INA131BP

Overview

The INA131BP is a precision instrumentation amplifier from Texas Instruments featuring a fixed gain of 100 V/V. It utilizes a three-op amp architecture to deliver high accuracy and low cost. The device operates on dual supplies ranging from 2.25V to 18V per rail, with a maximum supply voltage of 50V. Key electrical characteristics include a maximum input offset voltage of 50µV and a bandwidth of 70kHz. It is housed in an 8-pin PDIP package.

Feature Summary

• Fixed unity-gain-like performance with a precise internal gain of 100 V/V
• Three operational amplifier topology ensures high common-mode rejection
• Low input offset voltage for enhanced measurement accuracy
• Wide single or dual power supply operation capability

Applications

• Precision industrial process control systems
• Medical instrumentation signal conditioning
• Strain gauge and load cell interfaces
• Thermocouple amplification circuits

Procurement Notes

Verify the package type matches your PCB footprint requirements, as this component uses an 8-pin PDIP housing. Confirm that the fixed gain of 100 V/V aligns with your system's signal chain design, as external feedback resistors are not required. Ensure supply voltages remain within the specified 2.25V to 18V range per rail to prevent device damage. Check for RoHS compliance status if environmental regulations apply to your manufacturing process.

Selection Notes

Select this component when a stable, factory-calibrated gain of 100 is required without external resistor tolerance errors. It is suitable for applications demanding high common-mode rejection ratio (CMRR) and low drift. Consider alternative models if adjustable gain or higher bandwidth is necessary, as this part is optimized for precision DC and low-frequency AC signals rather than high-speed data acquisition.

Part Context

The INA131 belongs to Texas Instruments' family of general-purpose instrumentation amplifiers. Unlike programmable gain amplifiers, it offers a permanent internal gain setting, simplifying circuit design by eliminating external gain-setting components. This reduces board space and potential error sources associated with resistor matching, making it ideal for cost-sensitive, high-volume production environments.

Replacement Considerations

Direct substitutes may include other TI instrumentation amplifiers with similar gain specifications, such as the INA131AP. Verify pin compatibility and package dimensions before substitution. Ensure that the replacement maintains the required 70kHz bandwidth and 50µV offset voltage limits for your specific application.