TC7106/A/TC7107/A
3-1/2 Digit Analog-to-Digital Converters
General Description
Features
• Internal Reference with Low Temperature Drift
- TC7106/7: 80ppm/°C Typical
The TC7106A and TC7107A 3-1/2 digit direct display
drive analog-to-digital converters allow existing 7106/
7107 based systems to be upgraded. Each device has
a precision reference with a 20ppm/°C max tempera-
ture coefficient. This represents a 4 to 7 times improve-
ment over similar 3-1/2 digit converters. Existing 7106
and 7107 based systems may be upgraded without
changing external passive component values. The
TC7107A drives common anode light emitting diode
(LED) displays directly with 8mA per segment. A low
cost, high resolution indicating meter requires only a
display, four resistors, and four capacitors.The
TC7106A low power drain and 9V battery operation
make it suitable for portable applications.
- TC7106A/7A: 20ppm/°C Typical
• Drives LCD (TC7106) or LED (TC7107)
Display Directly
• Zero Reading with Zero Input
• Low Noise for Stable Display
• Auto-Zero Cycle Eliminates Need for Zero
Adjustment
• True Polarity Indication for Precision Null
Applications
• Convenient 9V Battery Operation (TC7106A)
12
• High Impedance CMOS Differential Inputs: 10
Ω
The TC7106A/TC7107A 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
• Differential Reference Inputs Simplify Ratiometric
Measurements
• Low Power Operation: 10mW
12
offer 1pA leakage current and a 10 Ω input imped-
Applications
ance. The differential reference input allows ratiometric
measurements for ohms or bridge transducer mea-
• Thermometry
surements. The 15µV
noise performance ensures a
P–P
• Bridge Readouts: Strain Gauges, Load Cells, Null
Detectors
“rock solid” reading. The auto-zero cycle ensures a
zero display reading with a zero volts input.
• Digital Meters: Voltage/Current/Ohms/Power, pH
• Digital Scales, Process Monitors
• Portable Instrumentation
Device Selection Table
Package
Code
Temperature
Range
Package
Pin Layout
CPI
IPL
40-Pin PDIP
40-Pin PDIP
Normal
Normal
Normal
0°C to +70°C
-25°C to +85°C
-25°C to +85°C
IJL
40-Pin CERDIP
CKW
CLW
44-Pin PQFP Formed Leads 0°C to +70°C
44-Pin PLCC 0°C to +70°C
—
2002 Microchip Technology Inc.
DS21455B-page 1