1
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
–
+
R6
499Ω
LT6202
V
S+
V
OUT
IN
+
IN
–
+
–
1/2 LT6231
V
S–
V
S+
–
+
1/2 LT6231
R7
499Ω
R4
499Ω
R2
196Ω
R1
10Ω
R3
196ΩR5
499Ω
623012 TA01a
A
V
= 40
BW = 5.1MHz
V
S
= ±1.5V to ±5V
I
S
= 10mA
E
N
= 5.8µV
RMS
INPUT REFERRED,
MEASUREMENT BW = 8MHz
V
S–
■
Ultrasound Amplifiers
■
Low Noise, Low Power Signal Processing
■
Active Filters
■
Driving A/D Converters
■
Rail-to-Rail Buffer Amplifiers
■
Low Noise Voltage: 1.1nV/√Hz
■
Low Supply Current: 3.5mA/Amp Max
■
Low Offset Voltage: 350µV Max
■
Gain Bandwidth Product:
LT6230: 215MHz; A
V
≥ 1
LT6230-10: 1450MHz; A
V
≥ 10
■
Wide Supply Range: 3V to 12.6V
■
Output Swings Rail-to-Rail
■
Common Mode Rejection Ratio 115dB Typ
■
Output Current: 30mA
■
Operating Temperature Range –40°C to 85°C
■
LT6230 Shutdown to 10µA Maximum
■
LT6230/LT6230-10 in SOT-23 Package
■
Dual LT6231 in 8-Pin SO and Tiny DFN Packages
■
LT6232 in 16-Pin SSOP Package
APPLICATIO S
U
FEATURES
TYPICAL APPLICATIO
U
DESCRIPTIO
U
215MHz, Rail-to-Rail Output,
1.1nV/√Hz, 3.5mA Op Amp Family
, LTC and LT are registered trademarks of Linear Technology Corporation.
The LT
®
6230/LT6231/LT6232 are single/dual/quad low
noise, rail-to-rail output unity gain stable op amps that
feature 1.1nV/√Hz noise voltage and draw only 3.5mA of
supply current per amplifier. These amplifiers combine
very low noise and supply current with a 215MHz gain
bandwidth product, a 70V/µs slew rate and are optimized
for low supply voltage signal conditioning systems. The
LT6230-10 is a single amplifier optimized for higher gain
applications resulting in higher gain bandwidth and slew
rate. The LT6230 and LT6230-10 include an enable pin
that can be used to reduce the supply current to less than
10µA.
The amplifier family has an output that swings within
50mV of either supply rail to maximize the signal dynamic
range in low supply applications and is specified on 3.3V,
5V and ±5V supplies. The e
n
• √I
SUPPLY
product of 1.9 per
amplifier is among the most noise efficient of any op amp.
The LT6230/LT6230-10 is available in the 6-lead SOT-23
package and the LT6231 dual is available in the 8-pin SO
package with standard pinouts. For compact layouts, the
dual is also available in a tiny dual fine pitch leadless
package (DFN). The LT6232 is available in the 16-pin
SSOP package.
LT6230/LT6230-10/
LT6231/LT6232
Noise Voltage and Unbalanced
Noise Current vs Frequency
Low Noise Low Power Instrumentation Amplifier
FREQUENCY (Hz)
NOISE VOLTAGE (nV/√Hz)
6
5
4
3
2
1
010 1k 10k 100k
623012 TA01b
100
V
S
= ±2.5V
T
A
= 25°C
V
CM
= 0V
NOISE VOLTAGE
NOISE CURRENT
UNBALANCED NOISE CURRENT (pA/√Hz)
6
5
4
3
2
1
0
LT6230/LT6230-10/
LT6231/LT6232
2
sn623012 623012fas
Total Supply Voltage (V
+
to V
–
) ............................ 12.6V
Input Current (Note 2) ........................................ ±40mA
Output Short-Circuit Duration (Note 3)............ Indefinite
Operating Temperature Range (Note 4) ...–40°C to 85°C
Specified Temperature Range (Note 5)....–40°C to 85°C
ABSOLUTE AXI U RATI GS
W
WW
U
PACKAGE/ORDER I FOR ATIO
UUW
(Note 1)
Junction Temperature...........................................150°C
Junction Temperature (DD Package) ................... 125°C
Storage Temperature Range ..................–65°C to 150°C
Storage Temperature Range
(DD Package) ...................................... –65°C to 125°C
Lead Temperature (Soldering, 10 sec).................. 300°C
T
JMAX
= 150°C, θ
JA
= 200°C/W 6231
6231I
LT6231CS8
LT6231IS8
*The temperature grade is identified by a label on the shipping container.Consult LTC Marketing for parts specified with wider operating temperature ranges.
ORDER PART
NUMBER
S6 PART
MARKING*
LTAFJ
LTAFK
LT6230CS6
LT6230IS6
LT6230CS6-10
LT6230IS6-10
ORDER PART
NUMBER
DD PART
MARKING*
LAEU
LT6231CDD
LT6231IDD
T
JMAX
= 125°C, θ
JA
= 160°C/W
UNDERSIDE METAL CONNECTED TO V
–
(PCB CONNECTION OPTIONAL)
T
JMAX
= 150°C, θ
JA
= 250°C/W
S8 PART
MARKING
ORDER PART
NUMBER
6232
6232I
LT6232CGN
LT6232IGN
GN PART
MARKING
ORDER PART
NUMBER
T
JMAX
= 150°C, θ
JA
= 135°C/W
TOP VIEW
DD PACKAGE
8-LEAD (3mm × 3mm) PLASTIC DFN
5
6
7
8
4
3
2
1OUT A
–IN A
+IN A
V
–
V
+
OUT B
–IN B
+IN B
+
–
+
–
6 V
+
5 ENABLE
4 –IN
OUT 1
TOP VIEW
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
V
–
2
+IN 3
TOP VIEW
V+
OUT B
–IN B
+IN B
OUT A
–IN A
+IN A
V–
S8 PACKAGE
8-LEAD PLASTIC SO
1
2
3
4
8
7
6
5
+
–
+
–
TOP VIEW
GN PACKAGE
16-LEAD NARROW PLASTIC SSOP
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
OUT A
–IN A
+IN A
V
+
+IN B
–IN B
OUT B
NC
OUT D
–IN D
+IN D
V
–
+IN C
–IN C
OUT C
NC
+
–
