AD9821KSTRL

Overview

The AD9821KSTRL is a complete analog signal processor for imaging applications that do not require Correlated Double Sampling (CDS). It features a 40 MHz single-channel architecture designed to sample and condition the outputs of CMOS imagers and CCD arrays already containing on-chip CDS. The signal chain consists of a differential input sample-and-hold amplifier (SHA), digitally controlled variable gain amplifier (VGA), black level clamp, and a 12-bit ADC. It operates from a single 3 V power supply, typically dissipating 150 mW, and is packaged in a 48-lead LQFP.

Feature Summary

• Integrates a differential input sample-and-hold amplifier with a 1 V p-p input range
• Includes a digitally controlled variable gain amplifier offering 0 dB to 36 dB gain adjustment
• Features a low noise optical black clamp circuit for offset correction
• Contains a 12-bit 40 MSPS A/D converter with straight binary data output coding

Applications

• Digital Still Cameras Using CMOS Imagers
• Industrial/Scientific Imaging

Procurement Notes

Verify the specific suffix KSTRL against the manufacturer's ordering guide to confirm package type and temperature range. Ensure compatibility with the 48-lead LQFP footprint and check for any RoHS compliance markings on the component marking. Confirm the device meets the required operating temperature range of -20°C to +85°C for your specific application environment.

Selection Notes

Select this component for imaging systems requiring a single-channel analog front end without internal CDS. It is suitable for sensors providing differential or single-ended signals within the 0 V to 1.8 V common-mode range. Consider the 12-bit resolution and 40 MSPS speed for applications needing moderate precision and high-speed data acquisition.

Part Context

The AD9821 is part of Analog Devices' imaging signal processor family, designed to interface directly with CMOS and CCD image sensors. It simplifies system design by integrating essential analog functions like sampling, amplification, clamping, and conversion into a single chip, reducing the need for external discrete components.

Replacement Considerations

Check for direct replacements such as the AD9821KST. Verify pinout compatibility and electrical specifications before substitution. Ensure the alternative part number matches the required package style and temperature rating for your design.

FAQ

What is the maximum clock rate for the AD9821?

The maximum clock rate for the AD9821 is 40 MHz.

How is the VGA gain adjusted?

The VGA gain is adjusted digitally via a 3-wire serial digital interface, offering 10-bit resolution with a range from 0 dB to 36 dB.

What is the input common-mode voltage range for VIN+ and VIN–?

The allowable voltage range for both VIN+ and VIN– inputs is from 0 V to 1.8 V.