
0.072”
(1.828mm)
TRANSISTOR COUNT: 599;
SUBSTRATE CONNECTED TO GND.
MAX619
IN OUT
GND
INPUT 5V, 40mA
MAX619
IN OUT
GND
Figure 3. Paralleling Two MAX619s
