TC7136ACLW

ADCs/DACs - Special Purpose Overview

The TC7136ACLW is a low power, 3-1/2 digit analog-to-digital converter with integrated LCD drivers. It utilizes a dual-slope integrating architecture to achieve 0.05% resolution and 15µV peak-to-peak noise performance. The device features a high-impedance differential input with 1pA typical leakage current and includes precision null detectors for true polarity indication at zero. Designed for battery operation, it dissipates only 500µW typically at 9V supply. The TC7136A variant incorporates an improved internal zener reference with a temperature drift of 35ppm/°C typical, eliminating the need for external reference sources in many applications.

ADCs/DACs - Special Purpose Feature Summary

• Dual-slope ADC architecture with 3-1/2 digit resolution (1999 counts) and 0.05% linearity error.
• Internal voltage reference with 35ppm/°C typical temperature coefficient for the TC7136A.
• Low power consumption of 500µW typical, enabling convenient 9V battery operation.
• High-impedance differential inputs with 1pA typical leakage current and 15µV P-P noise.

ADCs/DACs - Special Purpose Applications

• Thermometry systems
• Bridge readouts for strain gauges and load cells
• Digital meters for voltage, current, ohms, and pH measurement
• Portable instrumentation

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific package configuration, as the CLW suffix denotes a 44-pin PLCC package. Confirm that the TC7136A specification meets the required temperature drift standards compared to the standard TC7136. Ensure the design accounts for the obsolete status if long-term availability is critical.

ADCs/DACs - Special Purpose Selection Notes

Select the TC7136A over the TC7136 when lower internal reference temperature drift (35ppm/°C vs 70ppm/°C) is required. Choose the CLW package for surface-mount PLCC compatibility. Ensure external component values, such as the integrating capacitor and resistor, are selected based on the desired full-scale range (200mV or 2V) and conversion rate.

ADCs/DACs - Special Purpose Part Context

The TC7136 series serves as a low-power alternative to the TC7126 and ICL7126, offering improved performance with minor changes to external passive components. The TC7136A specifically enhances the internal reference stability. This family is designed for direct replacement in existing 3-1/2 digit meter designs to upgrade accuracy and reduce power consumption.

ADCs/DACs - Special Purpose Replacement Considerations

The TC7136 is a drop-in replacement for the TC7126 and ICL7126. When replacing the standard TC7136 with the TC7136A, verify that the improved reference drift aligns with system requirements. No functional pin changes are required between the base models.