General Description:

The TC7126A is a 3-1/2 digit CMOS Analog-to-Digital Converter (ADC) containing all the active components necessary to construct a 0.05% resolution measure ment system. Seven-segment decoders, digit and polarity drivers, voltage reference, and clock circuit are integrated on-chip. The TC7126A directly drives a Liquid Crystal Display (LCD), and includes a backplane driver.

A low-cost, high resolution indicating meter requires only a display, four resistors, and four capacitors. The TC7126A’s extremely low-power drain and 9V battery operation make it ideal for portable applications.

Features:

• Internal Reference with Low Temperature Drift:

  - TC7126: 80ppm/°C, Typical

  - TC7126A: 35ppm/°C, Typical

• Zero Reading with Zero Input

• Low Noise: 15μVP-P

• High Resolution: 0.05%

• Low Input Leakage Current: 1pA Typ., 10pA Max.

• Precision Null Detectors with True Polarity at Zero

• High-Impedance Differential Input

• Convenient 9V Battery Operation with Low-Power

  Dissipation: 500μW Typ., 900μW Max.

Applications:

• Thermometry

• Bridge Readouts: Strain Gauges, Load Cells, Null Detectors

• Digital Meters and Panel Meters:

  - Voltage/Current/Ohms/Power, pH

• Digital Scales, Process Monitors