+
–
+
–
+
–
AD
BC
3
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply,
ENABLE = 0V, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230S6, LT6230S6-10 100 500 µV
LT6231S8, LT6232GN 50 350 µV
LT6231DD 75 450 µV
Input Offset Voltage Match 100 600 µV
(Channel-to-Channel) (Note 6)
I
B
Input Bias Current 510 µA
I
B
Match (Channel-to-Channel) (Note 6) 0.1 0.9 µA
I
OS
Input Offset Current 0.1 0.6 µA
Input Noise Voltage 0.1Hz to 10Hz 180 nV
P-P
e
n
Input Noise Voltage Density f = 10kHz, V
S
= 5V 1.1 1.7 nV/√Hz
i
n
Input Noise Current Density, Balanced Source f = 10kHz, V
S
= 5V, R
S
= 10k 1 pA/√Hz
Unbalanced Source f = 10kHz, V
S
= 5V, R
S
= 10k 2.4 pA/√Hz
Input Resistance Common Mode 6.5 MΩ
Differential Mode 7.5 kΩ
C
IN
Input Capacitance Common Mode 2.9 pF
Differential Mode 7.7 pF
A
VOL
Large-Signal Gain V
S
= 5V, V
O
= 0.5V to 4.5V, R
L
= 10k to V
S
/2 105 200 V/mV
R
L
= 1k to V
S
/2 21 40 V/mV
V
O
= 1V to 4V, R
L
= 100Ω to V
S
/2 5.4 9 V/mV
V
S
= 3.3V, V
O
= 0.65V to 2.65V, R
L
= 10k to V
S
/2 90 175 V/mV
R
L
= 1k to V
S
/2 16.5 32 V/mV
V
CM
Input Voltage Range Guaranteed by CMRR, V
S
= 5V, 0V 1.5 4 V
V
S
= 3.3V, 0V 1.15 2.65 V
CMRR Common Mode Rejection Ratio V
S
= 5V, V
CM
= 1.5V to 4V 90 115 dB
V
S
= 3.3V, V
CM
= 1.15V to 2.65V 90 115 dB
CMRR Match (Channel-to-Channel) (Note 6) V
S
= 5V, V
CM
= 1.5V to 4V 84 120 dB
PSRR Power Supply Rejection Ratio V
S
= 3V to 10V 90 115 dB
PSRR Match (Channel-to-Channel) (Note 6) V
S
= 3V to 10V 84 115 dB
Minimum Supply Voltage (Note 7) 3 V
V
OL
Output Voltage Swing LOW (Note 8) No Load 4 40 mV
I
SINK
= 5mA 85 190 mV
V
S
= 5V, I
SINK
= 20mA 240 460 mV
V
S
= 3.3V, I
SINK
= 15mA 185 350 mV
V
OH
Output Voltage Swing HIGH (Note 8) No Load 5 50 mV
I
SOURCE
= 5mA 90 200 mV
V
S
= 5V, I
SOURCE
= 20mA 325 600 mV
V
S
= 3.3V, I
SOURCE
= 15mA 250 400 mV
I
SC
Short-Circuit Current V
S
= 5V ±30 ±45 mA
V
S
= 3.3V ±25 ±40 mA
I
S
Supply Current per Amplifier 3.15 3.5 mA
Disabled Supply Current per Amplifier ENABLE = V
+
– 0.35V 0.2 10 µA
LT6230/LT6230-10/
LT6231/LT6232
4
sn623012 623012fas
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
ENABLE
ENABLE Pin Current ENABLE
= 0.3V –25 –75 µA
V
L
ENABLE Pin Input Voltage LOW 0.3 V
V
H
ENABLE Pin Input Voltage HIGH V
+
– 0.35V V
Output Leakage Current ENABLE
= V
+
– 0.35V, V
O
= 1.5V to 3.5V 0.2 10 µA
t
ON
Turn-On Time ENABLE
= 5V to 0V, R
L
= 1k, V
S
= 5V 300 ns
t
OFF
Turn-Off Time ENABLE
= 0V to 5V, R
L
= 1k, V
S
= 5V 41 µs
GBW Gain Bandwidth Product Frequency = 1MHz, V
S
= 5V 200 MHz
LT6230-10 1300 MHz
SR Slew Rate V
S
= 5V, A
V
= –1, R
L
= 1k, V
O
= 1.5V to 3.5V 42 60 V/µs
LT6230-10, V
S
= 5V, A
V
= –10, R
L
= 1k, 250 V/µs
V
O
= 1.5V to 3.5V
FPBW Full Power Bandwidth V
S
= 5V, V
OUT
= 3V
P-P
(Note 9) 4.8 6.3 MHz
LT6230-10, HD
2
= HD
3
= ≤ 1% 11 MHz
t
S
Settling Time (LT6230, LT6231, LT6232) 0.1%, V
S
= 5V, V
STEP
= 2V, A
V
= –1, R
L
= 1k 55 ns
TA = 25°C, VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply,
ENABLE = 0V, unless otherwise noted.
The ● denotes the specifications which apply over 0°C < TA < 70°C temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half
supply, ENABLE = 0V, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230S6, LT6230S6-10 ●600 µV
LT6231S8, LT6232GN ●450 µV
LT6231DD ●550 µV
Input Offset Voltage Match ●800 µV
(Channel-to-Channel) (Note 6)
V
OS
TC Input Offset Voltage Drift (Note 10) V
CM
= Half Supply ●0.5 3 µV/°C
I
B
Input Bias Current ●11 µA
I
B
Match (Channel-to-Channel) (Note 6) ●1µA
I
OS
Input Offset Current ●0.7 µA
A
VOL
Large-Signal Gain V
S
= 5V, V
O
= 0.5V to 4.5V, R
L
= 10k to V
S
/2 ●78 V/mV
R
L
= 1k to V
S
/2 ●17 V/mV
V
O
= 1V to 4V, R
L
= 100Ω to V
S
/2 ●4.1 V/mV
V
S
= 3.3V, V
O
= 0.65V to 2.65V, R
L
= 10k to V
S
/2 ●66 V/mV
R
L
= 1k to V
S
/2 ●13 V/mV
V
CM
Input Voltage Range Guaranteed by CMRR, V
S
= 5V, 0V ●1.5 4 V
V
S
= 3.3V, 0V ●1.15 2.65 V
CMRR Common Mode Rejection Ratio V
S
= 5V, V
CM
= 1.5V to 4V ●90 dB
V
S
= 3.3V, V
CM
= 1.15V to 2.65V ●85 dB
CMRR Match (Channel-to-Channel) (Note 6) V
S
= 5V, V
CM
= 1.5V to 4V ●84 dB
PSRR Power Supply Rejection Ratio V
S
= 3V to 10V ●85 dB
PSRR Match (Channel-to-Channel) (Note 6) V
S
= 3V to 10V ●79 dB
Minimum Supply Voltage (Note 7) ●3V
V
OL
Output Voltage Swing LOW (Note 8) No Load ●50 mV
I
SINK
= 5mA ●200 mV
V
S
= 5V, I
SINK
= 20mA ●500 mV
V
S
= 3.3V, I
SINK
= 15mA ●380 mV
ELECTRICAL CHARACTERISTICS
5
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
The ● denotes the specifications which apply over 0°C < TA < 70°C
temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, ENABLE = 0V, unless otherwise noted.
