Op Amp enables High-Accuracy Current Sensing

The TSX712 dual, operational amplifier (op amp) from STMicroielectronics offers high precision functioning with low input offset voltage down to a maximum of 200 µV at 25 degrees C. In addition, its rail-to-rail input and output functionality allows this product to be used on full range input and output without limitation.

This is particularly useful for a low-voltage supply such as 2.7V that the TSX712 is able to operate with. Thus, the TSX712 has the great advantage of offering a large span of supply voltages, ranging from 2.7V to 16V. It can be used in multiple applications with a unique reference.

Low input bias current performance makes the TSX712 well-suited when used for signal conditioning in sensor interface applications. In addition, low-side and high-side current measurements can be easily made thanks to rail-to-rail functionality.

Low-side current sensing provides the benefits of reduced cost and simplified designs. Using a high-performance op amp such as the TSX712 enables the use of a lower-value shunt resistor, reducing loses, lower costs but lower accuracy. The TSX712 provides an excellent input offset value (VIO) combined with a large enough gain-bandwidth product (GBP) and slew rate to enable a high-efficiency, high-performance current sensing solution.

Key features of the TSX712 include: Low input offset voltage of 200µV max.; Rail-to-rail input and output; Low current consumption of 800µA max.; Gain bandwidth product of 2.7MHz; Low supply voltage from 2.7- to 16-V; Unity gain stable; Low input bias current of 50pA max.; ESD tolerance of 4kV HBM; Extended temp. range from -40 to +125 degrees C; and automotive qualification.