INA131AP - Precision G=100 Instrumentation Amp | Texas Instruments
MPN： INA131AP ✓ 啟用中INA131AP 概覽
An instrumentation amplifier is a specialized analog amplifier optimized for amplifying the difference between two input signals while rejecting voltage common to both inputs. Within the signal-conditioning hierarchy, an instrumentation amplifier is a precision analog IC used for current sensing, bridge excitation, biomedical instrumentation, and industrial measurement. Its internal differential input and feedback arrangement generally provides better common-mode rejection and offset behavior than a conventional op-amp circuit configured for the same function.
The INA131AP provides a fixed gain of 100, allowing small differential sensor outputs to be raised to a level suitable for an ADC without an external gain-setting network. Maximum input offset voltage is 125 µV, while input bias current is specified at no more than 2 nA. Input overvoltage protection extends to ±40 V, helping the amplifier tolerate transient voltage at sensor inputs. The listed operating range of ±2.25 V to ±18 V supports dual-supply operation across common industrial and instrumentation systems.
Internally, the INA131 uses a three-op-amp instrumentation-amplifier architecture. This arrangement provides high input impedance, differential gain of 100, and strong rejection of common-mode signals. The listed 106 dB CMRR is particularly useful when the measured differential signal is much smaller than the voltage shared by both input terminals. A slew rate of 0.7 V/µs and bandwidth of 70 kHz define its response for low-frequency industrial, measurement, and control signals.
Typical uses include precision current sensing, bridge-based pressure and strain measurement, low-level differential sensor interfaces, analog signal conditioning, and buffered measurement channels. The fixed gain also simplifies system calibration because engineers do not need to select or adjust an external precision gain resistor. The 8-pin PDIP package is particularly useful for prototypes, laboratory equipment, legacy industrial systems, and designs assembled through through-hole manufacturing processes.
Designers should preserve the input common-mode range and supply headroom for the selected output voltage. Because the gain is fixed at 100, input signals must remain small enough to prevent saturation, while source impedance and sensor grounding can influence offset and bias-current error. The INA131AP is non-isolated and operates from a bipolar supply, so system power architecture, grounding, transient protection, and input filtering should be reviewed before deployment.
This product page consolidates the verified distributor data, manufacturer resources, package information, procurement details, and engineering guidance for the INA131AP. It also distinguishes verified drop-in candidates from cross-reference search results, helping engineers evaluate PCB compatibility and device-level limitations rather than relying only on the “instrumentation amplifier” device category.
直接替換替代品，適用於 INA131AP — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
INA131AP-1
✅ 直接替換📋 參考替代品（不在目錄中）
INA131BPG4
✅ 直接替換📋 參考替代品（不在目錄中）
LT1012IN8#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
AMP04FPZ
✅ 直接替換📋 參考替代品（不在目錄中）
INA131AP 最大額定值與電氣特性
| Amplifier Type | Precision fixed-gain instrumentation amplifier |
| Number of Circuits | 1 circuit |
| Gain | 100 V/V |
| Bandwidth | 70 kHz |
| Slew Rate | 0.7 V/µs |
| Input Offset Voltage | 125 µV maximum |
| Input Offset Voltage Drift | 0.25 µV/°C maximum |
| Input Bias Current | 2 nA maximum |
| Common-Mode Rejection Ratio | 106 dB |
| Input Overvoltage Protection | ±40 V |
| Supply Voltage Range | ±2.25 V to ±18 V |
| Internal Architecture | 3-op-amp instrumentation amplifier |
| 封裝 | 8-pin PDIP |
| 安裝類型 | Through-hole |
INA131AP 8-pin pdip 腳位配置指南
INA131AP（8-pin pdip 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： INA131AP.
請參閱 資料表 以查看完整腳位配置。
典型應用
INA131AP 適用於 6 應用s: Precision Current Sensing, Bridge Sensor Signal Conditioning, Industrial Analog Measurement, Medical Instrument Front End, Strain and Pressure Measurement, Legacy Laboratory and Data Acquisition.
Precision Current Sensing
The INA131AP fits low-side current sensing when the shunt differential voltage is small and substantial common-mode voltage must be rejected. Its fixed gain of 100 amplifies the shunt output directly for an ADC, while the 106 dB CMRR helps suppress supply and bus disturbances that affect both input terminals. The 125 µV maximum input offset is important because it appears as 12.5 mV at the output after gain of 100. Designers must keep the shunt signal below output saturation, check the common-mode range, and account for input bias current of no more than 2 nA.
推薦
Bridge Sensor Signal Conditioning
The INA131AP is appropriate for differential bridge outputs where the wanted sensor signal is much smaller than the common-mode voltage present on both inputs. Gain of 100 increases the bridge signal by a known factor, while 106 dB CMRR suppresses common-mode errors that could otherwise dominate the measurement. Its 125 µV maximum input offset and 0.25 µV/°C maximum drift should be included in calibration and error budgets. The bridge excitation amplitude must be selected so the INA131AP output remains inside its output range and does not exceed the available supply headroom.