The ● denotes the specifications which apply over –40°C < TA < 85°C temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half
supply, ENABLE = 0V, unless otherwise noted. (Note 5)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230S6, LT6230S6-10 ●700 µV
LT6231S8, LT6232GN ●550 µV
LT6231DD ●650 µV
Input Offset Voltage Match ●1000 µV
(Channel-to-Channel) (Note 6)
V
OS
TC Input Offset Voltage Drift (Note 10) V
CM
= Half Supply ●0.5 3 µV/°C
I
B
Input Bias Current ●12 µA
I
B
Match (Channel-to-Channel) (Note 6) ●1.1 µA
I
OS
Input Offset Current ●0.8 µA
A
VOL
Large-Signal Gain V
S
= 5V, V
O
= 0.5V to 4.5V, R
L
= 10k to V
S
/2 ●72 V/mV
R
L
= 1k to V
S
/2 ●16 V/mV
V
O
= 1V to 4V, R
L
= 100Ω to V
S
/2 ●3.6 V/mV
V
S
= 3.3V, V
O
= 0.65V to 2.65V,R
L
= 10k to V
S
/2 ●60 V/mV
R
L
= 1k to V
S
/2 ●12 V/mV
V
CM
Input Voltage Range Guaranteed by CMRR, V
S
= 5V, 0V ●1.5 4 V
V
S
= 3.3V, 0V ●1.15 2.65 V
CMRR Common Mode Rejection Ratio V
S
= 5V, V
CM
= 1.5V to 4V ●90 dB
V
S
= 3.3V, V
CM
= 1.15V to 2.65V ●85 dB
CMRR Match (Channel-to-Channel) (Note 6) V
S
= 5V, V
CM
= 1.5V to 4V ●84 dB
PSRR Power Supply Rejection Ratio V
S
= 3V to 10V ●85 dB
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OH
Output Voltage Swing HIGH (Note 8) No Load ●60 mV
I
SOURCE
= 5mA ●215 mV
V
S
= 5V, I
SOURCE
= 20mA ●650 mV
V
S
= 3.3V, I
SOURCE
= 15mA ●430 mV
I
SC
Short-Circuit Current V
S
= 5V ●±25 mA
V
S
= 3.3V ●±20 mA
I
S
Supply Current per Amplifier ●4.2 mA
Disabled Supply Current per Amplifier ENABLE = V
+
– 0.25V ●1µA
I
ENABLE
ENABLE Pin Current ENABLE = 0.3V ●–85 µA
V
L
ENABLE Pin Input Voltage LOW ●0.3 V
V
H
ENABLE Pin Input Voltage HIGH ● V
+
– 0.25V V
Output Leakage Current ENABLE = V
+
– 0.25V, V
O
= 1.5V to 3.5V ●1µA
t
ON
Turn-On Time ENABLE = 5V to 0V, R
L
= 1k, V
S
= 5V ●300 ns
t
OFF
Turn-Off Time ENABLE = 0V to 5V, R
L
= 1k, V
S
= 5V ●65 µs
SR Slew Rate V
S
= 5V, A
V
= –1, R
L
= 1k, V
O
= 1.5V to 3.5V ●35 V/µs
LT6230-10, A
V
= –10, R
L
= 1k, ●225 V/µs
V
O
= 1.5V to 3.5V
FPBW Full Power Bandwidth (Note 9) V
S
= 5V, V
OUT
= 3V
P-P
●3.7 MHz
LT6230, LT6231, LT6232
ELECTRICAL CHARACTERISTICS
LT6230/LT6230-10/
LT6231/LT6232
6
sn623012 623012fas
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230, LT6230-10 100 500 µV
LT6231S8, LT6232GN 50 350 µV
LT6231DD 75 450 µV
Input Offset Voltage Match 100 600 µV
(Channel-to-Channel) (Note 6)
I
B
Input Bias Current 510 µA
I
B
Match (Channel-to-Channel) (Note 6) 0.1 0.9 µA
I
OS
Input Offset Current 0.1 0.6 µA
Input Noise Voltage 0.1Hz to 10Hz 180 nV
P-P
e
n
Input Noise Voltage Density f = 10kHz 1.1 1.7 nV/√Hz
i
n
Input Noise Current Density, Balanced Source f = 10kHz, R
S
= 10k 1 pA/√Hz
Unbalanced Source f = 10kHz, R
S
= 10k 2.4 pA/√Hz
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
PSRR Match (Channel-to-Channel) (Note 6) V
S
= 3V to 10V ●79 dB
Minimum Supply Voltage (Note 7) ●3V
V
OL
Output Voltage Swing LOW (Note 8) No Load ●60 mV
I
SINK
= 5mA ●210 mV
V
S
= 5V, I
SINK
= 15mA ●510 mV
V
S
= 3.3V, I
SINK
= 15mA ●390 mV
V
OH
Output Voltage Swing HIGH (Note 6) No Load ●70 mV
I
SOURCE
= 5mA ●220 mV
V
S
= 5V, I
SOURCE
= 20mA ●675 mV
V
S
= 3.3V, I
SOURCE
= 15mA ●440 mV
I
SC
Short-Circuit Current V
S
= 5V ●±15 mA
V
S
= 3.3V ●±15 mA
I
S
Supply Current per Amplifier ●4.4 mA
Disabled Supply Current per Amplifier ENABLE = V
+
– 0.2V ●1µA
I
ENABLE
ENABLE Pin Current ENABLE = 0.3V ●–100 µA
V
L
ENABLE Pin Input Voltage LOW ●0.3 V
V
H
ENABLE Pin Input Voltage HIGH ● V
+
– 0.2V V
Output Leakage Current ENABLE = V
+
– 0.2V, V
O
= 1.5V to 3.5V ●1µA
t
ON
Turn-On Time ENABLE = 5V to 0V, R
L
= 1k, V
S
= 5V ●300 ns
t
OFF
Turn-Off Time ENABLE = 0V to 5V, R
L
= 1k, V
S
= 5V ●72 µs
SR Slew Rate V
S
= 5V, A
V
= –1, R
L
= 1k, V
O
= 1.5V to 3.5V ●31 V/µs
LT6230-10, A
V
= –10, R
L
= 1k, ●185 V/µs
V
O
= 1.5V to 3.5V
FPBW Full Power Bandwidth (Note 9) V
S
= 5V, V
OUT
= 3V
P-P
●3.3 MHz
LT6230, LT6231, LT6232
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over –40°C < TA < 85°C
temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, ENABLE = 0V, unless otherwise noted. (Note 5)
TA = 25°C, VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted.
7
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Resistance Common Mode 6.5 MΩ
Differential Mode 7.5 kΩ
C
IN
Input Capacitance Common Mode 2.4 pF
Differential Mode 6.5 pF
A
VOL
Large-Signal Gain V
O
= ±4.5V, R
L
= 10k 140 260 V/mV
R
L
= 1k 35 65 V/mV
V
O
= ±2V, R
L
= 100Ω8.5 16 V/mV
V
CM
Input Voltage Range Guaranteed by CMRR –3 4 V
CMRR Common Mode Rejection Ratio V
CM
= –3V to 4V 95 120 dB
CMRR Match (Channel-to-Channel) (Note 6) V
CM
= –3V to 4V 89 125 dB
PSRR Power Supply Rejection Ratio V
S
= ±1.5V to ±5V 90 115 dB
PSRR Match (Channel-to-Channel) (Note 6) V
S
= ±1.5V to ±5V 84 115 dB
V
OL
Output Voltage Swing LOW (Note 8) No Load 4 40 mV
I
SINK
= 5mA 85 190 mV
I
SINK
= 20mA 240 460 mV
V
OH
Output Voltage Swing HIGH (Note 8) No Load 5 50 mV
I
SOURCE
= 5mA 90 200 mV
I
SOURCE
= 20mA 325 600 mV
I
SC
Short-Circuit Current ±30 mA
I
S
Supply Current per Amplifier 3.3 3.9 mA
Disabled Supply Current per Amplifier ENABLE = 4.65V 0.2 µA
I
ENABLE
ENABLE Pin Current ENABLE = 0.3V –35 –85 µA
V
L
ENABLE Pin Input Voltage LOW 0.3 V
V
H
ENABLE Pin Input Voltage HIGH 4.65 V
Output Leakage Current ENABLE = V
+
– 4.65V, V
O
= ±1V 0.2 10 µA
t
ON
Turn-On Time ENABLE = 5V to 0V, R
L
= 1k 300 ns
t
OFF
Turn-Off Time ENABLE = 0V to 5V, R
L
= 1k 62 µs
GBW Gain Bandwidth Product Frequency = 1MHz 150 215 MHz
LT6230-10 1000 1450 MHz
SR Slew Rate A
V
= –1, R
L
= 1k, V
