LINEAR TECHNOLOGY LT1996 Technical data

RESISTOR MATCHING (%)

PERCENTAGE OF UNITS (%)

0.04

1996 TA01b

–0.02

0

0.02

40

35

30

25

20

15

10

5

0

–0.04

LT1996A
G = 81

FEATURES

■

Pin Configurable as a Difference Amplifier,
Inverting and Noninverting Amplifier

■

Difference Amplifier

Gain Range 9 to 117
CMRR >80dB

■

Noninverting Amplifier

Gain Range 0.008 to 118

■

Inverting Amplifier

Gain Range –0.08 to –117

■

Gain Error: <0.05%

■

Gain Drift: < 3ppm/°C

■

Wide Supply Range: Single 2.7V to Split ±18V

■

Micropower Operation: 100µA Supply

■

Input Offset Voltage: 50µV (Max)

■

Gain Bandwidth Product: 560kHz

■

Rail-to-Rail Output

■

Space Saving 10-Lead MSOP and DFN Packages

U

APPLICATIO S

LT1996

Precision, 100µA

Gain Selectable Amplifier

U

DESCRIPTIO

The LT®1996 combines a precision operational amplifier
with eight precision resistors to form a one-chip solution
for accurately amplifying voltages. Gains from –117 to
118 with a gain accuracy of 0.05% can be achieved without
any external components. The device is particularly well
suited for use as a difference amplifier, where the excellent
resistor matching results in a common mode rejection
ratio of greater than 80dB.

The amplifier features a 50µV maximum input offset
voltage and a gain bandwidth product of 560kHz. The
device operates from any supply voltage from 2.7V to 36V
and draws only 100µA supply current on a 5V supply. The
output swings to within 40mV of either supply rail.

The internal resistors have excellent matching character­istics; variation is 0.05% over temperature with a guaran­teed matching temperature coefficent of less than 3ppm/°C.
The resistors are also extremely stable over voltage,
exhibiting a nonlinearity of less than 10ppm.

■

Handheld Instrumentation

■

Medical Instrumentation

■

Strain Gauge Amplifiers

■

Differential to Single-Ended Conversion

, LTC and LT are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners. Patents Pending.

TYPICAL APPLICATIO

V

M(IN)

∆V

IN

V

P(IN)

INPUT RANGE
±60V

= 100kΩ

R

IN

The LT1996 is fully specified at 5V and ±15V supplies and
from –40°C to 85°C. The device is available in space
saving 10-lead MSOP and DFN packages. For an amplifier
with selectable gains from –13 to 14, see the LT1991 data
sheet.

U

Rail-to-Rail Gain = 9 Difference Amplifier Distribution of Resistor Matching

V

= V

REF

1996 TA01

+ 9 • ∆V

IN

1996f

1

V

REF

OUT

SWING 40mV TO
EITHER RAIL

15V

450k/81

450k/27

–

+

450k/9

–

450k/9

+

450k/27

450k/81

450k

4pF

LT1996

450k

4pF

–15V

LT1996

WW

W

ABSOLUTE AXI U RATI GS

U

(Note 1)

Total Supply Voltage (V+ to V–) ............................... 40V

Input Voltage (Pins P9/M9, Note 2) ....................... ±60V

Input Current

(Pins P27/M27/P81/M81, Note 2) .................. ±10mA

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

UUW

PACKAGE/ORDER I FOR ATIO

TOP VIEW

10

P9

1

P27

2

3

P81

4

V

EE

5

REF

10-LEAD (3mm × 3mm) PLASTIC DFN

UNDERSIDE METAL CONNECTED TO V

DD PACKAGE

T

= 125°C, θJA = 160°C/W

JMAX

(PCB CONNECTION OPTIONAL)

