Specifications
| Type | Description |
|---|---|
| Part Number | INA821 |
| Manufacturer | Texas Instruments |
| Product Type | Operational Amplifier |
| Category | Signal Chain |
| Package Case | 8-pin SOIC 4.90 mm x 3.91 mm; 8-pin VSSOP 3.00 mm x 3.00 mm; 8-pin WSON 3.00 mm x 3.00 mm |
| Input Stage Offset Voltage | 10 µV typ, 35 µV max; INA821ID and INA821DRG, TA=25°C, VS=±15 V, RL=10 kΩ, VREF=0 V, G=1 |
| Input Stage Offset Voltage | 10 µV typ, 40 µV max; INA821IDGK, TA=25°C, VS=±15 V, RL=10 kΩ, VREF=0 V, G=1 |
| Input Stage Offset Voltage Over Temperature | 75 µV max; INA821ID and INA821DRG, TA=-40°C to +125°C |
| Input Stage Offset Voltage Over Temperature | 80 µV max; INA821IDGK, TA=-40°C to +125°C |
| Input Stage Offset Voltage Drift | 0.1 µV/°C typ, 0.4 µV/°C max; TA=-40°C to +125°C |
| Output Stage Offset Voltage | 50 µV typ, 350 µV max; INA821ID and INA821DGK, TA=25°C |
| Output Stage Offset Voltage | 50 µV typ, 400 µV max; INA821DRG, TA=25°C |
| Output Stage Offset Voltage Over Temperature | 850 µV max; TA=-40°C to +125°C |
| Output Stage Offset Voltage Drift | 5 µV/°C typ; TA=-40°C to +125°C |
| Power Supply Rejection Ratio | 110 dB min, 120 dB typ; G=1, RTI |
| Power Supply Rejection Ratio | 114 dB min, 130 dB typ; G=10, RTI |
| Power Supply Rejection Ratio | 130 dB min, 135 dB typ; G=100, RTI |
| Power Supply Rejection Ratio | 136 dB min, 140 dB typ; G=1000, RTI |
| Differential Input Impedance | 100 GΩ || 1 pF; TA=25°C, VS=±15 V, G=1 |
| Common-Mode Input Impedance | 100 GΩ || 7 pF; TA=25°C, VS=±15 V, G=1 |
| RFI Filter -3 dB Frequency | 45 MHz; input RFI filter |
| Operating Input Range | (V-) + 2 V to (V+) - 2 V; VS=±2.25 V to ±18 V |
| Input Overvoltage Range | ±40 V; TA=-40°C to +125°C |
| Common-Mode Rejection Ratio | 92 dB min, 105 dB typ; DC to 60 Hz, RTI, VCM=(V-)+2 V to (V+)-2 V, G=1 |
| Common-Mode Rejection Ratio | 112 dB min, 125 dB typ; DC to 60 Hz, RTI, VCM=(V-)+2 V to (V+)-2 V, G=10 |
| Common-Mode Rejection Ratio | 132 dB min, 145 dB typ; DC to 60 Hz, RTI, VCM=(V-)+2 V to (V+)-2 V, G=100 |
| Common-Mode Rejection Ratio | 140 dB min, 150 dB typ; DC to 60 Hz, RTI, VCM=(V-)+2 V to (V+)-2 V, G=1000 |
| Input Bias Current | 0.15 nA typ, 0.5 nA max; VCM=VS/2, TA=25°C |
| Input Bias Current Over Temperature | 2 nA max; VCM=VS/2, TA=-40°C to +125°C |
| Input Offset Current | 0.15 nA typ, 0.5 nA max; VCM=VS/2, TA=25°C |
| Input Offset Current Over Temperature | 2 nA max; VCM=VS/2, TA=-40°C to +125°C |
| Input Stage Voltage Noise | 7 nV/√Hz; f=1 kHz, G=100, RS=0 Ω |
| Input Stage Voltage Noise | 0.14 µVPP; fB=0.1 Hz to 10 Hz, G=100, RS=0 Ω |
| Output Stage Voltage Noise | 65 nV/√Hz; f=1 kHz, RS=0 Ω |
| Output Stage Voltage Noise | 2.5 µVPP; fB=0.1 Hz to 10 Hz, RS=0 Ω |
| Noise Current | 130 fA/√Hz; f=1 kHz |
| Noise Current | 4.7 pAPP; fB=0.1 Hz to 10 Hz, G=100 |
| Gain Equation | G = 1 + (49.4 kΩ / RG); external gain resistor between RG pins |
| Gain Range | 1 to 10000 V/V; external gain resistor configured |
| Gain Error | ±0.005% typ, ±0.025% max; G=1, VO=±10 V |
