General Description
The TC7135 4-1/2 digit A/D Converter (ADC) offers 50 ppm (1 part in 20,000) resolution with a maximum nonlinearity error of 1 count. An auto-zero cycle reduces zero error to below 10 µV and zero drift to 0.5 µV/°C. Source impedance errors are minimized by a 10 pA maximum input current. Rollover error is limited to ±1 count.

FEATUREs
• Low Rollover Error: ±1 Count Max
• Nonlinearity Error: ±1 Count Max
• Reading for 0V Input
• True Polarity Indication at Zero for Null Detection
• Multiplexed BCD Data Output
• TTL-Compatible Outputs
• Differential Input
• Control Signals Permit Interface to UARTs and
   Microprocessors
• Blinking Display Visually Indicates Overrange
   Condition
• Low Input Current: 1 pA
• Low Zero Reading Drift: 2 µV/°C
• Auto-Ranging Supported with Overrange and
   Underrange Signals
• Available in PDIP and Surface-Mount Packages

APPLICATIONs
• Precision Analog Signal Processor
• Precision Sensor Interface
• High Accuracy DC Measurements