TC7126

Features:

• Internal Reference with Low Temperature Drift
- TC7126: 80ppm/°C Typical
- TC7126A: 35ppm/°C Typical
• Zero Reading with Zero Input
• Low Noise: 15µVP-P
• High Resolution: 0.05%
• Low Input Leakage Current: 1pA Typ., 10pA Max.
• Precision Null Detectors with True Polarity at Zero
• High-Impedance Differential Input
• Convenient 9V Battery Operation with Low Power Dissipation: 500µW Typ., 900µWMax.




Application

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




Pinout






Specifications

Parameter NameValueSupply Voltage (V)9Power (mW)0.5Hold FunctionNoFor DMM, DPM, data loggersNoResolution (Digits)3.5Resolution (Counts)2000Display TypeLCD Temp. Range (°C)-25 to 85

Parameter Name	Value
Supply Voltage (V)	9
Power (mW)	0.5
Hold Function	No
For DMM, DPM, data loggers	No
Resolution (Digits)	3.5
Resolution (Counts)	2000
Display Type	LCD
Temp. Range (°C)	-25 to 85

Supply Voltage (V+ to V-) ......................................... 15V
Analog Input Voltage (either Input) (Note 1) ... V+ to VReference
Input Voltage (either Input) ..................... V+ to VClock
Input .............................................................. Test to V+
Package Power Dissipation (TA  70°C) (Note 2):
44-Pin PQFP..........................................................1.00W
40-Pin PLCC..........................................................1.23W
44-Pin PDIP ..........................................................1.23W
Operating Temperature Range:
C (Commercial) Devices.......................... 0°C to +70°C
I (Industrial) Devices .......................... -25°C to +85°C
Storage Temperature Range.............. -65°C to +150°C

Description

The TC7126A is a 3-1/2 digit CMOS analog-to-digital converter (ADC)containing all the active components necessary to construct a 0.05%resolution measurement system.Seven-segment decoders,digit and polarity drivers, voltage reference,and clock circuit are integrated on-chip. The TC7126A directly drives a liquid crystal display (LCD), and includes a backplane driver. A low-cost,high-resolution indicating meter requires only a display,four resistors,and four capacitors. The TC7126A's extremely low power drain and 9V battery operation make it ideal for portable applications. The TC7126A reduces linearity error to less than 1 count.Roll-over error (the difference in readings for equal magnitude but opposite polarity input signals)is below ±1 count.High-impedance differential inputs offer 1 pA leakage current and a 10 12 ? input impedance.The 15 VP-P noise performance guarantees a "rock solid"reading,and the auto-zero cycle guarantees a zero display reading with a 0V input. The TC7126A features a precision, low-drift internal voltage reference an disfunctionally identical to the TC7126. A low-drift external reference is not normally required with the TC7126A.

The TC7126A is a 3-1/2 digit CMOS analog-to-digital converter (ADC)containing all the active components necessary to construct a 0.05%resolution measurement system.Seven-segment decoders,digit and polarity drivers, voltage reference,and clock circuit are integrated on-chip. The TC7126A directly drives a liquid crystal display (LCD), and includes a backplane driver. A low-cost,high-resolution indicating meter requires only a display,four resistors,and four capacitors. The TC7126A's extremely low power drain and 9V battery operation make it ideal for portable applications. The TC7126A reduces linearity error to less than 1 count.Roll-over error (the difference in readings for equal magnitude but opposite polarity input signals)is below ±1 count.High-impedance differential inputs offer 1 pA leakage current and a 10 12 ? input impedance.The 15 VP-P noise performance guarantees a "rock solid"reading,and the auto-zero cycle guarantees a zero display reading with a 0V input. The TC7126A features a precision, low-drift internal voltage reference an disfunctionally identical to the TC7126. A low-drift external reference is not normally required with the TC7126A.