M9

M27

9

M81

8

7

V

CC

6

OUT

EE

ORDER PART

NUMBER

LT1996CDD
LT1996IDD
LT1996ACDD
LT1996AIDD

DD PART MARKING*

LBPC

Maximum Junction Temperature

DD Package ......................................................125°C

MS Package ..................................................... 150°C

Storage Temperature Range

DD Package .......................................–65°C to 125°C

MS Package ......................................–65°C to 150°C

MSOP–Lead Temperature (Soldering, 10 sec)...... 300°C

ORDER PART

NUMBER

TOP VIEW

1

P9

2

P27

3

P81

4

V

EE

REF

5

MS PACKAGE

10-LEAD PLASTIC MSOP

= 150°C, θJA = 230°C/W

JMAX

10

M9

9

M27

8

M81

7

V

CC

OUT

6

LT1996CMS
LT1996IMS
LT1996ACMS
LT1996AIMS

MS PART MARKING*T

LTBPB

*Temperature and electrical grades are identified by a label on the shipping container. Consult LTC Marketing for parts specified with wider operating temperature ranges.

ELECTRICAL CHARACTERISTICS

The

● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25°C. Difference amplifier configuration, VS = 5V, 0V or ±15V;
VCM = V

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

∆G Gain Error VS = ±15V, V

GNL Gain Nonlinearity VS = ±15V; V
∆G/∆T Gain Drift vs Temperature (Note 6) VS = ±15V; V
CMRR Common Mode Rejection Ratio, VS = ±15V; G = 9; VCM = ±15.3V

= half supply, unless otherwise noted.

REF

Referred to Inputs (RTI) LT1996AMS

= ±10V; RL = 10k
G = 81; LT1996AMS
G = 27; LT1996AMS
G = 9; LT1996AMS

G = 81; LT1996ADD ● ±0.02 ±0.05 %
G = 27; LT1996ADD
G = 9; LT1996ADD

G = 81; LT1996 ● ±0.04 ±0.12 %
G = 27; LT1996
G = 9; LT1996

LT1996ADD
LT1996

VS = ±15V; G = 27; VCM = –14.5V to 14.3V
LT1996AMS
LT1996ADD
LT1996

OUT

= ±10V; RL = 10k; G = 9 ● 1 10 ppm

OUT

= ±10V; RL = 10k ● 0.3 3 ppm/°C

OUT

● ±0.02 ±0.05 %

● ±0.03 ±0.06 %

● ±0.03 ±0.07 %

● ±0.02 ±0.07 %

● ±0.03 ±0.08 %

● ±0.04 ±0.12 %

● ±0.04 ±0.12 %

● 80 100 dB

● 80 100 dB

● 70 100 dB

● 95 105 dB

● 90 105 dB

● 75 105 dB

1996f

2

LT1996

ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25°C. Difference amplifier configuration, VS = 5V, 0V or ±15V;

= V

V

CM

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

CMRR Common Mode Rejection Ratio (RTI) VS = ±15V; G = 81; VCM = –14.1V to 13.9V

V

CM

V

OS

∆VOS/∆T Op Amp Offset Voltage Drift (Note 6) ● 0.3 1 µV/°C
I

B

I

OS

e

n

R

IN

= half supply, unless otherwise noted.

REF

Input Voltage Range (Note 7) P9/M9 Inputs

Op Amp Offset Voltage (Note 8) LT1996AMS, VS = 5V, 0V 15 50 µV

Op Amp Input Bias Current 2.5 5 nA

Op Amp Input Offset Current LT1996A 50 500 pA

Op Amp Input Noise Voltage 0.01Hz to 1Hz 0.35 µV

Input Noise Voltage Density G = 9; f = 1kHz 46 nV/√Hz
(Includes Resistor Noise) G = 117; f = 1kHz 18 nV/√Hz

