Microchip Technology TC7117RCPL

General Description:

The TC7116A/TC7117A are 3-1/2 digit CMOS Analog to-Digital Converters (ADCs) containing all the active components necessary to construct a 0.05% resolution measurement system. Seven-segment decoders, polarity and digit drivers, voltage reference, and clock circuit are integrated on-chip. The TC7116A drives Liquid Crystal Displays (LCDs) and includes a back plane driver. The TC7117A drives common anode Light Emitting Diode (LED) displays directly with an 8mA drive current per segment.
These devices incorporate a display hold (HLDR) function. The displayed reading remains indefinitely, as long as HLDR is held high. Conversions continue, but output data display latches are not updated. The refer ence low input (VREF-) is not available, as it is with the TC7106/7107. VREF- is tied internally to analog common in the TC7116A/7117A devices.
The TC7116A/7117A reduces linearity error to less than 1 count. Rollover error (the difference in readings for equal magnitude but opposite polarity input signals) is below ±1 count. High-impedance differential inputs offer 1pA leakage current and a 1012 input imped ance. The 15VP-P noise performance enables a “rock solid” reading. The auto-zero cycle ensures a zero display reading with a 0V input.
The TC7116A and TC7117A feature a precision, low drift internal reference, and are functionally identical to the TC7116/TC7117. A low drift external reference is not normally required with the TC7116A/TC7117A.

Features:

• Low Temperature Drift Internal Reference:
- TC7116/TC7117 80 ppm/°C, Typ.
- TC7116A/TC7117A 20 ppm/°C, Typ.
• Display Hold Function
• Directly Drives LCD or LED Display
• Zero Reading with Zero Input
• Low Noise for Stable Display:
- 2V or 200mV Full Scale Range (FSR)
• Auto-Zero Cycle Eliminates Need for Zero
• Adjustment Potentiometer
• True Polarity Indication for Precision Null Applications
• Convenient 9V Battery Operation: (TC7116/TC7116A)
• High-Impedance CMOS Differential Inputs: 1012Ω
• Low-Power Operation: 10mW

Applications:

• Thermometry
• Bridge Readouts: Strain Gauges, Load Cells, Null Detectors
• Digital Meters: Voltage/Current/Ohms/Power, pH
• Digital Scales, Process Monitors
• Portable Instrumentation