O
= –2V to 2V 50 70 V/µs
LT6230-10, A
V
= –10, R
L
= 1k, V
O
= –2V to 2V 320 V/µs
FPBW Full Power Bandwidth V
OUT
= 3V
P-P
(Note 9) 5.3 7.4 MHz
LT6230-10, HD2 = HD3 ≤ 1% 11 MHz
t
S
Settling Time (LT6230, LT6231, LT6232) 0.1%, V
STEP
= 2V, A
V
= –1, R
L
= 1k 50 ns
TA = 25°C, VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
LT6230/LT6230-10/
LT6231/LT6232
8
sn623012 623012fas
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230S6, LT6230S6-10 ●600 µV
LT6231S8, LT6232GN ●450 µV
LT6231DD ●550 µV
Input Offset Voltage Match ●800 µV
(Channel-to-Channel) (Note 6)
V
OS
TC Input Offset Voltage Drift (Note 10) ●0.5 3 µV/°C
I
B
Input Bias Current ●11 µA
I
B
Match (Channel-to-Channel) (Note 6) ●1µA
I
OS
Input Offset Current ●0.7 µA
A
VOL
Large-Signal Gain V
O
= ±4.5V, R
L
= 10k ●100 V/mV
R
L
= 1k ●27 V/mV
V
O
= ±2V, R
L
= 100Ω●6V/mV
V
CM
Input Voltage Range Guaranteed by CMRR ●–3 4 V
CMRR Common Mode Rejection Ratio V
CM
= –3V to 4V ●95 dB
CMRR Match (Channel-to-Channel) (Note 6) V
CM
= –3V to 4V ●89 dB
PSRR Power Supply Rejection Ratio V
S
= ±1.5V to ±5V ●85 dB
PSRR Match (Channel-to-Channel) (Note 6) V
S
= ±1.5V to ±5V ●79 dB
V
OL
Output Voltage Swing LOW (Note 8) No Load ●50 mV
I
SINK
= 5mA ●200 mV
I
SINK
= 20mA ●500 mV
V
OH
Output Voltage Swing HIGH (Note 8) No Load ●60 mV
I
SOURCE
= 5mA ●215 mV
I
SOURCE
= 20mA ●650 mV
I
SC
Short-Circuit Current ●±25 mA
I
S
Supply Current per Amplifier ●4.6 mA
Disabled Supply Current per Amplifier ENABLE = 4.75V ●1µA
I
ENABLE
ENABLE Pin Current ENABLE = 0.3V ●–95 µA
V
L
ENABLE Pin Input Voltage LOW ●0.3 V
V
H
ENABLE Pin Input Voltage HIGH ●4.75 V
Output Leakage Current ENABLE = 4.75V, V
O
= ±1V ●1µA
t
ON
Turn-On Time ENABLE = 5V to 0V, R
L
= 1k ●300 ns
t
OFF
Turn-Off Time ENABLE = 0V to 5V, R
L
= 1k ●85 µs
SR Slew Rate A
V
= –1, R
L
= 1k, V
O
= –2V to 2V ●44 V/µs
LT6230-10, A
V
= –10, R
L
= 1k, V
O
= –2V to 2V ●315 V/µs
FPBW Full Power Bandwidth V
OUT
= 3V
P-P
(Note 9) ●4.66 MHz
LT6230, LT6231, LT6232
The ● denotes the specifications which apply over 0°C < TA < 70°C
temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
9
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
OS
Input Offset Voltage LT6230, LT6230-10 ●700 µV
LT6231S8, LT6232GN ●550 µV
LT6231DD ●650 µV
Input Offset Voltage Match ●1000 µV
(Channel-to-Channel) (Note 6)
V
OS
TC Input Offset Voltage Drift (Note 10) ●0.5 3 µV/°C
I
B
Input Bias Current ●12 µA
I
B
Match (Channel-to-Channel) (Note 6) ●1.1 µA
I
OS
Input Offset Current ●0.8 µA
A
VOL
Large-Signal Gain V
O
= ±4.5V, R
L
= 10k ●93 V/mV
R
L
= 1k ●25 V/mV
V
O
= ±1.5V, R
L
= 100Ω●4.8 V/mV
V
CM
Input Voltage Range Guaranteed by CMRR ●–3 4 V
CMRR Common Mode Rejection Ratio V
CM
= –3V to 4V ●95 dB
CMRR Match (Channel-to-Channel) (Note 6) V
CM
= –3V to 4V ●89 dB
PSRR Power Supply Rejection Ratio V
S
= ±1.5V to ±5V ●85 dB
PSRR Match (Channel-to-Channel) (Note 6) V
S
= ±1.5V to ±5V ●79 dB
V
OL
Output Voltage Swing LOW (Note 8) No Load ●60 mV
I
SINK
= 5mA ●210 mV
I
SINK
= 15mA ●510 mV
V
OH
Output Voltage Swing HIGH (Note 8) No Load ●70 mV
I
SOURCE
= 5mA ●220 mV
I
SOURCE
= 20mA ●675 mV
I
SC
Short-Circuit Current ●±15 mA
I
S
Supply Current per Amplifier ●4.85 mA
Disabled Supply Current per Amplifier ENABLE = 4.8V ●1µA
I
ENABLE
ENABLE Pin Current ENABLE = 0.3V ●–110 µA
V
L
ENABLE Pin Input Voltage LOW ●0.3 V
V
H
ENABLE Pin Input Voltage HIGH ●4.8 V
Output Leakage Current ENABLE = 4.8V, V
O
= ±1V ●1µA
t
ON
Turn-On Time ENABLE = 5V to 0V, R
L
= 1k ●300 ns
t
OFF
Turn-Off Time ENABLE = 0V to 5V, R
L
= 1k ●72 µs
SR Slew Rate A
V
= –1, R
L
= 1k, V
O
= –2V to 2V ●37 V/µs
LT6230-10, A
V
= –10, R
L
= 1k, V
O
= –2V to 2V ●260 V/µs
FPBW Full Power Bandwidth (Note 9) V
OUT
= 3V
P-P
●3.9 MHz
LT6230, LT6231, LT6232
The ● denotes the specifications which apply over –40°C < TA < 85°C
temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. (Note 5)
ELECTRICAL CHARACTERISTICS
LT6230/LT6230-10/
LT6231/LT6232
10
sn623012 623012fas
Note 1: Absolute maximum ratings are those values beyond which the life
of the device may be impaired.
Note 2: Inputs are protected by back-to-back diodes. If the differential
input voltage exceeds 0.7V, the input current must be limited to less than
40mA.
Note 3: A heat sink may be required to keep the junction temperature
below the absolute maximum rating when the output is shorted
indefinitely.
Note 4: The LT6230C/LT6230I the LT6231C/LT6231I, and LT6232C/
LT6232I are guaranteed functional over the temperature range of –40°C
and 85°C.
Note 5: The LT6230C/LT6231C/LT6232C are guaranteed to meet specified
performance from 0°C to 70°C. The LT6230C/LT6231C/LT6232C are
designed, characterized and expected to meet specified performance from
–40°C to 85°C, but are not tested or QA sampled at these temperatures.
The LT6230I/LT6231I/LT6232I are guaranteed to meet specified
performance from –40°C to 85°C.
Note 6: Matching parameters are the difference between the two amplifiers
A and D and between B and C of the LT6232; between the two amplifiers
of the LT6231. CMRR and PSRR match are defined as follows: CMRR and
PSRR are measured in µV/V on the matched amplifiers. The difference is
calculated between the matching sides in µV/V. The result is converted
to dB.
Note 7: Minimum supply voltage is guaranteed by power supply rejection
ratio test.
Note 8: Output voltage swings are measured between the output and
power supply rails.
Note 9: Full-power bandwidth is calculated from the slew rate:
FPBW = SR/2πV
P
Note 10: This parameter is not 100% tested.