Input Impedance (Note 10) P9 (M9 = Ground) ● 350 500 650 kΩ

LT1996AMS
LT1996ADD
LT1996

= ±15V; V

V

S

V

= 5V, 0V; V

S

= 3V, 0V; V

V

S

= 0V ● –15.5 15.3 V

REF

= 2.5V ● 0.84 3.94 V

REF

= 1.25V ● 0.98 1.86 V

REF

● 105 120 dB

● 100 120 dB

● 85 120 dB

P9/M9 Inputs, P81/M81 Connected to REF
V

= ±15V; V

S

= 5V, 0V; V

V

S

= 3V, 0V; V

V

S

= 0V ● –60 60 V

REF

= 2.5V ● –12.6 15.6 V

REF

= 1.25V ● –1.25 6.8 V

REF

P27/M27 Inputs

= ±15V; V

V

S

= 5V, 0V; V

V

S

V

= 3V, 0V; V

S

= 0V ● –14.5 14.3 V

REF

= 2.5V ● 0.95 3.84 V

REF

= 1.25V ● 1 1.82 V

REF

P81/M81 Inputs

= ±15V; V

V

S

= 5V, 0V; V

V

S

V

= 3V, 0V; V

S

= 0V ● –14.1 13.9 V

REF

= 2.5V ● 0.99 3.81 V

REF

= 1.25V ● 1 1.8 V

REF

● 135 µV

LT1996AMS, VS = ±15V 15 80 µV

● 160 µV

LT1996MS 25 100 µV

● 200 µV

LT1996DD 25 150 µV

● 250 µV

● 7.5 nA

● 750 pA

LT1996 50 1000 pA

● 1500 pA

0.01Hz to 1Hz 0.07 µV

0.1Hz to 10Hz 0.25 µV

0.1Hz to 10Hz 0.05 µV

P27 (M27 = Ground)
P81 (M81 = Ground)

● 326.9 467 607.1 kΩ

● 319.2 456 592.8 kΩ

P-P

RMS

P-P

RMS

M9 (P9 = Ground) ● 35 50 65 kΩ
M27 (P27 = Ground)
M81 (P81 = Ground)

● 11.69 16.7 21.71 kΩ

● 3.85 5.5 7.15 kΩ

1996f

3

LT1996

ELECTRICAL CHARACTERISTICS

temperature range, otherwise specifications are at T
VCM = V

= half supply, unless otherwise noted.

REF

The ● denotes the specifications which apply over the full operating

= 25°C. Difference amplifier configuration, VS = 5V, 0V or ±15V;

A

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

∆R Resistor Matching (Note 9) G = 81; LT1996AMS ● ±0.02 ±0.05 %

G = 27; LT1996AMS
G = 9; LT1996AMS

● ±0.03 ±0.06 %

● ±0.03 ±0.07 %

G = 81; LT1996ADD ● ±0.02 ±0.05 %
G = 27; LT1996ADD
G = 9; LT1996ADD

● ±0.02 ±0.07 %

● ±0.03 ±0.08 %

G = 81; LT1996 ● ±0.04 ±0.12 %
G = 27; LT1996
G = 9; LT1996

● ±0.04 ±0.12 %

● ±0.04 ±0.12 %

∆R/∆T Resistor Temperature Coefficient (Note 6) Resistor Matching ● 0.3 3 ppm/°C

Absolute Value

● –30 ppm/°C

PSRR Power Supply Rejection Ratio VS = ±1.35V to ±18V (Note 8) ● 105 135 dB

Minimum Supply Voltage ● 2.4 2.7 V

V

OUT

Output Voltage Swing (to Either Rail) No Load

= 5V, 0V 40 55 mV

V

S

V

= 5V, 0V ● 65 mV

S

= ±15V ● 110 mV

V

S

1mA Load
V

= 5V, 0V 150 225 mV

S

= 5V, 0V ● 275 mV

V

S

= ±15V ● 300 mV

V

S

I

SC

Output Short-Circuit Current (Sourcing) Drive Output Positive; 8 12 mA

Short Output to Ground

● 4mA

Output Short-Circuit Current (Sinking) Drive Output Negative; 8 21 mA

Short Output to V

or Midsupply ● 4mA

S

BW –3dB Bandwidth G = 9 38 kHz

G = 27 17 kHz
G = 81 7 kHz

GBWP Op Amp Gain Bandwidth Product f = 10kHz 560 kHz
tr, t

f

Rise Time, Fall Time G = 9; 0.1V Step; 10% to 90% 8 µs

G = 81; 0.1V Step; 10% to 90% 40 µs

t

S

SR Slew Rate VS = 5V, 0V; V

I

S

Settling Time to 0.01% G = 9; VS = 5V, 0V; 2V Step 85 µs

G = 9; V
G = 9; V
G = 9; V

V

= 5V, 0V; –2V Step 85 µs

S

= ±15V; 10V Step 110 µs

S

= ±15V; –10V Step 110 µs

S

= 1V to 4V ● 0.06 0.12 V/µs

= ±15V; V

S

OUT

= ±10V ● 0.08 0.12 V/µs

OUT

Supply Current VS = 5V, 0V 100 110 µA

● 150 µA

VS = ±15V 130 160 µA

● 210 µA

Note 1: Absolute Maximum Ratings are those beyond which the life of the
device may be impaired.

