TC7129CLW

ADCs/DACs - Special Purpose Overview

The TC7129CLW is a 4-1/2 digit Analog-to-Digital Converter (ADC) fabricated in low-power CMOS technology. It features direct multiplexed Liquid Crystal Display (LCD) driving capabilities for four digits, decimal points, and annunciators. The device utilizes a successive integration technique to achieve better than 0.005% full-scale accuracy with a resolution of 10 µV on the 200 mV scale. Key electrical specifications include a maximum supply current of 1.3 mA at 9 V, a common mode rejection ratio of 110 dB, and an operating temperature range from 0°C to +70°C.

ADCs/DACs - Special Purpose Feature Summary

• Directly drives a multiplexed LCD with 4-1/2 digits, decimal points, and indicators
• Successive integration technique provides high resolution down to 10 µV per count
• Integrated continuity indicator and low battery detection logic
• Internal phase compensation eliminates external components

ADCs/DACs - Special Purpose Applications

• Full-featured digital multimeters
• High-resolution digital measurement devices
• Battery-powered precision instruments

ADCs/DACs - Special Purpose Procurement Notes

Verify that the specific ordering suffix 'CLW' corresponds to the 44-pin PLCC package variant. Confirm the manufacturer's lifecycle status, as older ADC models may be subject to discontinuation or obsolescence notices. Ensure the procurement channel provides valid traceability documentation for the component lot.

ADCs/DACs - Special Purpose Selection Notes

Select this component when designing systems requiring direct LCD interfacing without external drivers. The internal phase compensation simplifies the bill of materials compared to predecessors like the ICL7129. Ensure the application environment remains within the specified 0°C to +70°C operating temperature range for guaranteed performance.

ADCs/DACs - Special Purpose Part Context

The TC7129 belongs to Microchip's family of 4-1/2 digit analog-to-digital converters designed for high-resolution measurements. It serves as a modern replacement for legacy parts such as the ICL7129, offering improved power efficiency and simplified circuit design through integrated features like auto-zeroing and continuous monitoring outputs.

ADCs/DACs - Special Purpose Replacement Considerations

The TC7129 is a pin-compatible replacement for the ICL7129. When substituting, remove any external phase compensation capacitors and resistors previously required between pins 26 and 28, as these are not needed for stable operation with the TC7129.