ELECTRICAL CHARACTERISTICS
TEMPERATURE (°C)
–50
INPUT BIAS CURRENT (µA)
25
623012 GO5
–25 0 50
10
9
8
7
6
5
4
375 100 125
V
CM
= 4V
V
CM
= 1.5V
V
S
= 5V, 0V
TYPICAL PERFOR A CE CHARACTERISTICS
UW
VOS Distribution Supply Current vs Supply Voltage
(Per Amplifier) Offset Voltage vs Input Common
Mode Voltage
Input Bias Current vs
Common Mode Voltage Input Bias Current vs Temperature Output Saturation Voltage vs
Load Current (Output Low)
(LT6230/LT6231/LT6232)
INPUT OFFSET VOLTAGE (µV)
–200
0
NUMBER OF UNITS
10
20
30
40
–100 0 100 200
623012 GO1
50
100
90
80
70
60
–150 –50 50 150
V
S
= 5V, 0V
V
CM
= V
+
/2
S8
TOTAL SUPPLY VOLTAGE (V)
0
SUPPLY CURRENT (mA)
6
623012 GO2
24 8
6
5
4
3
2
1
010 12 14
T
A
= 125°C
T
A
= 25°C
T
A
= –55°C
INPUT COMMON MODE VOLTAGE (V)
0
OFFSET VOLTAGE (mV)
1.5
623012 GO3
0.5 1 2
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0 3452.5 3.5 4.5
T
A
= –55°C
V
S
= 5V, 0V
T
A
= 25°C
T
A
= 125°C
COMMON MODE VOLTAGE (V)
–1
INPUT BIAS CURRENT (µA)
2
623012 GO4
01 3
14
12
10
8
6
4
2
–2
0
456
T
A
= 125°C
T
A
= –55°C
T
A
= 25°C
V
S
= 5V, 0V
LOAD CURRENT (mA)
0.01 0.1
0.001
OUTPUT SATURATION VOLTAGE (V)
0.01
10
1 10010
623012 GO6
0.1
1
V
S
= 5V, 0V
T
A
= –55°C
T
A
= 125°C
T
A
= 25°C
11
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Output Saturation Voltage vs
Load Current (Output High) Minimum Supply Voltage Output Short Circuit Current vs
Power Supply Voltage
LOAD CURRENT (mA)
OUTPUT SATURATION VOLTAGE (V)
623012 G07
0.01 0.1
0.01
10
1 10010
0.001
0.1
1
V
S
= 5V, 0V
T
A
= –55°C
T
A
= 125°C
T
A
= 25°C
TOTAL SUPPLY VOLTAGE (V)
0
OFFSET VOLTAGE (mV)
1.5
623012 G08
0.5 1 2
1.0
0.8
0.6
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0 3452.5 3.5 4.5
T
A
= –55°C
T
A
= 125°C
T
A
= 25°C
V
CM
= V
S
/2
POWER SUPPLY VOLTAGE (±V)
1.5
OUTPUT SHORT-CIRCUIT CURRENT (mA)
3
623012 GO9
2 2.5 3.5
70
60
40
20
50
30
10
0
–20
–40
–70
–60
–10
–30
–50
4 4.5 5
T
A
= 125°C
T
A
= –55°C
T
A
= –55°C
T
A
= 25°C
SINKING
SOURCING
T
A
= 25°C
T
A
= 125°C
Open Loop Gain Open Loop Gain Open Loop Gain
Offset Voltage vs Output Current Warm-Up Drift vs Time Total Noise vs Total Source
Resistance
OUTPUT VOLTAGE (V)
0
INPUT VOLTAGE (mV)
1.5
623012 G10
0.5 1 2
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5 32.5
R
L
= 100Ω
R
L
= 1k
V
S
= 3V, 0V
T
A
= 25°C
OUTPUT VOLTAGE (V)
0
INPUT VOLTAGE (mV)
1.5
623012 G11
0.5 1 2
0
3452.5 3.5 4.5
R
L
= 100Ω
R
L
= 1k
V
S
= 5V, 0V
T
A
= 25°C
2.5
2.0
1.5
1.0
0.5
–0.5
–1.0
–1.5
–2.0
–2.5
OUTPUT VOLTAGE (V)
–5
INPUT VOLTAGE (mV)
–2
623012 G12
–4 –3 –1
0
135024
R
L
= 100Ω
R
L
= 1k
V
S
= ±5V
T
A
= 25°C
2.5
2.0
1.5
1.0
0.5
–0.5
–1.0
–1.5
–2.0
–2.5
OUTPUT CURRENT (mA)
–75
OFFSET VOLTAGE (mV)
623012 G13
–45 –15
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0 030 7560–60 –30 15 45
T
A
= –55°C
T
A
= 125°C
V
S
= ±5V
T
A
= 25°C
TIME AFTER POWER-UP (s)
0
CHANGE IN OFFSET VOLTAGE (µV)
60
623012 G14
20 100
30
28
24
20
16
26
22
18
14
12
10 140
40 80 120 160
T
A
= 25°C
V
S
= ±5V
V
S
= ±2.5V
V
S
= ±1.5V
SOURCE RESISTANCE (Ω)
1
TOTAL NOISE (nV/√Hz)
10
10 1k 10k 100k
623012 G15
0.1 100
100 V
S
= ±2.5V
V
CM
= 0V
f = 100kHz
UNBALANCED
SOURCE
RESISTORS
TOTAL NOISE
RESISTOR NOISE
AMPLIFIER NOISE VOLTAGE
(LT6230/LT6231/LT6232)
LT6230/LT6230-10/
LT6231/LT6232
12
sn623012 623012fas
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Noise Voltage and Unbalanced
Noise Current vs Frequency
0.1Hz to 10Hz Output Voltage
Noise Gain Bandwidth and Phase Margin
vs Temperature
Open Loop Gain vs Frequency Gain Bandwidth and Phase Margin
vs Supply Voltage Slew Rate vs Temperature
Output Impedance vs Frequency Common Mode Rejection Ratio vs
Frequency Channel Separation vs Frequency
FREQUENCY (Hz)
NOISE VOLTAGE (nV/√Hz)
6
5
4
3
2
1
010 1k 10k 100k
623012 G16
100
V
S
= ±2.5V
T
A
= 25°C
V
CM
= 0V
NOISE VOLTAGE
NOISE CURRENT
UNBALANCED NOISE CURRENT (pA/√Hz)
6
5
4
3
2
1
0
TEMPERATURE (°C)
–55
GAIN BANDWIDTH (MHz)
5
623012 G18
–25 35
240
220
200
180
140
160
PHASE MARGIN (DEG)
70
60
50
40
65 95 125
V
S
= ±5V
V
S
= 3V, 0V
V
S
= ±5V
V
S
= 3V, 0V
PHASE MARGIN
GAIN BANDWIDTH
C
L
= 5pF
R
L
= 1k
V
CM
= V
S
/2
FREQUENCY (Hz)
GAIN (dB)
80
70
50
30
0
–10
60
40
10
20
–20
PHASE (dB)
120
100
60
20
–60
80
40
–20
–40
0
–80
100k 10M 100M 1G
623012 G19
1M
CL = 5pF
RL = 1k
VCM = VS/2
PHASE
GAIN
VS = ±5V
VS = 3V, 0V
VS = ±5V
VS = 3V, 0V
TOTAL SUPPLY VOLTAGE (V)
0
GAIN BANDWIDTH (MHz)
6
623012 G20
24 8
220
240
200
180
140
160
PHASE MARGIN (DEG)
70
60
50
40
10 12 14
PHASE MARGIN
GAIN BANDWIDTH
T
A
= 25°C
C
L
= 5pF
R
L
= 1k
TEMPERATURE (°C)
–55
SLEW RATE (V/µs)
5
623012 G21
–35 –15 45
90
100
110
120
80
70
50
20
30
60
40
8525 65 105 125
V
S
= ±5V FALLING
V
S
= ±2.5V RISING
A
V
= –1
R
F
= R
G
= 1k
V
S
= ±5V RISING
V
S
= ±2.5V FALLING
FREQUENCY (Hz)
1
OUTPUT IMPEDANCE (Ω)
10
100k 10M 100M
623012 G22
0.01
0.1
1M
1k
100
VS = 5V, 0V
AV = 10
AV = 1 AV = 2
FREQUENCY (Hz)
20
COMMON MODE REJECTION RATIO (dB)
40
60
80
120
100
10k 100M100k 1G10M
623012 G23
01M
V
S
= 5V, 0V
V
CM
= V
S
/2
FREQUENCY (Hz)
100k
CHANNEL SEPARATION (dB)
–40
–50
–60
–70
–80
–90
–100
–110
–120
–130
–140 1M 10M 100M
623012 G24
A
V
= 1
T
A
= 25°C
V
S
= ±5V
5s/DIV
623012 G17
100nV
100nV/DIV
–100nV
V
S
= ±2.5V
(LT6230/LT6231/LT6232)
13
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Power Supply Rejection Ratio vs
Frequency Series Output Resistance and
Overshoot vs Capacitive Load Series Output Resistance and
Overshoot vs Capacitive Load
FREQUENCY (Hz)
20
POWER SUPPLY REJECTION RATIO (dB)
40
60
80
120
100