| Gain Error | ±0.025% typ, ±0.15% max; G=10, VO=±10 V |
| Gain Error | ±0.025% typ, ±0.15% max; G=100, VO=±10 V |
| Gain Error | ±0.05% typ; G=1000, VO=±10 V |
| Gain Drift | ±5 ppm/°C max; G=1, TA=-40°C to +125°C |
| Gain Drift | ±35 ppm/°C max; G>1, TA=-40°C to +125°C; excludes external gain resistor effects |
| Gain Nonlinearity | 1 ppm typ, 10 ppm max; G=1 to 10, VO=-10 V to 10 V, RL=10 kΩ |
| Gain Nonlinearity | 15 ppm max; G=100, VO=-10 V to 10 V, RL=10 kΩ |
| Gain Nonlinearity | 10 ppm max; G=1000, VO=-10 V to 10 V, RL=10 kΩ |
| Gain Nonlinearity | 30 ppm max; G=1 to 100, VO=-10 V to 10 V, RL=2 kΩ |
| Output Voltage Swing | (V-) + 0.15 V to (V+) - 0.15 V; TA=25°C, VS=±15 V, RL=10 kΩ, G=1 |
| Load Capacitance Stability | 1000 pF; stable capacitive load |
| Closed-Loop Output Impedance | 1.3 Ω; f=10 kHz |
| Short-Circuit Current | ±20 mA; continuous to VS/2 |
| Bandwidth | 4.7 MHz; G=1, -3 dB |
| Bandwidth | 970 kHz; G=10, -3 dB |
| Bandwidth | 290 kHz; G=100, -3 dB |
| Bandwidth | 30 kHz; G=1000, -3 dB |
| Slew Rate | 2.0 V/µs; G=1, VO=±10 V |
| Settling Time | 6 µs; 0.01%, G=1 to 100, VSTEP=10 V |
| Settling Time | 40 µs; 0.01%, G=1000, VSTEP=10 V |
| Settling Time | 10 µs; 0.001%, G=1 to 100, VSTEP=10 V |
| Settling Time | 50 µs; 0.001%, G=1000, VSTEP=10 V |
| Reference Input Impedance | 10 kΩ; REF pin |
| Reference Input Voltage Range | (V-) to (V+); REF pin |
| Reference Gain to Output | 1 V/V; REF pin to output |
| Reference Gain Error | 0.01%; REF pin to output |
| Single-Supply Voltage Range | 4.5 V min, 36 V max; recommended operating conditions |
| Dual-Supply Voltage Range | ±2.25 V min, ±18 V max; recommended operating conditions |
| Quiescent Current | 600 µA typ, 650 µA max; VIN=0 V, TA=25°C |
| Quiescent Current Over Temperature | 870 µA max; VIN=0 V, TA=-40°C to +125°C |
| Specified Temperature Range | -40°C to +125°C; recommended operating conditions |
| Absolute Maximum Supply Voltage | -20 V to 20 V; operating free-air temperature range |
| Absolute Maximum Signal Input Voltage | -40 V to 40 V; signal input pins |
| Absolute Maximum REF Pin Voltage | -20 V to 20 V; REF pin |
| Absolute Maximum Signal Output Voltage | (−VS) − 0.5 V to (+VS) + 0.5 V; signal output pins |
| Junction Temperature | 175°C max; absolute maximum rating |
| Storage Temperature | -65°C to +150°C; absolute maximum rating |
| HBM ESD Rating | ±1500 V; human-body model per ANSI/ESDA/JEDEC JS-001 |
| CDM ESD Rating | ±750 V; charged-device model per JEDEC JESD22-C101 |
| SOIC Thermal Resistance Junction-to-Ambient | 119.6°C/W; D package, 8 pins |
| VSSOP Thermal Resistance Junction-to-Ambient | 215.4°C/W; DGK package, 8 pins |
| WSON Thermal Resistance Junction-to-Ambient | 55.6°C/W; DRG package, 8 pins |
| Pin 1 Function | Negative inverting input; -IN pin |
| Pin 4 Function | Positive noninverting input; +IN pin |
| Pin 7 Function | Output; OUT pin |
| Gain Resistor Pins | Pins 2 and 3; place gain resistor between pin 2 and pin 3 |
| Reference Pin Requirement | Must be driven by a low impedance source; REF pin, pin 6 |
