Instrumentation Operational Amplifier Texas Instruments INA111AP PDIP-8

The Texas Instruments INA111AP in a PDIP-8 package is an instrumentation operational amplifier designed for precision differential signal amplification. This linear IC provides low offset and low drift performance characteristic of the INA111 family, making it suitable for reliable measurement and signal conditioning in applications that require accurate amplification of small differential voltages. The compact PDIP-8 form factor simplifies through-hole PCB assembly and prototyping while providing the functionality expected from an instrumentation amplifier.

Advantages

The INA111AP offers low input offset and low temperature drift, ensuring stable gain over a wide temperature range. Its instrumentation amplifier topology provides high common-mode rejection, which reduces the influence of noise and interference on differential measurements. The device supports single-supply or dual-supply operation and provides predictable gain when configured with an external resistor, enabling flexible integration into measurement front-ends and sensor interfaces.

Suitable for

• Sensor signal conditioning (strain gauges, thermocouples, bridge transducers)
• Data acquisition front-ends and ADC driver stages
• Medical instrumentation and physiological signal amplification
• Laboratory measurement circuits and precision test equipment

Key specifications

• Instrumentation amplifier architecture for differential input signals
• Low input offset voltage and low offset drift with temperature
• High common-mode rejection ratio to minimize interference
• Gain set by an external resistor for flexible amplification
• PDIP-8 through-hole package for easy prototyping and PCB mounting
• Support for single-supply or dual-supply operation depending on circuit design

How to use

Install the INA111AP into a PDIP-8 socket or solder it to a through-hole PCB following standard handling and anti-static precautions. Configure the amplifier by selecting an appropriate external resistor between the designated pins to set the required gain according to the manufacturer’s gain equation. Provide appropriate supply rails (single or dual) and decoupling capacitors near the supply pins to ensure stable operation. Route input traces carefully and, where possible, use differential routing or guarding to minimize noise pickup and offset errors.

Recommendations

For optimal measurement accuracy, use low-noise external resistors to set gain, place bypass capacitors close to the supply pins, and maintain short, symmetric input traces. Verify common-mode voltage limits and headroom for the chosen supply configuration to avoid output saturation when amplifying small differential signals.