1k 10k 100M100k 10M
623012 G25
01M
V
S
= 5V, 0V
T
A
= 25°C
V
CM
= V
S
/2
NEGATIVE SUPPLY
POSITIVE SUPPLY
OUTPUT STEP (V)
–4
SETTLING TIME (ns)
0
623012 G28
–3 –2 –1 1
100
200
150
50
0234
1mV
10mV
1mV
10mV
V
S
= ±5V
T
A
= 25°C
A
V
= 1
+
–
500Ω
V
OUT
V
IN
Settling Time vs Output Step
(Non-Inverting) Settling Time vs Output Step
(Inverting) Maximum Undistorted Output
Signal vs Frequency
Distortion vs Frequency Distortion vs Frequency Distortion vs Frequency
OUTPUT STEP (V)
–4
SETTLING TIME (ns)
0
623012 G29
–3 –2 –1 1
200
150
0
50
100
234
1mV
10mV
1mV
10mV
V
S
= ±5V
T
A
= 25°C
A
V
= –1
+
–
500Ω
500Ω
V
OUT
V
IN
CAPACITIVE LOAD (pF)
10
OVERSHOOT (%)
50
45
40
35
30
25
20
15
10
5
0100 1000
623012 G26
V
S
= 5V, 0V
A
V
= 1
R
S
= 10Ω
R
S
= 20Ω
R
S
= 50Ω
R
L
= 50Ω
CAPACITIVE LOAD (pF)
10
OVERSHOOT (%)
50
45
40
35
30
25
20
15
10
5
0100 1000
623012 G27
V
S
= 5V, 0V
A
V
= 2 R
S
= 10Ω
R
S
= 20Ω
R
S
= 50Ω
R
L
= 50Ω
FREQUENCY (Hz)
10k
OUTPUT VOLTAGE SWING (V
P–P
)
10
9
8
7
6
5
4
3
2100k 1M 10M
623012 G30
V
S
= ±5V
T
A
= 25°C
HD
2
, HD
3
< –40dBc
A
V
= –1
A
V
= 2
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G31
V
S
= ±2.5V
A
V
= 1
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 1k, 3RD
R
L
= 100Ω, 2ND
R
L
= 1k, 2ND
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G32
V
S
= ±5V
A
V
= 1
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 1k, 3RD
R
L
= 1k, 2ND
R
L
= 100Ω, 2ND
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G33
V
S
= ±2.5V
A
V
= 2
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 1k, 3RD
R
L
= 1k, 2ND
R
L
= 100Ω, 2ND
(LT6230/LT6231/LT6232)
LT6230/LT6230-10/
LT6231/LT6232
14
sn623012 623012fas
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Large Signal Response Small Signal Response
Distortion vs Frequency
Large Signal Response Output Overdrive Recovery
Supply Current vs ENABLE Pin
Voltage ENABLE Pin Current vs ENABLE
Pin Voltage ENABLE Pin Response Time
PIN VOLTAGE (V)
SUPPLY CURRENT (mA)
–1.0
623012 G39
–2.0 0
4.5
4.0
3.5
3.0
2.5
2.0
1.0
0.5
1.5
01.0 2.0
V
S
= ±2.5V
T
A
= 125°C
T
A
= 25°C
T
A
= –55°C
PIN VOLTAGE (V)
ENABLE PIN CURRENT (µA)
623012 G40
30
25
20
15
10
5
0
T
A
= 125°C
V
S
= ±2.5V
A
V
= 1
T
A
= 25°C
T
A
= –55°C
–1.0
–2.0 0 1.0 2.0
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G34
V
S
= ±5V
A
V
= 2
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 1k, 2ND
R
L
= 100Ω, 2ND
R
L
= 1k, 3RD
(LT6230/LT6231/LT6232)
V
S
= ±2.5V 100µs/DIV
V
IN
= 0.5V
A
V
= 1
R
L
= 1k 623345 G41
0.5V
5V
0V
0V
V
OUT
ENABLE PIN
V
IN
(1V/DIV)
V
S
= ±2.5V 200ns/DIV
A
V
= 3
623345 G38
0V
0V
V
OUT
(2V/DIV)
2V/DIV
V
S
= ±5V 200ns/DIV
A
V
= 1
R
L
= 1k 623345 G37
0V
–5V
5V
50mV/DIV
V
S
= ±2.5V 200ns/DIV
A
V
= 1
R
L
= 1k 623345 G36
0V
1V/DIV
V
S
= ±2.5V 200ns/DIV
A
V
= –1
R
L
= 1k 623345 G35
–2V
2V
0V
(LT6230) ENABLE Characteristics
15
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
TEMPERATURE (°C)
–55
SLEW RATE (V/µs)
5
623012 G43
–35 –15 45
450
500
550
600
400
350
250
100
150
300
200
8525 65 105 125
V
S
= ±5V FALLING
V
S
= ±2.5V RISING
A
V
= –10
R
F
= 1k
R
G
= 100Ω
V
S
= ±5V RISING
V
S
= ±2.5V FALLING
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Gain Bandwidth and Phase Margin
vs Temperature Slew Rate vs Temperature Series Output Resistor and
Overshoot vs Capacitive Load
Open Loop Gain and Phase vs
Frequency Gain Bandwidth and Phase Margin
vs Supply Voltage Gain Bandwidth vs Resistor Load
Common Mode Rejection Ratio vs
Frequency Maximum Undistorted Output
Signal vs Frequency 2nd and 3rd Harmonic Distortion vs
Frequency
TEMPERATURE (°C)
–50
GAIN BANDWIDTH (MHz)
25
623012 G42
–25 0 50
1700
1500
1300
1100
900
PHASE MARGIN (DEG)
70
80
60
50
40
75 100 125
V
S
= ±5V
V
S
= 3V, 0V
V
S
= ±5V
V
S
= 3V, 0V
PHASE MARGIN
GAIN BANDWIDTH
A
V
= 10
FREQUENCY (Hz)
GAIN (dB)
90
80
70
60
50
40
30
20
10
0
–10
PHASE (DEG)
120
100
80
60
40
20
0
–20
–40
–60
–80
100k 10M 100M 1G
623012 G45
1M
A
V
= 10
C
L
= 5pF
R
L
= 1k
V
CM
= V
S
/2
V
S
= 3V, 0V
V
S
= ±5V
PHASE
GAIN
V
S
= ±5V
V
S
= 3V, 0V
TOTAL SUPPLY VOLTAGE (V)
0
GAIN BANDWIDTH (MHz)
6
623012 G46
24 8
1700
1450
1200
950
PHASE MARGIN (DEG)
100
50
0
10 12
PHASE MARGIN
GAIN BANDWIDTH
T
A
= 25°C
A
V
= 10
C
L
= 5pF
R
L
= 1k
TOTAL RESISTOR LOAD (Ω)
(INCLUDES FEEDBACK R)
0
GAIN BANDWIDTH (MHz)
600
623012 G47
200 400 800
1600
1400
1200
800
600
400
200
0
1000
1000
A
V
= 10
V
S
= ±5V
T
A
= 25°C
R
F
= 1k
R
G
= 100
FREQUENCY (Hz)
20
COMMON MODE REJECTION RATIO (dB)
40
60
80
120
100
10k 1G100M100k 10M
623012 G48
01M
V
S
= 5V, 0V
V
CM
= V
S
/2
FREQUENCY (Hz)
10k
OUTPUT VOLTAGE SWING (VP–P)
10
9
8
7
6
5
4
3
2
1
0100k 1M 100M10M
623012 G49
VS = ±5V
TA = 25°C
AV = 10
HD2 = HD3 ≤ 40dBc
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G50
V
S
= ±2.5V
A
V
= 10
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 100Ω, 2ND
R
L
= 1k, 3RD
R
L
= 1k, 2ND
CAPACITIVE LOAD (pF)
10
OVERSHOOT (%)
70
60
50
40
30
20
10
0100 1000 10000
623012 G44
V
S
= 5V, 0V
A
V
= 10
R
S
= 10Ω
R
S
= 20Ω
R
S
= 50Ω
(LT6230-10)
LT6230/LT6230-10/
LT6231/LT6232
16
sn623012 623012fas
TYPICAL PERFOR A CE CHARACTERISTICS
UW
2nd and 3rd Harmonic Distortion vs
Frequency Large Signal Response Output-Overload Recovery
Small Signal Response Input Referred High Frequency
Noise Spectrum
V
S
= ±5V 100ns/DIV
A
V
= 10
R
F
= 900Ω, R
G
= 100Ω623345 G52
0V
V
OUT
(2V/DIV)
V
S
= 5V, 0V 100ns/DIV
A
V
= 10
R
F
= 900Ω, R
G
= 100Ω623345 G53
0V
V
OUT
(2V/DIV)
0V
V
IN
(0.5V/DIV)
V
S
= 5V, 0V 100ns/DIV
A
V
= 10
R
F
= 900Ω, R
G
= 100Ω623345 G54
2.5V
V
OUT
(100mV/DIV)
