General Description
The TC820 is a 3-3/4 digit, multi-measurement system especially suited for use in portable instruments. It integrates a dual slope A/D converter, auto-ranging frequency counter and logic probe into a single 44-pin surface mount, or 40-pin through hole package. The TC820 operates from a single 9V input voltage (battery) and features a built-in battery low flag. Function and decimal point selection are accomplished with simple logic inputs designed for direct connection to an external microcontroller or rotary switch.

FEATUREs
• Multiple Analog Measurement System
   - Digit A/D Converter
   - Frequency Counter
   - Logic Probe
• Low Noise A/D Converter:
   - Differential Inputs: (1pA Bias Current)
   - On-Chip 50ppm/°C Voltage Reference
• Frequency Counter:
   - 4MHz Maximum Input Frequency
   - Auto-Ranging Over Four Decade Range
• Logic Probe:
   - Two LCD Annunciators
   - Buzzer Driver
• 3-3/4 Digit Display with Over Range Indicator
• LCD Display Driver with Built-in Contrast Control
• Data Hold Input for Comparison Measurements
• Low Battery Detect with LCD Annunciator
• Under Range and Over Range Outputs
• On-Chip Buzzer Driver with Control Input
• 40-Pin Plastic DIP, 44-Pin Plastic Flat Pack, or 44-Pin PLCC Packages