TC7116/A/TC7117/A
3-1/2 Digit Analog-to-Digital Converters with Hold
Features
General Description
• Low Temperature Drift Internal Reference
- TC7116/TC7117 80 ppm/°C Typ.
- TC7116A/TC7117A 20 ppm/°C Typ.
• Display Hold Function
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 liq-
uid crystal displays (LCDs) and includes a backplane
driver. The TC7117A drives common anode light emit-
ting diode (LED) displays directly with an 8mA drive
current per segment.
• 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
These devices incorporate a display hold (HLDR) func-
tion. The displayed reading remains indefinitely, as
long as HLDR is held high. Conversions continue, but
output data display latches are not updated. The refer-
• True Polarity Indication for Precision Null
Applications
• Convenient 9V Battery Operation:
(TC7116/TC7116A)
• High Impedance CMOS Differential Inputs: 1012Ω
ence low input (V
-) is not available, as it is with the
REF
TC7106/7107. V
- is tied internally to analog com-
REF
mon in the TC7116A/7117A devices.
• Low Power Operation: 10mW
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
Applications
• Thermometry
12
offer 1pA leakage current and a 10 Ω input imped-
• Bridge Readouts: Strain Gauges, Load Cells,
Null Detectors
ance. The 15µV
noise performance enables a “rock
P-P
solid” reading. The auto-zero cycle ensures a zero dis-
play reading with a 0V input.
• Digital Meters: Voltage/Current/Ohms/Power, pH
• Digital Scales, Process Monitors
• Portable Instrumentation
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.
Device Selection Table
Package Code
Package
Temperature Range
CPL
IJL
40-Pin PDIP
40-Pin CERDIP
44-Pin PQFP
44-Pin PLCC
0°C to +70°C
-25°C to +85°C
0°C to +70°C
0°C to +70°C
CKW
CLW
2002 Microchip Technology Inc.
DS21457B-page 1