TPS2661 Universal 4 mA to 20 mA Current Loop Protector

Texas Instruments' TPS2661 is a compact, feature-rich, fully-integrated current loop protector suitable for analog inputs, analog outputs, sensor transmitters, HART inputs, and UART IO protection. This protector provides universal input protection for ±20 mA, 0 mA to 20 mA, and 4 mA to 20 mA. A low R_ON of 7.5 Ω minimizes the drop in the current loop extending the operating range and supporting operation even with lower voltage power supplies. The device can withstand and protect the loads from positive and negative supply voltages up to ±50 V. The MODE pin allows flexibility to enable a 2x current limit through the device to enable proper startup of two wire transmitters.

The protector device is capable of operating from an external bipolar supply of ± 2.25 V to ±20 V. It can be powered from unipolar supplies of 3 V to 30 V. The TPS26610 device features a loop power mode to facilitate loop testing in an un-powered state without ±Vs supplies. The device protects the system from output side miswiring in analog outputs and sensor transmitters by turning off the current path. The internal robust protection control blocks and the 50 V rating helps to protect against surge (IEC61000-4-5) and EFT (IEC61000-4-4) transients for the signal lines. The device greatly reduces system footprint by its 2.9 mm x 1.6 mm, 8-pin SOT-23 package.