| Datasheet Status | request_only |
Product Overview
The INA821 is a Texas Instruments precision instrumentation amplifier for Signal_Chain designs requiring differential input amplification with externally configured gain. Pins 2 and 3 accept the gain resistor, and the gain equation is G = 1 + (49.4 kΩ / RG), allowing a gain range from 1 to 10000 V/V.
Electrical limits include 10 µV typical input stage offset voltage at G=1, 0.1 µV/°C typical input offset drift, input bias current of 0.15 nA typical, and input stage voltage noise of 7 nV/√Hz at 1 kHz with G=100. CMRR ranges from 92 dB minimum at G=1 to 140 dB minimum at G=1000, while PSRR ranges from 110 dB minimum at G=1 to 136 dB minimum at G=1000.
The device is available in 8-pin SOIC, VSSOP, and WSON packages. It operates from 4.5 V to 36 V single supply or ±2.25 V to ±18 V dual supply over -40°C to +125°C. The REF pin has 10 kΩ input impedance, 1 V/V gain to output, and must be driven by a low impedance source.
Key Features
- Precision instrumentation amplifier for Signal_Chain designs
- Gain range from 1 to 10000 V/V
- External gain resistor uses G = 1 + 49.4 kΩ/RG
- 10 µV typical input stage offset voltage
- 7 nV/√Hz input stage voltage noise at 1 kHz
- 4.7 MHz bandwidth at gain of 1
- Single-supply operation from 4.5 V to 36 V
- Dual-supply operation from ±2.25 V to ±18 V
- Input overvoltage range is ±40 V
- Specified temperature range is -40°C to +125°C
Typical Applications
- Instrumentation amplifier circuits
- Differential input measurement
- Precision signal-chain amplification
- High-gain signal conditioning
- Low-noise signal amplification
- Single-supply analog front ends
- Dual-supply analog front ends
Procurement Notes
When requesting a quote for INA821, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For analog and signal-chain sourcing, supply voltage, bandwidth, accuracy, noise level, package, temperature grade, input/output configuration and qualification requirements should be verified before approval.
FAQ
What type of device is the INA821?
The INA821 is a Texas Instruments precision instrumentation amplifier in the Signal_Chain category. Its gain is set with an external resistor between pins 2 and 3 using G = 1 + (49.4 kΩ / RG).
What supply ranges does the INA821 support?
The INA821 supports 4.5 V to 36 V single-supply operation and ±2.25 V to ±18 V dual-supply operation under recommended operating conditions. The specified temperature range is -40°C to +125°C.
What packages are listed for the INA821?
The listed package options are 8-pin SOIC measuring 4.90 mm x 3.91 mm, 8-pin VSSOP measuring 3.00 mm x 3.00 mm, and 8-pin WSON measuring 3.00 mm x 3.00 mm.
How should the INA821 REF pin be handled?
The REF pin is pin 6 and must be driven by a low impedance source. Its input impedance is 10 kΩ, its input voltage range is from V- to V+, and its gain to the output is 1 V/V.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 8, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.