Note 2: The P27/M27 and P81/M81 inputs are protected by ESD diodes to
the supply rails. If one of these four inputs goes outside the rails, the input
current should be limited to less than 10mA. The P9/M9 inputs can

4

withstand ±60V if P81/M81 are grounded and VS = ±15V (see Applications
Information section about “High Voltage CM Difference Amplifiers”).

Note 3: A heat sink may be required to keep the junction temperature
below absolute maximum ratings.

1996f

GAIN (V/V)

9

INPUT OFFSET VOLTAGE (µV)

150

100

50

0

–50

–100

–150

10881 90 99 11745

1996 G06

18 27 72635436

VS = 5V, 0V
REPRESENTATIVE PARTS

ELECTRICAL CHARACTERISTICS

LT1996

Note 4: Both the LT1996C and LT1996I are guaranteed functional over the
–40°C to 85°C temperature range.

Note 5: The LT1996C is guaranteed to meet the specified performance
from 0°C to 70°C and is designed, characterized and expected to meet
specified performance from –40°C to 85°C but is not tested or QA
sampled at these temperatures. The LT1996I is guaranteed to meet
specified performance from –40°C to 85°C.

Note 6: This parameter is not 100% tested.
Note 7: Input voltage range is guaranteed by the CMRR test at V

= ±15V.

S

For the other voltages, this parameter is guaranteed by design and through
correlation with the ±15V test. See the Applications Information section to

determine the valid input voltage range under various operating
conditions.

Note 8: Offset voltage, offset voltage drift and PSRR are defined as
referred to the internal op amp. You can calculate output offset as follows.
In the case of balanced source resistance, V
I

• 450k + IB • 450k • (1 – RP/RN) where RP and RN are the total

OS

resistance at the op amp positive and negative terminal respectively.
Note 9: Resistors connected to the minus inputs. Resistor matching is not

tested directly, but is guaranteed by the gain error test.
Note 10: Input impedance is tested by a combination of direct

measurements and correlation to the CMRR and gain error tests.

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Output Voltage Swing vs

Supply Current vs Supply Voltage

200

175

150

125

100

SUPPLY CURRENT (µA)

TA = 25°C

75

50

25

0

42 6 10 14 18

0

SUPPLY VOLTAGE (±V)

8

TA = 85°C

12

TA = –40°C

16

1996 G01

20

Temperature

VS = 5V, 0V
NO LOAD

60

40

OUTPUT LOW

OUTPUT VOLTAGE SWING (mV)

(LEFT AXIS)

20

V

EE

–50

050

–25 25 75 125

TEMPERATURE (°C)

OUTPUT HIGH
(RIGHT AXIS)

OS, OUT

(Difference Amplifier Configuration)

Output Voltage Swing vs Load
Current (Output Low)

V

CC

1400

–20

–40

–60

100

1996 G02

VS = 5V, 0V

1200

1000

800

600

400

OUTPUT VOLTAGE (mV)

200

V

EE

0

1

TA = 25°C

2

34

LOAD CURRENT (mA)

= VOS • Noise Gain +

TA = 85°C

TA = –40°C

1098765

1996 G03

Output Voltage Swing vs Load
Current (Output High)

V

CC

–100

–200

–300

–400

–500

–600

–700

–800

OUTPUT VOLTAGE SWING (mV)

–900

–1000

0123

TA = 85°C

TA = 25°C

4

5

LOAD CURRENT (mA)

VS = 5V, 0V

TA = –40°C

678910

1996 G04

Output Short-Circuit Current vs
Temperature

25

VS = 5V, 0V

20

15

10

SOURCING

5

OUTPUT SHORT-CIRCUIT CURRENT (mA)

