AS89020

Analog To Digital Converters (ADC) Overview

The AS89020 is a 4-channel, current-input analog-to-digital converter (ADC) integrating transimpedance amplifiers (TIA) and a 12-bit successive approximation register (SAR) ADC. It supports sampling rates up to 100 kS/s with sensitivity reaching 2.8 pA/LSB. The programmable full-scale range spans from 11.7 nA to 12 µA via the SW_RX register. Powered by 2.7 V to 3.6 V, it operates between -25 °C and 85 °C. Key electrical parameters include a supply current of 10.5 mA at 3.6 V, 1 µA in power-down mode, and an absolute tolerance of equivalent ADC reference current ranging from -5% to 10%.

Analog To Digital Converters (ADC) Feature Summary

• Four independent channels with individually programmable TIA gain stages.
• 12-bit resolution with adjustable full-scale input current ranges.
• Integrated temperature compensation for high absolute accuracy.
• Fast SPI interface supporting clock frequencies up to 16 MHz.

Analog To Digital Converters (ADC) Applications

• Precise conversion of photo currents for UV, VIS, and IR optical sensors.
• Measurement of chromaticity coordinates and color temperatures for display backlight control.
• Reflective and transmitted light analysis for quality management and sorting.
• Photometry applications including brightness and color coordinate measurement.

Analog To Digital Converters (ADC) Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and tape-and-reel specifications. Confirm that the external resistor REXT meets the required 200 kΩ value and low temperature coefficient for optimal performance. Ensure supply voltage constraints are strictly observed during ramp-up to prevent damage.

Analog To Digital Converters (ADC) Selection Notes

Select appropriate gain settings via the SW_RX register to match the expected input current range for each channel. Ensure the external resistor connected to the REXT pin has a tight tolerance and low temperature coefficient to maintain conversion accuracy. Verify that the SPI clock frequency does not exceed 10 MHz if maximum 12-bit accuracy is required under all operating conditions.

Analog To Digital Converters (ADC) Part Context

The AS89020 belongs to a series of multi-channel transimpedance amplifier ICs designed for optoelectronic sensor signal processing. It combines current-to-voltage conversion and digitization in a single SSOP20 package. This integration reduces component count and board space compared to discrete TIA and ADC solutions.

Analog To Digital Converters (ADC) Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided datasheet. Evaluate alternative devices based on channel count, resolution, and package compatibility only after verifying technical parameter alignment.