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.