INA122P - 36V Micropower Instrumentation Amplifier | TI
MPN: INA122P ✓ Hoạt độngINA122P Tóm tắt
An instrumentation amplifier is a specialized amplifier category that measures the voltage difference between two input signals while rejecting common-mode noise. INA122P belongs to the broader hierarchy of instrumentation amplifier, differential amplifier, amplifier IC, and analog signal-conditioning IC. This position allows the device to sit between a sensor and an ADC or measurement system, where weak sensor outputs must be amplified without allowing the common-mode voltage to corrupt the result.
Key features include a 60 µA low quiescent current, single-supply operation up to 36 V, dual-supply operation up to ±18 V, a common-mode range extending to V− − 0.1 V, and rail-to-rail output swing. The verified manufacturer data also identifies low offset voltage, low offset drift, and low noise as important characteristics for precision measurements. These features support battery-powered and portable systems where power consumption, input range, and signal fidelity are primary design constraints.
The two-op-amp design provides accurate, low-noise differential acquisition in a single integrated circuit. Unlike a general-purpose op-amp used with a manually matched resistor network, the INA122P integrates the differential signal-conditioning function and is intended for applications such as bridges, load cells, thermocouples, and other low-level transducers. The common-mode and output-swing characteristics allow the amplifier to operate near the lower supply rail, which is useful in single-supply sensor systems.
Typical applications include portable medical monitoring, industrial data acquisition, battery-powered instrumentation, bridge and load-cell signal conditioning, thermocouple interfaces, and low-level sensor measurement. In each case, the device can amplify a differential sensor signal while its low quiescent current helps preserve battery life. Designers should still verify input common-mode limits, output swing, gain configuration, supply range, and external resistor or capacitor requirements against the manufacturer datasheet.
A key design consideration is maintaining adequate supply headroom and correct gain-setting components. Input and output signal ranges must remain within the specified common-mode and swing limits at every temperature and load condition. Place the device close to the sensor source when possible to reduce noise pickup, and follow the manufacturer datasheet for decoupling, gain resistor selection, grounding, and input protection.
This page combines the verified Texas Instruments datasheet information, distributor listing data, and application-oriented engineering guidance for engineers evaluating the INA122P. It also distinguishes exact INA122 family packaging variants from unverified substitutes, helping PCB designers avoid assuming that different packages or amplifier families are drop-in compatible.
Bộ thay thế dễ dàng lắp đặt cho INA122P — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với INA122P (cùng hình factor và footprint) — khác nhau ở Package, Quiescent Current, Architecture, Mounting Type, Supply Voltage Range.
INA122PA
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
INA122U
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →INA122PA
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
INA126PA
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →INA122P Tỷ lệ tối đa & tính chất điện
| Product Type | Precision instrumentation amplifier |
| Architecture | Two-op-amp design |
| Điện áp yên tĩnh | 60 µA |
| Supply Voltage Range | 2.2 V to 36 V |
| Dual-Supply Range | ±18 V |
| Common-Mode Range | V− − 0.1 V |
| Output Swing | Rail-to-rail |
| Low Offset Voltage | 250 µV maximum |
| Low Offset Drift | 3 µV/°C maximum |
| Circuit Count | 1 circuit |
| Hộp | 8-pin plastic DIP (8-PDIP) |
| Kiểu lắp đặt | Through-hole |
| Nhiệt độ hoạt động | −40 °C to +85 °C |
| Application Category | Portable medical and data-acquisition instrumentation |
| Signal Type | Differential |
| Trạng thái RoHS | unknown |
| REACH Status | unknown |
| AEC-Q100 Qualification | unknown |
Cấu hình chân INA122P
| Chân 1 | RG — Gain-setting resistor connection; verify exact function in the manufacturer datasheet |
| Chân 2 | IN− — Inverting differential input |
| Chân 3 | IN+ — Non-inverting differential input |
| Chân 4 | V− — Negative supply or ground in single-supply operation |
| Chân 5 | RG — Gain-setting resistor connection; verify exact function in the manufacturer datasheet |
| Chân 6 | OUT — Amplified differential output |
| Chân 7 | VS — Positive supply |
| Chân 8 | REF — Reference input for output-voltage operation; verify exact function in the manufacturer datasheet |
Ứng dụng tiêu biểu
INA122P phù hợp cho 6 Áp dụngs: Portable Medical Instrumentation, Load-Cell Signal Conditioning, Battery-Powered Data Acquisition, Thermocouple and Low-Level Sensor Interface, Bridge-Sensor Measurement, Industrial Sensor Interface.
