TC7129

Features:

• Count Resolution: ±19,999
• Resolution on 200mV Scale: 10µV
• True Differential Input and Reference
• Low Power Consumption: 500µA at 9V
• Direct LCD Driver for 4-1/2 Digits, Decimal Points, Low Battery Indicator, and Continuity Indicator
• Over Range and Under Range Outputs
• Range Select Input: 10:1
• High Common Mode Rejection Ratio: 110dB
• External Phase Compensation Not Required




Application

• Full Featured Multimeters
• Digital Measurement Devices




Pinout






Specifications

Parameter NameValueSupply Voltage (V)9Power (mW)4.5Hold FunctionNoFor DMM, DPM, data loggersNoResolution (Digits)4.5Resolution (Counts)20000Display TypeLCD Temp. Range (°C)0 to 70

Parameter Name	Value
Supply Voltage (V)	9
Power (mW)	4.5
Hold Function	No
For DMM, DPM, data loggers	No
Resolution (Digits)	4.5
Resolution (Counts)	20000
Display Type	LCD
Temp. Range (°C)	0 to 70

Supply Voltage (V+ to V-) ......................................... 15V
Reference Voltage (REF HI or REF LO) ......... V+ to VInput
Voltage (IN HI or IN LO) (Note 1)............................ V+ to
 VVDISP.............................................V+ to (DGND  0.3V)
Digital Input (Pins 1, 2, 19, 20,
21, 22, 27, 37, 39, 40) ................................. DGND to V+
Analog Input (Pins 25, 29, 30) ................V+ to VPackage
Power Dissipation (TA  70°C)
Plastic DIP .............................................................1.23W
PLCC .....................................................................1.23W
Plastic QFP .............................................................1.00W
Operating Temperature Range ............... 0°C to +70°C
Storage Temperature Range.............. -65°C to +150°C

Description

The TC7129 is a 4-1/2 digit analog-to-digital converter (ADC)that directly drives a multiplexed liquid crystal display (LCD).Fabricated in high-performance,low-power CMOS, the TC7129 ADC is designed specifically for high-resolution, battery-powered digital multimeter applications. The traditional dual-slope method of A/D conversion has been enhanced with a successive integration technique to produce readings accurate to better than 0.005% of full scale, and resolution down to 10V per count. The TC7129 includes features important to multimeter applications.It detects and indicates low-battery condition. A continuity output drives an annunciator on the display, and can be used with an external driver to sound an audible alarm.Overrange and underrange outputs and a range-change input provide the ability to create auto-ranging instruments.For snapshot readings,the TC7129 includes a latch-and-hold input to freeze the present reading. This combination of features makes the TC7129 the ideal choice for full-featured multimeter and digital measurement applications.

The TC7129 is a 4-1/2 digit analog-to-digital converter (ADC) that directly drives a multiplexed liquid crystal display (LCD). Fabricated in high performance, low power CMOS, the TC7129 ADC is designed specifically for high resolution, battery powered digital multimeter applications. The traditional dual slope method of A/D conversion has been enhanced with a successive integration technique to produce readings accurate to better than 0.005% of full scale, and resolution down to 10µV per count.

The TC7129 includes features important to multimeter applications. It detects and indicates low battery condition. A continuity output drives an annunciator on the display, and can be used with an external driver to sound an audible alarm. Over range and under rangeoutputs and a range change input provide the ability to create auto ranging instruments. For snapshot readings, the TC7129 includes a latch-and-hold input to freeze the present reading. This combination of features makes the TC7129 the ideal choice for full featured multimeter and digital measurement applications.