description

The HT7135A and TLC7135A converters are manufactured with Htcsemi Instruments highly efficient

CMOS technology. These 4 1/2-digit, dual-slope-integrating, analog-to-digital converters (DACs) are

designed to provide interfaces to both a microprocessor and a visual display. The digit-drive outputs D1

through D4 and multiplexed binary-coded-decimal outputs B1, B2, B4, and B8 provide an interface

for LED or LCD decoder/drivers as well as microprocessors.

The HT7135A and TLC7135A offer 50-ppm (one part in 20,000) resolution with a maximum linearity error of

one count. The zero error is less than 10 µV and zero drift is less than 0.5 µV/°C. Source-impedance errors are

minimized by low input current (less than 10 pA). Rollover error is limited to ±1 count.

The BUSY, STROBE, RUN/HOLD, OVER RANGE, and UNDER RANGE control signals support

microprocessor-based measurement systems. The control signals also can support remote data acquisition

systems with data transfer through universal asynchronous receiver transmitters (UARTs).

The HT7135A and TLC7135A are characterized for operation from 0°C to 70°C.