Analog current/voltage output driver for cost-sensitive process control applications

The XTR305, from Texas Instruments, is a complete output driver for cost-sensitive process and industrial control applications. The output can be configured as voltage or current by the digital I/V select pin. No external shunt resistor is required. Only external gain-setting resistors and a loop compensation capacitor are needed. The separate driver and receiver channels provide flexibility. The instrumentation amplifier (IA) can be used for remote voltage sense or as a high-voltage, high-impedance measurement channel. In voltage-output mode, a copy of the output current is provided, allowing calculation of load resistance. The digital output-selection capability, together with the error flags and monitor pins, makes troubleshooting and remote configuration possible. Fault conditions on the output and on the IA input, as well as overtemperature conditions, are shown by the error flags. The monitoring pins offer continuous feedback about impedance or load power. For further protection, the maximum output current is limited, and thermal protection is provided. The device is specified over the -40C to +85C industrial temperature range and for supply voltages up to 40V, and is operational over the extended industrial temperature range (-55C to +125C).