Portable Medical Instrumentation
INA122P fits portable medical measurement systems that must acquire weak differential sensor signals while keeping power consumption low. Its verified 60 µA quiescent current is valuable when the instrument operates from a battery, and the 2.2 V to 36 V supply range allows integration across different portable-system rails. The amplifier can condition pressure, temperature, or other transducer outputs before an ADC. Designers should verify common-mode voltage, output swing, isolation requirements, and medical-product validation procedures.
Được đề xuất
Load-Cell Signal Conditioning
INA122P is suited to load-cell and strain-gauge front ends that produce small differential signals in the presence of larger common-mode voltages. Its instrumentation-amplifier architecture is intended for accurate differential acquisition, while the 60 µA quiescent current supports low-power portable weighing systems. Use the device ahead of an ADC or measurement converter and confirm excitation voltage, input common-mode limits, gain setting, and output range. PCB layout should keep sensor traces short and away from switching circuitry.
Được đề xuất
Battery-Powered Data Acquisition
The INA122P supports compact data-acquisition systems where every milliamp of supply current can affect battery life. Its 60 µA quiescent current helps the analog front end operate continuously, and its supply range from 2.2 V to 36 V provides flexibility for single-supply and higher-voltage arrangements. The device can amplify sensor differences before conversion or transmission. Confirm actual power consumption across operating mode, sensor impedance, gain components, and downstream circuitry, and validate common-mode range for every input condition.
Được đề xuất
Thermocouple and Low-Level Sensor Interface
INA122P can serve as the differential input stage for thermocouples and other low-level sensors whose useful signal is much smaller than the surrounding common-mode voltage. Its low offset voltage, low offset drift, and low-noise positioning are important when preserving small sensor variations. The amplifier’s verified common-mode limit and rail-to-rail output swing determine how closely the sensor may operate to the supply rails. Use appropriate input protection, cold-junction compensation where required, and grounding techniques designed for the thermocouple itself.
Được đề xuất
Bridge-Sensor Measurement
The INA122P is appropriate for resistive bridge sensors where the measurement depends on a small differential voltage generated by a change in resistance or pressure. Its instrumentation-amplifier function rejects common-mode excitation and provides a clean differential input stage for downstream conversion. The device’s 2.2 V to 36 V supply capability supports flexible bridge excitation architectures. Confirm the bridge excitation voltage, sensor output range, gain network, input protection, and ADC input range before production release.
Được đề xuất
Industrial Sensor Interface
INA122P can be used in industrial sensor interfaces when low power, differential measurement, and flexible supply operation are important. Its 60 µA quiescent current is useful for remote or portable instrumentation, while the wide supply range supports both compact low-voltage systems and higher-voltage industrial front ends. The common-mode specification must be checked against the sensor and excitation circuit, particularly when long cables or grounding differences are present. Add filtering and protection as required by the application environment.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho INA122P — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | INA122PA | INA122U | INA126PA |
|---|---|---|---|---|
| Package | 8-PDIP | 8-PDIP | 8-PDIP | 8-PDIP |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Product Type | Precision instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier |
Bảo phân biệt quan trọng
- Very low micropower consumption (vsINA126PA)
- Wide single-supply operating range (vsINA122PA)
- Single or dual supply flexibility (vsINA122U)
- Precision offset characteristics (vsINA126PA)
- Portable-instrumentation positioning (vsINA122PA)
Ghi chú thiết kế
Use the verified 60 µA quiescent current as the baseline for battery and portable-instrumentation power budgeting, but include the current consumed by the gain-setting network, sensor, ADC, and external protection. Because INA122P accepts a 2.2 V to 36 V supply range, confirm the actual rail voltage against the sensor common-mode requirement and the required output headroom. Estimated: the amplifier’s own quiescent contribution at 3.3 V is 0.198 mW, calculated as 3.3 V × 60 µA; this excludes all other circuit loads.
Place the INA122P close to the sensor input connector and keep the differential input traces short, matched where practical, and away from switching nodes and high-current return paths. Use a quiet ground reference and follow the manufacturer datasheet for decoupling and gain-component placement. A long cable or improperly grounded sensor can introduce noise that no amount of downstream digital filtering can fully recover.
Do not assume that the output can swing exactly to either supply rail under every load, temperature, or supply condition. Although the verified data describes rail-to-rail output swing, check the manufacturer operating conditions and leave the required output margin for the ADC input range. Also verify the input common-mode voltage against the specified V− − 0.1 V limit before connecting a sensor.
Treat the reference and gain-setting network as part of the precision signal path. Keep those components physically close to the appropriate INA122P pins, use stable ground references, and avoid routing high-current or digital return paths beneath differential inputs. If the sensor is remote, add appropriately selected input protection and filtering and validate the complete board for temperature drift and common-mode transients.
Thông tin tuân thủ
The supplied verified data does not state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. These fields remain unknown rather than assumed.
