AD9840AJSTZRL

Overview

The AD9840AJSTZRL is a complete analog signal processor for CCD applications, featuring a 40 MHz single-channel architecture. It integrates an input clamp, correlated double sampler (CDS), digitally controlled variable gain amplifier (VGA), black level clamp, and a 10-bit A/D converter. The device operates from a 3 V single supply with typical power consumption of 155 mW. Key specifications include a 40 MSPS CDS with programmable gain from -2 dB to +10 dB, a VGA with 2 dB to 36 dB range, and a 10-bit ADC with 2.0 V full-scale input. It utilizes a 3-wire serial interface for register programming and is housed in a 48-lead LQFP package.

Feature Summary

• Integrates a 40 MSPS Correlated Double Sampler (CDS) with programmable gain resolution.
• Includes a Variable Gain Amplifier (VGA) offering a wide gain range for signal conditioning.
• Features low noise clamp circuits and an analog preblanking function for accurate black level correction.
• Provides auxiliary inputs (AUX1/AUX2) for processing standard analog video signals.

Applications

• Digital Video Camcorders
• Digital Still Cameras
• Industrial Imaging

Procurement Notes

Verify the specific suffix 'JSTZRL' against the manufacturer's current ordering guide to confirm package type and reel configuration. Ensure compatibility with existing PCB footprints for the 48-lead LQFP form factor. Confirm that the component meets all required environmental and regulatory standards for the target deployment region before finalizing procurement plans.

Selection Notes

Select this component when a high-speed, single-channel CCD signal chain is required within a compact footprint. The integrated VGA and CDS stages reduce external component count compared to discrete solutions. Consider the 3 V supply requirement and 155 mW power dissipation for thermal management in portable devices. Verify that the 10-bit resolution and 40 MSPS speed meet the system's image quality and frame rate specifications.

Part Context

The AD9840A belongs to Analog Devices' family of CCD signal processors, designed to replace multi-chip solutions. It consolidates functions typically found in separate clamp, CDS, VGA, and ADC chips. This integration simplifies board layout and improves signal integrity by minimizing inter-stage noise coupling. It serves as a direct upgrade path for systems previously using older generation CCD front-end architectures.

Replacement Considerations

Check for pin-compatible alternatives within the AD984x series if lead times are critical. Verify that any substitute maintains the same 40 MSPS clock rate and 10-bit resolution. Ensure the replacement supports the same 3-wire serial interface protocol to avoid firmware modifications.