INA121U/2K5 – TEXAS INSTRUMENTS

The Texas Instruments INA121U/2K5 is a precision, low-power, instrumentation amplifier specifically designed for applications requiring high common-mode rejection ratio (CMRR) and low input bias current. The “/2K5” suffix denotes a gain of 2.5, fixed internally. This eliminates the need for external gain-setting resistors, simplifying design and reducing component count. The device operates from a ±15V to ±18V supply voltage range, consuming a typical supply current of only 300µA. Packaged in a small 8-pin SOIC package, it boasts a typical input offset voltage of only 25µV, ensuring high accuracy in signal amplification. Its high CMRR, typically 100dB at 60Hz, makes it ideal for rejecting common-mode noise in applications like sensor signal conditioning, where precise measurement amidst noisy environments is crucial. The INA121U/2K5’s low input bias current (typically 25nA) minimizes errors caused by high-impedance sources. Its advantages include reduced design complexity, enhanced accuracy, and minimized power consumption, making it a cost-effective solution for applications requiring a fixed gain of 2.5 with high precision. Avoid using this part where a variable gain is required or if the supply voltage exceeds the specified range.