ICL7135CAI

ADCs/DACs - Special Purpose Overview

The ICL7135CAI is a 4-1/2 digit analog-to-digital converter (ADC) manufactured by Analog Devices Inc. under the Maxim Integrated brand. It utilizes dual-slope integration architecture to provide high-resolution conversion with a dynamic range of 0 to 19,999 counts. The device features a multiplexed BCD output interface and operates within a supply voltage range of 4V to 6V. Key electrical parameters include a sampling rate of 3 samples per second (SPS), a power dissipation of 1 W, and a supply current of 1 mA. It is housed in an SSOP-28 surface-mount package and supports an operating temperature range from 0°C to +70°C.

ADCs/DACs - Special Purpose Feature Summary

• 4-1/2 Digit Resolution: Provides 19,999 count resolution with ±1 count overall non-linearity error.
• Dual-Slope Architecture: Ensures strong anti-interference capability and high accuracy for DC measurements.
• Multiplexed BCD Output: Outputs data via a time-multiplexed Binary-Coded Decimal interface to reduce pin count.
• Integrated Display Driver: Includes internal clock generation and display control logic for direct LED/LCD interfacing.

ADCs/DACs - Special Purpose Applications

• Digital Panel Meters
• Precision Temperature Transmitters
• Low Resistance Measurement Instruments
• Electronic Scales

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific suffix 'CAI' against the manufacturer's official datasheet to confirm the SSOP-28 package and industrial temperature grade. Confirm RoHS compliance status as indicated by the '+' suffix in related part numbers like ICL7135CAI+T. Check for obsolescence or limited availability status directly with authorized distributors, as legacy ADCs may have restricted stock.

ADCs/DACs - Special Purpose Selection Notes

Select the ICL7135CAI when a cost-effective, high-accuracy 4-1/2 digit ADC with integrated display driving capabilities is required. Ensure the application requires a single-ended or differential input voltage range compatible with the 1.138V reference. Verify that the system design can accommodate the external RC components necessary for the dual-slope integration cycle and that the microcontroller interface supports the multiplexed BCD timing.

ADCs/DACs - Special Purpose Part Context

The ICL7135 belongs to the widely used ICL71xx series of dual-slope ADCs, which are standard components in precision measurement instrumentation. This series is known for its ability to reject line-frequency noise effectively. The CAI variant specifically denotes the commercial/industrial temperature range and the SSOP surface-mount packaging option, distinguishing it from PDIP through-hole versions like the ICL7135CPI.

ADCs/DACs - Special Purpose Replacement Considerations

Direct pin-compatible replacements include the TLC7135 (Texas Instruments) and ICL7135 variants from other manufacturers. Verify that substitute parts maintain the same 4-1/2 digit resolution, BCD output format, and supply voltage requirements before implementation.