The TC7129 is a 4-1/2 digit Analog-to-Digital Converter （ADC） that directly drives a multiplexed Liquid Crystal Display （LCD）。 Fabricated in high-performance， lowpower CMOS， the TC7129 ADC is designed specifically for high-resolution， battery-powered digital multimeter applications. The traditional dual-slope method of A/D conversion has been enhanced with a successive integration technique to produce readings accurate to better than 0.005% of full-scale and resolution down to 10 ?V per count. The TC7129 includes features important to multimeter applications. It detects and indicates low battery condition. A continuity output drives an annunciator on the display and can be used with an external driver to sound an audible alarm. Overrange and underrange outputs， along with a range-change input， provide the ability to create auto-ranging instruments. For snapshot readings， the TC7129 includes a latch-and-hold input to freeze the present reading. This combination of features makes the TC7129 the ideal choice for full-featured multimeter and digital measurement applications.