FREQUENCY (Hz)
10k
DISTORTION (dBc)
–40
–50
–60
–70
–80
–90
–100 100k 1M 10M
623012 G51
V
S
= ±5V
A
V
= 10
V
OUT
= 2V
(P–P)
R
L
= 100Ω, 3RD
R
L
= 100Ω, 2ND
R
L
= 1k, 2ND
R
L
= 1k, 3RD
(LT6230-10)
100kHz 50MHz
5MHz/DIV
623345 G55
1nV/√Hz/DIV
10
0
17
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
Input Protection
There are back-to-back diodes, D1 and D2 across the + and
– inputs of these amplifiers to limit the differential input
voltage to ±0.7V. The inputs of the LT6230/LT6231/
LT6232 do not have internal resistors in series with the
input transistors. This technique is often used to protect
the input devices from over voltage that causes excessive
current to flow. The addition of these resistors would
significantly degrade the low noise voltage of these ampli-
fiers. For instance, a 100Ω resistor in series with each
input would generate 1.8nV/√Hz of noise, and the total
amplifier noise voltage would rise from 1.1nV/√Hz to
2.1nV/√Hz. Once the input differential voltage exceeds
±0.7V, steady state current conducted through the protec-
tion diodes should be limited to ±40mA. This implies 25Ω
of protection resistance is necessary per volt of overdrive
beyond ±0.7V. These input diodes are rugged enough to
APPLICATIO S I FOR ATIO
WUUU
Amplifier Characteristics
Figure 1 is a simplified schematic of the LT6230/LT6231/
LT6232, which has a pair of low noise input transistors Q1
and Q2. A simple current mirror Q3/Q4 converts the
differential signal to a single-ended output, and these
transistors are degenerated to reduce their contribution to
the overall noise.
Capacitor C1 reduces the unity cross frequency and
improves the frequency stability without degrading the
gain bandwidth of the amplifier. Capacitor C
M
sets the
overall amplifier gain bandwidth. The differential drive
generator supplies current to transistors Q5 and Q6 that
swing the output from rail-to-rail.
handle transient currents due to amplifier slew rate over-
drive and clipping without protection resistors.
The photo of Figure 2 shows the output response to an
input overdrive with the amplifier connected as a voltage
follower. With the input signal low, current source I
1
saturates and the differential drive generator drives Q6
into saturation so the output voltage swings all the way to
V
–
. The input can swing positive until transistor Q2 satu-
rates into current mirror Q3/Q4. When saturation occurs,
the output tries to phase invert, but diode D2 conducts
current from the signal source to the output through the
feedback connection. The output is clamped a diode drop
below the input. In this photo, the input signal generator
is limiting at about 20mA.
With the amplifier connected in a gain of A
V
≥ 2, the output
can invert with very heavy overdrive. To avoid this inver-
sion, limit the input overdrive to 0.5V beyond the power
supply rails.
ESD
The LT6230/LT6231/LT6232 have reverse-biased ESD
protection diodes on all inputs and outputs as shown in
Figure 1. If these pins are forced beyond either supply,
unlimited current will flow through these diodes. If the
current is transient and limited to one hundred milliamps
or less, no damage to the device will occur.
Noise
The noise voltage of the LT6230/LT6231/LT6232 is equiva-
lent to that of a 75Ω resistor, and for the lowest possible
noise it is desirable to keep the source and feedback
resistance at or below this value, i.e. R
S
+ R
G
||R
FB
≤ 75Ω.
Figure 2. VS = ±2.5V, AV = 1 with Large Overdrive
1V/DIV
500µs/DIV
623012 F02
–2.5V
2.5V
0V
Figure 1. Simplified Schematic
ENABLE
DESD6
DESD5
–V
+V
+V
IN
–V
IN
+V
623012 F01
BIAS
DIFFERENTIAL
DRIVE GENERATOR
V
OUT
+V
C
M
I
1
–V
DESD3
–V
–V
DESD4
+V
DESD1
–V
DESD2
+V
D1
C1
D2
Q5
Q6
Q4
Q2
Q3
Q1
LT6230/LT6230-10/
LT6231/LT6232
18
sn623012 623012fas
APPLICATIO S I FOR ATIO
WUUU
With R
S
+ R
G
||R
FB
= 75Ω the total noise of the amplifier is:
e
N
=√(1.1nV)
2
+(1.1nV)
2
= 1.55nV/√Hz
Below this resistance value, the amplifier dominates the
noise, but in the region between 75Ω and about 3k, the
noise is dominated by the resistor thermal noise. As the
total resistance is further increased beyond 3k, the ampli-
fier noise current multiplied by the total resistance even-
tually dominates the noise.
The product of e
N
• √I
SUPPLY
is an interesting way to gauge
low noise amplifiers. Most low noise amplifiers with low
e
N
have high I
SUPPLY
current. In applications that require
low noise voltage with the lowest possible supply current,
this product can prove to be enlightening. The LT6230/
LT6231/LT6232 have an e
N
• √I
SUPPLY
product of only 1.9
per amplifier, yet it is common to see amplifiers with
similar noise specifications to have e
N
• √I
SUPPLY
as high
as 13.5.
For a complete discussion of amplifier noise, see the
LT1028 data sheet.
Enable Pin
The LT6230 includes an ENABLE pin that shuts down the
amplifier to 10µA maximum supply current. The ENABLE
pin must be driven high to within 0.35V of V
+
to shut down
the supply current. This can be accomplished with simple
gate logic; however care must be taken if the logic and the
LT6230 operate from different supplies. If this is the case,
then open drain logic can be used with a pull-up resistor
to ensure that the amplifier remains off. See Typical
Characteristic Curves.
The output leakage current when disabled is very low;
however, current can flow into the input protection diodes
D1 and D2 if the output voltage exceeds the input voltage
by a diode drop.