0

–50

0

–25

TEMPERATURE (°C)

SINKING

50

25

75

100

Input Offset Voltage vs
Difference Gain

125

1996 G05

1996f

5

LT1996

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Output Offset Voltage vs
Difference Gain Gain Error vs Load Current Slew Rate vs Temperature

10.0

7.5

5.0

2.5

0

–2.5

–5.0

OUTPUT OFFSET VOLTAGE (mV)

–7.5

–10.0

18 27 72635436

9

VS = 5V, 0V
REPRESENTATIVE PARTS

10881 90 99 11745

GAIN (V/V)

1996 G07

Bandwidth vs Gain CMRR vs Frequency PSRR vs Frequency

40

35

30

25

20

15

–3dB BANDWIDTH (kHz)

10

5

0

27 45 63 81

9

GAIN (V/V)

VS = 5V, 0V

= 25°C

T

A

99 11718 36 54 72 90 108

1996 G10

0.04
GAIN = 81

= ±15V

V

S

0.03
V

= ±10V

OUT

= 25°C

T

A

0.02

0.01

0

–0.01

GAIN ERROR (%)

–0.02

–0.03

–0.04

130
120
110
100

90
80
70
60

CMRR (dB)

50
40
30
20
10

0

12 4

0

GAIN = 81

GAIN = 27

GAIN = 9

10 1k 10k 1M

100 100k

REPRESENTATIVE UNITS

3

LOAD CURRENT (mA)

FREQUENCY (Hz)

(Difference Amplifier Configuration)

0.30
GAIN = 9

= ±15V

V

S

= ±10V

V

0.25

OUT

0.20

0.15

0.10

SLEW RATE (V/µs)

0.05

0

–50

–25 0

120

110

100

90

80

70

60

50

40

30

20

10

0

10 1k 10k

1996 G08

VS = 5V, 0V

= 25°C

T

A

1996 G11

5

PSRR (dB)

SR– (FALLING EDGE)

TEMPERATURE (°C)

100 100k

FREQUENCY (Hz)

SR+ (RISING EDGE)

50 100 125

25 75

GAIN = 9

GAIN = 27

1996 G09

VS = 5V, 0V

= 25°C

T

A

GAIN = 81

1996 G12

Output Impedance vs Frequency CMRR vs Temperature Gain Error vs Temperature

1000

VS = 5V, 0V

= 25°C

T

A

100

10

GAIN = 81

1

GAIN = 27

OUTPUT IMPEDANCE (Ω)

0.01

GAIN = 9

0.1

1 100 1k 100k10k

10

FREQUENCY (Hz)

1996 G13

120

GAIN = 9
V

100

80

60

CMRR (dB)

40

20

0

–50

= ±15V

S

–25 0

REPRESENTATIVE UNITS

50 100 125

25 75

TEMPERATURE (°C)

1996 G14

0.030
GAIN = 9

= ±15V

V

S

0.025

0.020

0.015

GAIN ERROR (%)

0.010

0.005

0

–50

–25 0

TEMPERATURE (°C)

6

REPRESENTATIVE UNITS

50 100 125

25 75

1996 G15

1996f

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LT1996

(Difference Amplifier Configuration)

50

40

30

GAIN (dB)

20

10

0

0.5 10 100 5001

50mV/DIV

VS = 5V, 0V
TA = 25°C

GAIN = 81

GAIN = 27

GAIN = 9

FREQUENCY (kHz)

1996 G16

Small Signal Transient Response,
Gain = 9

Gain and Phase vs FrequencyGain vs Frequency

40

PHASE
(RIGHT AXIS)

30

20

GAIN
(LEFT AXIS)

GAIN (dB)

10

0

–10

0.1

50mV/DIV

1996 G17

400

0

–20

–40

–60

–80

–100

–120

–140

–160

–180

–200

1

FREQUENCY (kHz)

10 100

VS = 5V, 0V
TA = 25°C
GAIN = 9

Small Signal Transient Response,
Gain = 27

0.01Hz to 1Hz Voltage Noise

VS = ±15V

= 25°C

T

A

MEASURED IN G =117
REFERRED TO OP AMP INPUTS

PHASE (deg)

OP AMP VOLTAGE NOISE (100nV/DIV)

0 102030405060 70 8090100

Small Signal Transient Response,
Gain = 81

50mV/DIV

TIME (s)

1996 G21

10µs/DIV

U

UU

PI FU CTIO S

(Difference Amplifier Configuration)

1996 G18

P9 (Pin 1): Noninverting Gain-of-9 input. Connects a 50k
internal resistor to the op amp’s noninverting input.