推薦
Industrial Analog Measurement
The INA131AP supports industrial analog measurement channels that require differential input treatment rather than a simple single-ended amplifier. Its 70 kHz bandwidth is suitable for many process-control and instrumentation signals, while the 0.7 V/µs slew rate provides response for signals within that bandwidth. The ±2.25 V to ±18 V supply range accommodates conventional bipolar analog rails. Because the part has fixed gain of 100, designers should first verify that the sensor output, tolerance, and fault conditions cannot saturate the amplifier. Input filtering and grounding remain essential for reliable industrial measurements.
推薦
Medical Instrument Front End
INA131AP can be evaluated for low-level medical instrumentation when the front end requires differential sensing, a fixed gain of 100, and strong common-mode rejection. The device’s 125 µV maximum input offset becomes 12.5 mV after amplification, making baseline error and calibration important in high-accuracy designs. The 70 kHz bandwidth supports many physiological and diagnostic signals while rejecting higher-frequency noise only when followed by appropriate filtering. Actual suitability depends on leakage, patient-isolation, safety, and application-specific requirements that are not established by the supplied component data and must be reviewed separately.
推薦
Strain and Pressure Measurement
The INA131AP matches strain-gauge and pressure-sensor interfaces that generate small differential outputs across a substantial common-mode voltage. Its gain of 100 avoids an external precision gain network, and 106 dB CMRR helps preserve weak differential information. The fixed gain also makes digital or analog calibration straightforward because every output millivolt corresponds to 10 µV at the input. Engineers must verify bridge excitation, allowable common-mode voltage, sensor output impedance, and saturation margin. Temperature drift of no more than 0.25 µV/°C should be included when defining total measurement accuracy.
推薦
Legacy Laboratory and Data Acquisition
The 8-pin PDIP package makes INA131AP convenient for through-hole laboratory prototypes, educational instrumentation, and legacy data-acquisition boards. Its precision fixed gain of 100 and 70 kHz bandwidth are useful for conditioning low-level differential channels without an adjustable gain network. The package supports conventional PCB assembly and prototype replacement, although it is larger than modern surface-mount alternatives. Engineers should verify the numbered pin assignments in the manufacturer datasheet, use suitable bypass capacitors, and maintain a clean reference and ground arrangement. The verified source does not establish a complete modern lifecycle status for every package variant.
推薦
推薦產品摘要
工程參考資料，適用於 INA131AP — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | INA131AP-1 | INA131BPG4 | LT1012IN8#PBF | AMP04FPZ |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Linear Technology | Analog Devices |
| Package | PDIP-8 | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Amplifier Type | Precision fixed-gain instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier |
主要差異化特點
- Verified precision gain and CMRR combination (對比LT1012IN8#PBF)
- Input overvoltage tolerance (對比AMP04FPZ)
- Same-family 8-pin PDIP sourcing path (對比INA131BPG4)
設計說明
Calculate output swing before finalizing the sensor excitation or shunt current. The INA131AP has fixed gain of 100, so the ideal output is 100 times the differential input; a 10 mV differential signal produces a nominal 1 V output. The supplied operating range is ±2.25 V to ±18 V, but the datasheet output-swing and common-mode limits must also be respected. Use the Texas Instruments INA131 datasheet for input and output limit conditions rather than treating the absolute supply rails as usable signal ranges.
Place input, output, reference, and supply-connection components close to their associated pins and preserve the pin assignments shown in the official manufacturer package drawing. The complete numbered pinout was not reproduced in the verified source data, so the generated record intentionally leaves it null. During layout review, confirm the gain-setting, reference, input, output, and supply pins directly against the TI datasheet. Keep sensitive input traces away from switching nodes and maintain a compact, continuous return path beneath the sensitive analog section.
Include the INA131AP’s gain and offset in the end-to-end error budget. At gain of 100, the verified 125 µV maximum input offset corresponds to 12.5 mV at the output, while the 0.25 µV/°C maximum drift contributes 25 µV/°C referred to the output before other system errors. Input bias current of no more than 2 nA can create an error proportional to source impedance. These figures make source-impedance matching, calibration, and temperature compensation especially important for high-accuracy bridge or shunt measurements.
Do not assume that every 8-pin instrumentation amplifier is automatically interchangeable with the INA131AP. Confirm numbered pin mapping, fixed gain, common-mode range, output swing, supply limits, reference behavior, bandwidth, and input protection before fitting an alternative to an existing PCB. The verified cross-reference material specifically identifies LT1012IN8#PBF and AMP04FPZ as candidates requiring evaluation, while TI discussion highlights distinctions among INA131 orderable suffixes. Use the current manufacturer datasheet and cross-reference records for each candidate rather than relying only on the DIP-8 package.
合規資訊
The supplied verified web data does not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status for INA131AP. Compliance values are therefore left unknown rather than inferred from the manufacturer name or package.