Overview
The INA117P, produced by Texas Instruments, is a precision unity-gain difference amplifier designed to accurately measure small differential voltages in the presence of high common-mode signals. This single monolithic IC integrates a precision op amp and a thin-film resistor network, enabling it to handle common-mode input voltages up to ±200V. The device is particularly useful in applications where galvanic isolation is not essential, allowing it to replace isolation amplifiers and eliminate the need for costly isolated power supplies. The INA117P is available in 8-pin plastic mini-DIP and SO-8 surface-mount packages, with an operating temperature range of –40°C to 85°C.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Common-mode input range | ±200V (VS = ±15V) | V |
| Protected inputs (Common-mode/Differential) | ±500V | V |
| Unity gain error | 0.05% maximum | % |
| Nonlinearity | 0.001% maximum | % |
| CMRR (Common-mode rejection ratio) | 70dB minimum | dB |
| Bandwidth, –3dB | 200kHz | kHz |
| Slew rate | 1.7 to 2.6 V/μs | V/μs |
| Output impedance | 0.01 Ω | Ω |
| Quiescent current | 1.5 ± 2 mA | mA |
| Operating temperature range | –40°C to 85°C | °C |
| Package types | 8-pin PDIP, 8-pin SOIC |
Key Features
- High common-mode input voltage range up to ±200V
- Protected inputs against momentary common-mode or differential overloads up to ±500V
- Unity gain with a maximum error of 0.05%
- Low nonlinearity of 0.001% maximum
- High CMRR of 70dB minimum
- Bandwidth of 200kHz and slew rate of 1.7 to 2.6 V/μs
- Low output impedance of 0.01 Ω
- Compact 8-pin packaging in both DIP and SOIC formats
Applications
- Single multi-axis servo drives
- Industrial machines and machine tools
- Semiconductor test and Automated Test Equipment (ATE)
- Ultrasound scanners
- Current sensing and measurement in various industrial and medical devices
Q & A
- What is the common-mode input voltage range of the INA117P?
The INA117P can handle common-mode input voltages up to ±200V (VS = ±15V).
- What is the maximum gain error of the INA117P?
The maximum gain error is 0.05%.
- What is the nonlinearity of the INA117P?
The nonlinearity is 0.001% maximum.
- What is the CMRR of the INA117P?
The CMRR is 70dB minimum.
- What are the package options for the INA117P?
The INA117P is available in 8-pin plastic mini-DIP and SO-8 surface-mount packages.
- What is the operating temperature range of the INA117P?
The operating temperature range is –40°C to 85°C.
- Can the INA117P replace isolation amplifiers in some applications?
- How does the INA117P handle noise performance?
The noise performance is dominated by the internal resistor network, with approximately 550nV/√Hz noise. Noise can be reduced with a low-pass filter on the output.
- What are some common applications of the INA117P?
- How can the INA117P be used for current measurement?
