Instrumentation Operational Amplifier Texas Instruments INA128PA, Precision INA128PA, PDIP-8

The Texas Instruments INA128PA is a precision instrumentation operational amplifier in a PDIP-8 package designed for accurate differential signal amplification and low‑drift performance. It offers stable gain, low offset voltage and low input bias currents, making it suitable for sensor signal conditioning, bridge amplifier applications and data acquisition front-ends where precise measurement and signal integrity are required.

Advantages

The INA128PA provides precision differential amplification with low offset and drift, enabling consistent performance over temperature. Its low input bias current preserves accuracy when used with high-impedance sensors or bridge configurations. The device’s packaging and pinout simplify prototyping and through‑hole mounting, while its internal design supports stable gain settings and low noise for measurement applications.

Suitable for

• Amplification of bridge sensors (strain gauges, load cells)
• Medical instrumentation input stages requiring low offset
• Precision measurement and data acquisition front-end circuits
• Signal conditioning for thermocouples and RTDs with appropriate frontend
• Laboratory prototypes and educational electronics using PDIP packages

Key specifications

• Amplifier type: instrumentation/operational amplifier with differential inputs
• Package: 8‑pin PDIP (through‑hole)
• Low input offset voltage and low offset drift suitable for precision applications
• Low input bias current for use with high‑impedance sources
• Stable gain characteristics for accurate differential amplification
• Low noise optimized for measurement and sensor conditioning

How to use

Install the INA128PA in the PDIP‑8 socket or solder it to a through‑hole PCB according to the standard pinout for instrumentation amplifiers. Configure gain using external resistors between the gain pins as specified in the device documentation; small changes to resistor values set the required differential gain. Provide appropriate power supply voltages and bypass capacitors close to the supply pins to ensure stability and low noise. Connect sensor or bridge outputs to the differential input pins and route the amplified output to the next stage of the measurement system or ADC input.

Recommendations

Use short, low‑impedance traces for input connections and place supply decoupling capacitors near the device. Match source impedances where possible and include input filtering if the environment contains significant electromagnetic interference. For highest precision, allow the amplifier to stabilize thermally and select precision external resistors for gain setting.