P27 (Pin 2): Noninverting Gain-of-27 input. Connects a
(50k/3) internal resistor to the op amp’s noninverting input.

P81 (Pin 3): Noninverting Gain-of-81 input. Connects a
(50k/9) internal resistor to the op amp’s noninverting input.

VEE (Pin 4): Negative Power Supply. Can be either ground
(in single supply applications), or a negative voltage (in
split supply applications).

REF (Pin 5): Reference Input. Sets the output level when
difference between inputs is zero. Connects a 450k internal

20µs/DIV

1996 G19

50µs/DIV

1996 G20

resistor to the op amp’s noninverting input.

OUT (Pin 6): Output. V
(V

– VM3) + 81 • (VP9 – VM9).

P3

OUT

= V

+ 9 • (VP1 – VM1) + 27 •

REF

VCC (Pin 7): Positive Power Supply. Can be anything from

2.7V to 36V above the VEE voltage.

M81 (Pin 8): Inverting Gain-of-81 input. Connects a
(50k/9) internal resistor to the op amp’s inverting input.

M27 (Pin 9): Inverting Gain-of-27 input. Connects a
(50k/3) internal resistor to the op amp’s inverting input.

M9 (Pin 10): Inverting Gain-of-9 input. Connects a 50k
internal resistor to the op amp’s inverting input.

1996f

7

LT1996

BLOCK DIAGRA

W

9 8

M9 M27 M81

450k/81

450k/27

450k/9

450k/9

450k/27

450k/81

P9 P27 P81

2 3 4 5

1

U

WUU

APPLICATIO S I FOR ATIO

Introduction

The LT1996 may be the last op amp you ever have to stock.
Because it provides you with several precision matched
resistors, you can easily configure it into several different
classical gain circuits without adding external compo­nents. The several pages of simple circuits in this data
sheet demonstrate just how easy the LT1996 is to use. It
can be configured into difference amplifiers, as well as into
inverting and noninverting single ended amplifiers. The
fact that the resistors and op amp are provided together in
such a small package will often save you board space and
reduce complexity for easy probing.

The Op Amp

The op amp internal to the LT1996 is a precision device
with 15µV typical offset voltage and 3nA input bias cur-
rent. The input offset current is extremely low, so match­ing the source resistance seen by the op amp inputs will
provide for the best output accuracy. The op amp inputs
are not rail-to-rail, but extend to within 1.2V of VCC and 1V

7 610

4pF

–

+

4pF

OUT

V

450k

V

EE

CC

450k

OUT

LT1996

REF

1996 BD

of VEE. For many configurations though, the chip inputs
will function rail-to-rail because of effective attenuation to
the +input. The output is truly rail-to-rail, getting to within
40mV of the supply rails. The gain bandwidth product of
the op amp is about 560kHz. In noise gains of 2 or more,
it is stable into capacitive loads up to 500pF. In noise gains
below 2, it is stable into capacitive loads up to 100pF.

The Resistors

The resistors internal to the LT1996 are very well matched
SiChrome based elements protected with barrier metal.
Although their absolute tolerance is fairly poor (±30%),
their matching is to within 0.05%. This allows the chip to
achieve a CMRR of 80dB, and gain errors within 0.05%.
The resistor values are (450k/9), (450k/27), (450k/81)
and 450k, connected to each of the inputs. The resistors
have power limitations of 1watt for the 450k and (450k/81)
resistors, 0.3watt for the (450k/27) resistors and 0.5watt
for the (450k/9) resistors; however, in practice, power
dissipation will be limited well below these values by the

8

1996f