INA155U - 5.5V 550kHz CMOS INA | Texas Instruments
MPN： INA155U ✓ 啟用中INA155U 概覽
An instrumentation amplifier is a specialized analog IC that amplifies the difference between two input signals while rejecting common-mode noise. INA155U belongs to the broader hierarchy of analog signal-conditioning devices: instrumentation amplifier, differential amplifier, analog amplifier, and semiconductor. This device is particularly useful when a sensor output is small, noisy, or referenced to a changing common-mode voltage and the next stage requires a larger single-ended signal.
The manufacturer identifies the INA155 family as a 5.5 V single-supply, 550 kHz, rail-to-rail-output CMOS instrumentation amplifier. The verified distributor data identifies INA155U as a one-circuit, rail-to-rail-output device in an 8-pin SOIC package. The 550 kHz bandwidth makes it appropriate for signal paths that require response beyond static precision measurements, provided the application does not require high-frequency instrumentation-amplifier performance.
The INA155U is intended for low-voltage sensor interfaces, portable measurement systems, industrial signal conditioning, and analog-to-digital converter front ends. Its rail-to-rail output can simplify designs using a 3.3 V or 5 V supply because the output can swing close to the upper rail under suitable load conditions. The exact input common-mode range, gain settings, output swing, noise, and current specifications were not included in the verified data and must be checked in the manufacturer datasheet before final design release.
For PCB implementation, use a low-noise ground reference, place input and feedback components close to the device, and keep sensitive differential traces short and symmetric. Decoupling capacitors should be placed at the supply pins according to the manufacturer recommendations. Verify the complete signal chain against the datasheet limits, especially when the source impedance, gain, output load, supply voltage, or common-mode input level differs from the nominal application conditions.
This page combines the verified INA155U product identity and distributor links with structured application, comparison, and design guidance. It does not infer electrical values that were not explicitly supplied in the retrieved data, and it identifies missing parameters for engineering confirmation.
直接替換替代品，適用於 INA155U — 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： INA155U （相同外形與佔位） — 差異在於 Product Type, Bandwidth, Input Offset Voltage, Slew Rate.
INA155UA
✅ 直接替換聯絡詢價
查看資料表 →INA155UG4
✅ 直接替換📋 參考替代品（不在目錄中）
INA155U/2K5
✅ 直接替換📋 參考替代品（不在目錄中）
INA141UA/2K5E4
✅ 直接替換📋 參考替代品（不在目錄中）
INA154U
✅ 直接替換聯絡詢價
查看資料表 →INA155E/250
✅ 直接替換📋 參考替代品（不在目錄中）
INA155U 最大額定值與電氣特性
| Product Type | CMOS instrumentation amplifier |
| Number of Channels | 1 circuit |
| 供應電壓 | 5.5 V maximum single supply |
| Supply Topology | Single supply |
| Bandwidth | 550 kHz |
| Output Offset Voltage | 1 mV |
| 輸出類型 | Rail-to-rail output |
| Input Type | Differential instrumentation-amplifier input |
| Technology | CMOS |
| 封裝 | 8-pin SOIC |
| 安裝類型 | Surface mount |
INA155U 8-pin soic 腳位配置指南
INA155U（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： INA155U.
請參閱 資料表 以查看完整腳位配置。
典型應用
INA155U 適用於 6 應用s: Low-Voltage Sensor Signal Conditioning, Portable Battery-Powered Measurement, ADC Input Amplification, Industrial Process Monitoring, Bridge and Strain-Sensor Interfaces, Precision Analog Signal Conditioning.
Low-Voltage Sensor Signal Conditioning
The INA155U fits low-voltage differential sensor front ends where the sensor produces a small signal referenced to a changing common-mode voltage. Place the two sensor outputs on the differential inputs, configure the gain according to the manufacturer’s supported resistor or internal-gain arrangement, and use the rail-to-rail output to preserve signal swing toward the positive supply. The verified 550 kHz bandwidth supports moderate-speed conditioning, while the 1 mV offset specification is relevant when the sensed quantity is small. Confirm input common-mode limits, source impedance, gain accuracy, and output loading before production release.
推薦
Portable Battery-Powered Measurement
The single-supply INA155U is appropriate for portable measurement systems operated from a low-voltage battery or regulated rail. Its verified 5.5 V maximum single-supply description supports compact analog front ends, and the CMOS implementation is suitable for power-conscious instrumentation. The rail-to-rail output can help retain usable dynamic range when the amplifier is powered from a 3.3 V or 5 V system, subject to the exact output-swing and load limits. Validate battery maximum, startup behavior, supply current, and common-mode headroom in the manufacturer datasheet.