19
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
+
–
R2
732Ω
R4
10k
C3
0.1µF
EN
LT6230
f
0
= 1 = 1MHz
C = √C
1
C
2
, R = R1 = R2
f
0
=
(
732Ω
)
MHz, MAXIMUM f
0
= 1MHz
f
–3dB
=
f
0
A
V
= 20dB at f
0
E
N
= 4µV
RMS
INPUT REFERRED
I
S
= 3.7mA FOR V
+
= 5V
623012 F03
0.1µF
C2
47pF
C1
1000pF R3
10k
R1
732Ω
V
OUT
V
+
V
IN
2πRC
R
2.5
APPLICATIO S I FOR ATIO
WUUU
Single Supply, Low Noise, Low Power, Bandpass Filter with Gain = 10
Low Noise, Low Power, Single Supply, Instrumentation
Amplifier with Gain = 100
+
–
R14
2k
EN
U3
LT6230
VOUT = 100 (VIN2 – VIN1)
GAIN =
(
R2 + 1
)
(
R10
)
INPUT RESISTANCE = R5 = R6
f–3dB = 310Hz TO 11MHz
EN = 20µVRMS INPUT REFERRED
IS = 10.5mA FOR VS = 5V, 0V 623012 F05
C8
68pF
C3
1µF
R13
2k
R10
511Ω
R15
88.7Ω
R16
88.7Ω
R4
511Ω
R3
30.9Ω
R1
30.9ΩR2
511Ω
VOUT
VIN1
VIN2
V+
R1 R15
C9
68pF
R12
511Ω
+
–
EN
U2
LT6230-10
V+
C1
1µF
C2
2200pF
+
–
EN
U1
LT6230-10
V+
R5
511Ω
R6
511Ω
C4
10µF
R1 = R3
R2 = R4
R10 = R12
R15 = R16
FREQUENCY (Hz)
100k
GAIN (dB)
23
3
–7 1M 10M
623012 F04
Frequency Response Plot of
Bandpass Filter
LT6230/LT6230-10/
LT6231/LT6232
20
sn623012 623012fas
S6 Package
6-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1636)
1.50 – 1.75
(NOTE 4)
2.80 BSC
0.30 – 0.45
6 PLCS (NOTE 3)
DATUM ‘A’
0.09 – 0.20
(NOTE 3)
S6 TSOT-23 0302
2.90 BSC
(NOTE 4)
0.95 BSC
1.90 BSC
0.80 – 0.90
1.00 MAX 0.01 – 0.10
0.20 BSC
0.30 – 0.50 REF
PIN ONE ID
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
3.85 MAX
0.62
MAX 0.95
REF
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
1.4 MIN
2.62 REF
1.22 REF
U
PACKAGE DESCRIPTIO
21
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
DD Package
8-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1698)
3.00 ±0.10
(4 SIDES)
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON TOP AND BOTTOM OF PACKAGE
0.38 ± 0.10
BOTTOM VIEW—EXPOSED PAD
1.65 ± 0.10
(2 SIDES)
0.75 ±0.05
R = 0.115
TYP
2.38 ±0.10
(2 SIDES)
14
85
PIN 1
TOP MARK
(NOTE 6)
0.200 REF
0.00 – 0.05
(DD8) DFN 1203
0.25 ± 0.05
2.38 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
1.65 ±0.05
(2 SIDES)2.15 ±0.05
0.50
BSC
0.675 ±0.05
3.5 ±0.05
PACKAGE
OUTLINE
0.25 ± 0.05 0.50 BSC
U
PACKAGE DESCRIPTIO
LT6230/LT6230-10/
LT6231/LT6232
22
sn623012 623012fas
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.016 – .050
(0.406 – 1.270)
.010 – .020
(0.254 – 0.508)× 45°
0°– 8° TYP
.008 – .010
(0.203 – 0.254)
SO8 0303
.053 – .069
(1.346 – 1.752)
.014 – .019
(0.355 – 0.483)
TYP
.004 – .010
(0.101 – 0.254)
.050
(1.270)
BSC
1234
.150 – .157
(3.810 – 3.988)
NOTE 3
8765
.189 – .197
(4.801 – 5.004)
NOTE 3
.228 – .244
(5.791 – 6.197)
.245
MIN .160 ±.005
RECOMMENDED SOLDER PAD LAYOUT
.045 ±.005
.050 BSC
.030 ±.005
TYP
INCHES
(MILLIMETERS)
NOTE:
1. DIMENSIONS IN
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
U
PACKAGE DESCRIPTIO
23
sn623012 623012fas
LT6230/LT6230-10/
LT6231/LT6232
PACKAGE DESCRIPTIO
U
GN Package
16-Lead Plastic SSOP (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1641)
GN16 (SSOP) 0204
12
345678
.229 – .244
(5.817 – 6.198)
.150 – .157**
(3.810 – 3.988)
16 15 14 13
.189 – .196*
(4.801 – 4.978)
12 11 10 9
.016 – .050
(0.406 – 1.270)
.015 ± .004
(0.38 ± 0.10) × 45°
0° – 8° TYP
.007 – .0098
(0.178 – 0.249)
.0532 – .0688
(1.35 – 1.75)
.008 – .012
(0.203 – 0.305)
TYP
.004 – .0098
(0.102 – 0.249)
.0250
(0.635)
BSC
.009
(0.229)
REF
.254 MIN
RECOMMENDED SOLDER PAD LAYOUT
.150 – .165
.0250 BSC.0165 ±.0015
.045 ±.005
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
INCHES
(MILLIMETERS)
NOTE:
1. CONTROLLING DIMENSION: INCHES
2. DIMENSIONS ARE IN
3. DRAWING NOT TO SCALE
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 represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
LT6230/LT6230-10/
LT6231/LT6232
24
sn623012 623012fas
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
L INEAR TECHNOLOGY CO RPORATION 2003
LT/TP 0304 1K REV A • PRINTED IN USA
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LT1028 Single, Ultra Low Noise 50MHz Op Amp 0.85nV/√Hz
LT1677 Single, Low Noise Rail-to-Rail Amplifier 3V Operation, 2.5mA, 4.5nV/√Hz, 60µV Max V
OS
LT1806/LT1807 Single/Dual, Low Noise 325MHz Rail-to-Rail Amplifier 2.5V Operation, 550µV Max V
OS
, 3.5nV/√Hz
LT6200/LT6201 Single/Dual, Low Noise 165MHz 0.95nV√Hz, Rail-to-Rail Input and Output
LT6202/LT6203/LT6204 Single/Dual/Quad, Low Noise, Rail-to-Rail Amplifier 1.9nV/√Hz, 3mA Max, 100MHz Gain Bandwidth
Photodiode Amplifier Time Domain ResponseLow Power Avalanche Photodiode Transimpedance Amplifier
IS = 3.3mA
30mV/DIV
50ns/DIV
623012 TA02b
+
–
R1
1.5k
R2
1.5k
C2
0.1µF
5V
–5V
ENABLE
LT6230
≈ 200V BIAS
ADVANCED PHOTONIX
012-70-62-541
WWW.ADVANCEDPHOTONIX.COM
623012 TA02a
C1
4.7pF
OUTPUT OFFSET = 500µV TYPICAL
BANDWIDTH = 20MHz
OUTPUT NOISE = 1.1mV
P–P
(100MHz MEASUREMENT BW)
TYPICAL APPLICATIO S
U
The LT6230 is applied as a transimpedance amplifier with
an I-to-V conversion gain of 1.5kΩ set by R1.␣ The LT6230
is ideally suited to this application because of its low input
offset voltage and␣ current, and its low noise.␣ This is be-
cause the 1.5k resistor has an inherent thermal noise of
5nV/√Hz or 3.4pA/√Hz at room temperature, while the
LT6230␣ contributes only 1.1nV and 2.4pA /√Hz.␣ So, with
respect to both voltage and current noises, the LT6230 is
actually quieter than the gain resistor.
The circuit uses an avalanche photodiode with the cathode
biased to approximately 200V.␣ When light is incident on
the photodiode, it induces a current I
PD
which flows␣ into
the amplifier circuit. The amplifier output falls negative to
maintain balance at its inputs. The transfer function is
therefore V
OUT
= –I
PD
• 1.5k. C1 ensures stability and good
settling characteristics.␣ Output offset was measured
at␣ 280µV, so low in part because R2 serves to cancel the
DC effects of bias current.␣ Output noise was measured at
1.1mV
P–P
on a 100MHz measurement bandwidth, with C2
shunting R2’s thermal noise.␣ As shown in the scope
photo, the rise time is 17ns, indicating a signal bandwidth
of 20MHz.
