INA157U - 3MHz Precision Difference Amplifier | Texas Instruments
MPN： INA157U ✓ 啟用中INA157U 概覽
A difference amplifier is a specialized amplifier IC that measures the voltage between two input terminals while rejecting signals common to both inputs. Positioned within the hierarchy of difference amplifier, instrumentation amplifier, operational amplifier, and analog signal-conditioning IC, it is used where accurate subtraction, current-sense measurement, or rejection of common-mode interference is required.
The INA157U integrates a precision operational amplifier with a laser-trimmed resistor network. According to the Texas Instruments manufacturer datasheet, the internal resistors are ratio matched, although their absolute values may vary by ±20%. This ratio matching supports accurate gain and common-mode rejection. The listed low offset voltage, low thermal drift, low gain error, and 3 MHz bandwidth make the device useful where both dc accuracy and signal bandwidth matter.
Typical applications include differential voltage measurement, current-shunt amplification, industrial sensor interfaces, bridge-sensor signal conditioning, and communication-circuit gain stages. A compact SOIC package supports conventional surface-mount assembly, while the extended industrial temperature range supports equipment operating across temperature extremes. The 3 MHz bandwidth also allows the amplifier to process signals beyond low-frequency precision-only applications.
Designers should preserve adequate input and output voltage headroom, verify common-mode and output-swing limits against their actual signal, and route sensitive differential inputs using short, symmetric paths. Because the internal resistor network contributes noise and absolute resistance tolerance, board-level calibration should use ratio accuracy rather than assuming a nominal resistor value.
This page combines the verified manufacturer specifications, distributor availability references, practical application guidance, and drop-in comparison information for engineers evaluating the INA157U.
直接替換替代品，適用於 INA157U — 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。
此系列的變體
與下列產品可直接替換的同系列型號： INA157U （相同外形與佔位） — 差異在於 Package, Bandwidth, Internal Resistor Network, Operating Temperature Range.
INA157UG4
✅ 直接替換📋 參考替代品（不在目錄中）
INA157U 最大額定值與電氣特性
| Product Type | High-speed, precision difference amplifier |
| Bandwidth | 3 MHz |
| Maximum Offset Voltage | ±500 µV |
| Maximum Offset Drift | ±2 µV/°C |
| Maximum Gain Error | ±0.05% |
| Circuit Count | 1 circuit |
| 工作溫度範圍 | -40°C to +85°C |
| 封裝 | 8-pin SOIC |
| 安裝類型 | Surface mount |
| Internal Resistor Network | Precision, ratio-matched, laser-trimmed |
| Internal Resistor Absolute Tolerance | ±20% |
| RoHS 狀態 | unknown |
INA157U 8-pin soic 腳位配置指南
INA157U（8-pin soic 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： INA157U.
請參閱 資料表 以查看完整腳位配置。
典型應用
INA157U 適用於 6 應用s: High-Side Current Sensing, Industrial Sensor Interfacing, Bridge-Sensor Measurement, Communication Receiver Front End, Precision Difference Measurement, Data Acquisition Analog Front End.
High-Side Current Sensing
The INA157U fits current-sense signal conditioning when a shunt voltage must be measured while a larger common-mode voltage is present. Its difference-amplifier topology avoids constructing a separate precision resistor network, and the verified 3 MHz bandwidth provides useful response beyond dc. The designer must still confirm the INA157U common-mode range, supply voltage, output swing, and gain configuration against the shunt and load. Short, matched input traces help preserve differential behavior and reduce conversion of common-mode noise into differential error.
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Industrial Sensor Interfacing
The INA157U is appropriate for conditioning differential outputs from industrial sensors, where sensor signals may be small and referenced away from ground. Its verified maximum offset voltage of ±500 µV and maximum gain error of ±0.05% provide useful precision figures for signal-chain budgets. The 3 MHz bandwidth can accommodate dynamic sensor outputs while the extended -40°C to +85°C specification supports industrial environments. Confirm supply and common-mode limits before selecting it for a particular bridge, transducer, or remote sensor.
推薦
Bridge-Sensor Measurement
The INA157U can amplify the differential voltage generated by resistive bridge sensors while rejecting a common excitation voltage. Its integrated ratio-matched resistor network supports consistent differential gain, while the verified ±2 µV/°C maximum offset-drift specification helps with temperature-sensitive measurements. The device's 3 MHz bandwidth is more than sufficient for many static or slowly varying bridge signals, although actual noise and settling behavior must be checked in the complete circuit. Validate excitation polarity, input range, and output saturation.
推薦
Communication Receiver Front End
The INA157U may be used in a communication receiver front end when a differential signal requires local gain before conversion or filtering. The verified 3 MHz bandwidth provides a concrete upper frequency figure for design partitioning, while the precision resistor network reduces the need for a discrete matched gain stage. In practice, common-mode voltage, output headroom, noise, stability, and impedance matching must be evaluated against the receiver architecture. The component is best suited to analog stages where its 3 MHz bandwidth and low-offset characteristics match the signal path.
推薦
Precision Difference Measurement
The INA157U is well suited to precision differential measurements where two voltages must be subtracted and the result is presented as a single-ended analog signal. The verified ±500 µV maximum offset voltage, ±0.05% maximum gain error, and integrated resistor network simplify error budgeting compared with a discrete implementation. Its -40°C to +85°C operating range supports a broad range of equipment. Use careful input routing and verify the output range so the measured difference does not drive the amplifier outside its linear operating region.
推薦
Data Acquisition Analog Front End
The INA157U can provide differential amplification ahead of an ADC in a data-acquisition system when the source has balanced or common-mode-rejected signaling. Its 3 MHz bandwidth gives designers a defined signal-rate target, while the offset and gain-error figures help establish an initial precision budget. The SOIC package is straightforward to route on a conventional mixed-signal board, but the selected ADC, input range, sampling architecture, and isolation requirements determine whether INA157U is the best amplifier. Verify settling and output drive against the ADC input.
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推薦產品摘要
工程參考資料，適用於 INA157U — 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 | INA157UG4 | INA157UA | INA141UA |
|---|---|---|---|---|
| Package | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | SOP-8 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
主要差異化特點
- Integrated precision difference-amplifier function (對比INA141UA)
- Verified precision figures (對比INA141UA)
- High-speed versus low-power positioning (對比INA141UA)
設計說明
Route the two differential inputs as short, closely spaced traces with matched geometry. Keep the amplifier input nodes away from switching-node copper and high-current return paths. Because the INA157U uses a precision difference stage, unequal trace impedance or asymmetric grounding can convert common-mode energy into differential error. Check the completed PCB for input capacitance and verify settling at the intended signal rate.
Confirm supply voltage, input common-mode range, and output-swing limits from the manufacturer datasheet before applying signals. The verified data identifies the 3 MHz bandwidth but does not provide complete electrical limits. Place the required bypass capacitors close to the supply pins, maintain a low-impedance return path, and verify startup and shutdown behavior if the source can be disconnected while the amplifier remains powered.
Do not assume the internal resistor network has exact nominal resistance. Texas Instruments states that the internal resistors are ratio matched but may have ±20% absolute tolerance. This favors ratio accuracy but does not justify using a nominal resistor value for absolute gain calculations. For systems needing calibrated accuracy, include gain calibration or calibration in the downstream measurement chain and account for resistor noise.
合規資訊
The verified search results identify Texas Instruments and the INA157 family but do not provide RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. No compliance status is inferred.