DAC1243 Datasheet | National Semiconductor

Description Features PRELIMINARY The DAC1242/1243 are 12-bit digital-to-analog converters with 4-20m A current loop output. The DAC1242 is a current-sinking device, while the DAC1243 provides true current sourcing into a ground referenced load. The digital input registers are similar to an INS8255, allowing direct TTL interfacing to a variety of 8-bit microprocessors (8080, 8085, 8048, 8070, 8073, NSC800, Z80, et al). Interfacing to other microprocessor families or larger puters requires only 1 or 2 TTL packages. The device occupies 4 contiguous bytes of I/O or address space. The converters produce a 4-20m A output current proportional to the digital input word with 12-bit resolution, guaranteed monotonicity, and <1/2 LSB non- linearity; a 10-bit guaranteed part is also available. Null and span are internally calibrated to allow use of an external 100Q, 1% current-sensing resistor...