AD9844AJST

Overview

The AD9844AJST is a complete analog signal processor for CCD applications, featuring a 20 MHz single-channel architecture. It includes a 12-bit A/D converter with a 2 V full-scale input range and 65 mW power consumption at 2.7 V. The device operates from a single 3 V supply within a -20°C to +85°C temperature range. Key specifications include a maximum clock rate of 20 MHz, 10-bit VGA gain control (2 dB to 36 dB), and 6-bit CDS gain resolution (-2 dB to 10 dB). It utilizes a 3-wire serial interface for register configuration and is housed in a 48-lead LQFP package.

Feature Summary

• Integrated correlated double sampler (CDS) with programmable gain adjustment for noise rejection.
• Variable gain amplifier (VGA) providing wide dynamic range signal conditioning.
• On-chip black level clamp and optical black clamp loops for offset correction.
• 12-bit high-speed analog-to-digital converter optimized for low power operation.

Applications

• Digital still cameras
• Digital video camcorders
• PC cameras

Procurement Notes

Verify the specific suffix 'JST' against the manufacturer's current ordering guide to confirm package type and temperature grade. Confirm availability status as this component may be discontinued or subject to last-time buy restrictions. Ensure ESD precautions are observed during handling due to sensitivity.

Selection Notes

Select this component for systems requiring a single-supply CCD interface with integrated signal conditioning. Verify that the 20 MHz sampling rate meets the target frame rate requirements. Ensure the 3 V logic levels are compatible with the downstream image processing ASIC or microprocessor.

Part Context

The AD9844A belongs to Analog Devices' family of CCD signal processors designed for consumer imaging. It serves as an analog front end that simplifies system design by integrating clamping, amplification, and conversion functions previously handled by discrete components.

Replacement Considerations

Check for direct pin-compatible upgrades within the AD984x series. Verify functional equivalence regarding gain ranges and ADC resolution if substituting with other CCD AFEs.