Specifications
| Type | Description |
|---|---|
| Part Number | INA281 |
| Manufacturer | Texas Instruments |
| Product Type | Operational Amplifier |
| Category | Signal Chain |
| Package / Case | DBV SOT-23, 5 pins, 2.90 mm × 1.60 mm nominal body |
| Operational common-mode voltage range | -4 V to +110 V; Device operating range |
| Survival common-mode voltage range | -20 V to +120 V; Survival voltage |
| DC common-mode rejection ratio | 120 dB; DC CMRR |
| AC common-mode rejection ratio | 65 dB; f = 50 kHz |
| Gain error | ±0.5% max; Specified accuracy feature |
| Gain drift | ±20 ppm/°C max; Specified accuracy feature |
| Offset voltage | ±55 µV typ; Specified accuracy feature |
| Offset drift | ±0.1 µV/°C typ; Specified accuracy feature |
| Available gains | 20, 50, 100, 200, 500 V/V; INA281A1/B1, A2/B2, A3/B3, A4/B4, A5/B5 respectively |
| Bandwidth | 1.3 MHz; High bandwidth feature |
| Slew rate | 2.5 V/µs; Rising edge |
| Quiescent current | 1.5 mA typ, 2 mA max; 2.25 mA max over temperature; VS = 5 V; TA = -40°C to +125°C for temperature max |
| Supply voltage absolute maximum | -0.3 V to 22 V; Absolute maximum rating over operating free-air temperature range |
| Differential input absolute maximum | -6 V to +6 V; INA281A5, INA281B5 |
| Differential input absolute maximum | -12 V to +12 V; All versions except INA281A5 and INA281B5 |
| Analog input common-mode absolute maximum | -20 V to +120 V; VIN+ and VIN- pins |
| Output voltage absolute maximum | GND - 0.3 V to VS + 0.3 V; Output pin |
| Operating temperature absolute maximum | -55°C to +150°C; Absolute maximum rating, TA |
| Junction temperature absolute maximum | 150°C; Absolute maximum rating, TJ |
| Storage temperature range | -65°C to +150°C; Absolute maximum rating, Tstg |
| ESD rating HBM | ±2000 V; Human body model per ANSI/ESDA/JEDEC JS-001, all pins |
| ESD rating CDM | ±1000 V; Charged device model per JEDEC JESD22-C101, all pins |
| Recommended common-mode input range | -4 V min, 48 V nom, 110 V max; Recommended operating conditions |
| Recommended operating supply range | 2.7 V min, 5 V nom, 20 V max; Recommended operating conditions |
| Recommended differential sense input range | 0 V to VS/G; Recommended operating conditions |
| Recommended ambient temperature | -40°C to +125°C; Recommended operating conditions |
| Junction-to-ambient thermal resistance | 184.7°C/W; DBV SOT-23, 5 pins |
| Junction-to-case top thermal resistance | 105.6°C/W; DBV SOT-23, 5 pins |
| Junction-to-board thermal resistance | 47.2°C/W; DBV SOT-23, 5 pins |
| Input offset voltage | ±100 µV typ, ±500 µV max; INA281x1, TA = 25°C, VS = 5 V, VSENSE = 0.5 V/Gain, VCM = 48 V |
| Input offset voltage | ±55 µV typ, ±300 µV max; INA281x2, TA = 25°C, VS = 5 V, VSENSE = 0.5 V/Gain, VCM = 48 V |
| Input offset voltage | ±30 µV typ, ±250 µV max; INA281x3, TA = 25°C, VS = 5 V, VSENSE = 0.5 V/Gain, VCM = 48 V |
| Input offset voltage | ±30 µV typ, ±200 µV max; INA281x4, TA = 25°C, VS = 5 V, VSENSE = 0.5 V/Gain, VCM = 48 V |
| Input offset voltage | ±15 µV typ, ±150 µV max; INA281x5, TA = 25°C, VS = 5 V, VSENSE = 0.5 V/Gain, VCM = 48 V |
| Power supply rejection ratio | ±1.5 µV/V typ, ±10 µV/V max; Input referred, 2.7 V ≤ VS ≤ 20 V, TA = -40°C to +125°C |
| Input bias current | 10 µA min, 20 µA typ, 30 µA max; IB+ and IB-, VSENSE = 0 V |
| Output swing to supply rail | VS - 0.07 V typ, VS - 0.15 V max; RLOAD = 10 kΩ, TA = -40°C to +125°C |
| Output swing to ground | 0.005 V typ, 0.02 V max; RLOAD = 10 kΩ, VSENSE = 0 V, TA = -40°C to +125°C |
| Maximum capacitive load | 500 pF; No sustained oscillations, no isolation resistor |
| Voltage noise density | 50 nV/√Hz; Electrical characteristics |
| Datasheet Status | request_only |
Product Overview
The INA281 is a Texas Instruments current-sense amplifier for Signal_Chain applications requiring current measurement over a wide common-mode voltage span. Its recommended common-mode input range is -4 V minimum, 48 V nominal, and 110 V maximum, while the survival common-mode voltage range extends from -20 V to +120 V.
Accuracy-related parameters include ±0.5% maximum gain error, ±20 ppm/°C maximum gain drift, and a specified offset-voltage feature of ±55 µV typical with ±0.1 µV/°C typical offset drift. Variant-specific input offset voltage ratings range from ±100 µV typical for INA281x1 down to ±15 µV typical for INA281x5 under the stated 25°C, 5 V, 48 V common-mode test condition.
The device is supplied in a DBV SOT-23, 5-pin package with a 2.90 mm × 1.60 mm nominal body. Recommended operation covers a 2.7 V to 20 V supply range and -40°C to +125°C ambient temperature. The extracted thermal data includes 184.7°C/W junction-to-ambient resistance for the DBV package.
Key Features
- -4 V to +110 V operational common-mode range
- -20 V to +120 V survival common-mode range
- 120 dB DC common-mode rejection ratio
- 65 dB AC CMRR at 50 kHz
- ±0.5% maximum gain error
- ±20 ppm/°C maximum gain drift
- 1.3 MHz bandwidth for current-sense signal paths
- 2.5 V/µs rising-edge slew rate
- 2.7 V to 20 V recommended supply range
- 500 pF maximum capacitive load without isolation resistor
Typical Applications
- Wide common-mode current sensing
- High-side current measurement
- Signal-chain current monitoring
- 48 V nominal bus sensing
- Gain-scaled sense voltage measurement
- Temperature-rated current measurement
- SOT-23 current-sense designs
Procurement Notes
When requesting a quote for INA281, 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 common-mode voltage range does the INA281 support?
The INA281 has an operational common-mode voltage range from -4 V to +110 V. Its survival common-mode voltage range is wider, from -20 V to +120 V, and the analog input common-mode absolute maximum is also listed as -20 V to +120 V.
What gain options are available for INA281 variants?
The available INA281 gains are 20, 50, 100, 200, and 500 V/V. These correspond respectively to INA281A1/B1, INA281A2/B2, INA281A3/B3, INA281A4/B4, and INA281A5/B5 variants.
What supply and temperature ranges are recommended for operation?
The recommended operating supply range is 2.7 V minimum, 5 V nominal, and 20 V maximum. The recommended ambient operating temperature range is -40°C to +125°C.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: June 30, 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.