推薦
ADC Input Amplification
The INA155U can condition a differential sensor or transducer signal before conversion by an ADC. The 550 kHz verified bandwidth provides response for many moderate-speed acquisition paths, while the instrumentation-amplifier architecture helps reject common-mode disturbance before digitization. Use the output to drive the ADC within its input range, adding an anti-alias filter when required by the signal bandwidth and sampling rate. Because ADC drive current, acquisition time, and the INA155U settling specifications were not included in the verified data, those values must be checked together before selecting the gain.
推薦
Industrial Process Monitoring
The INA155U can amplify low-level differential process signals in industrial monitoring equipment when the supply and common-mode requirements match its operating limits. Differential inputs help reduce sensitivity to shared supply and ground disturbances compared with a single-ended amplifier, while the 550 kHz bandwidth accommodates many sensor signals that do not require wide-band instrumentation-amplifier performance. Provide local supply decoupling, a quiet analog ground, and input protection appropriate to the transducer. Verify the complete industrial temperature, isolation, surge, and EMC requirements separately.
推薦
Bridge and Strain-Sensor Interfaces
The INA155U is a candidate for bridge or strain-sensor interfaces that generate a small differential voltage around a common-mode level. The instrumentation-amplifier topology is intended to amplify that differential result and suppress common-mode error, which is useful when the sensor output is small and the surrounding analog node is electrically noisy. Gain, input bias behavior, excitation settling, and allowable sensor impedance must be confirmed from the manufacturer datasheet. Add input filtering and ESD protection only after checking their capacitance, leakage, and noise effects on the measurement bandwidth.
推薦
Precision Analog Signal Conditioning
The INA155U can serve as a precision analog signal-conditioning stage when a differential source requires amplification before comparison, measurement, or further filtering. The verified 1 mV offset specification provides a concrete starting point for offset-error analysis, while rail-to-rail output increases available signal range near the upper supply limit. The 550 kHz bandwidth should be compared with the required settling time and noise bandwidth rather than treated as an all-purpose frequency limit. Confirm resistor values, gain accuracy, output load, and temperature drift before using it in a precision measurement chain.
推薦
工程參考資料，適用於 INA155U — 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 | INA155UA | INA155UG4 | INA155U/2K5 | INA141UA/2K5E4 |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC |
| Product Type | CMOS instrumentation amplifier | Instrumentation amplifier | CMOS instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier |
| Number of Channels | 1 circuit | 1 channel | 1 channel | 1 channel | 1 channel |
| Output Architecture | Rail-to-rail output | Rail-to-rail output | Rail-to-rail output | Rail-to-rail output | Rail-to-rail output |
主要差異化特點
- Single-supply rail-to-rail-output architecture (對比INA141UA/2K5E4)
- Verified 550 kHz bandwidth (對比INA155UA)
- 1 mV offset specification (對比INA154U)
設計說明
Keep the two differential input traces short, matched in length, and surrounded by a continuous ground reference where practical. Route feedback and gain-setting components close to the relevant device pins, and avoid sharing high-current return paths with the input reference. The verified data confirms a differential CMOS instrumentation amplifier but does not provide the exact pin names or recommended layout, so consult the official package drawing and datasheet before final routing.
Place the required supply-decoupling capacitors immediately at the device supply and ground pins, and keep the analog supply path separate from switching-node and motor-return currents wherever possible. The verified 5.5 V maximum single-supply specification must not be treated as a recommended operating point; check absolute maximum and recommended supply limits. Also verify output loading and rail-to-rail behavior under the actual load rather than assuming full rail swing.
Treat the sensor source impedance, differential input capacitance, and feedback network as a matched system. Excess source imbalance can degrade common-mode rejection, while long or asymmetric traces can add phase delay and reduce the effective bandwidth below the verified 550 kHz family specification. Add filtering only after calculating its effect on settling and signal bandwidth, and validate the complete channel with the intended sensor and ADC or downstream load.
合規資訊
The supplied verified data confirms the manufacturer, product type, package, supply class, bandwidth, offset, and distributor listings, but does not provide explicit RoHS, REACH, lead-free, halogen-free, conflict-minerals, or automotive qualification statements.