AD9840AJSTZ

Overview

The AD9840AJSTZ is a complete 10-bit, 40 MSPS CCD signal processor designed for digital video and imaging applications. It features a single-channel architecture with a 40 MHz Correlated Double Sampler (CDS), a 2 dB to 36 dB Variable Gain Amplifier (VGA), and low-noise clamp circuits. The device operates from a single 3 V supply, consuming typically 155 mW. It includes a 10-bit A/D converter with 2.0 V full-scale input range and a 3-wire serial interface for register configuration. Packaged in a 48-lead LQFP, it supports operating temperatures from -20°C to +85°C.

Feature Summary

• Integrates a 40 MHz Correlated Double Sampler with programmable gain ranging from -2 dB to +10 dB.
• Includes a digitally controlled Variable Gain Amplifier offering a gain range of 2 dB to 36 dB with 10-bit resolution.
• Features dedicated auxiliary inputs (AUX1 and AUX2) for processing analog video signals without CDS functionality.
• Provides internal optical black clamping and preblanking functions to optimize signal integrity.

Applications

• Digital Video Camcorders
• Digital Still Cameras
• Industrial Imaging Systems

Procurement Notes

Verify the specific suffix 'JSTZ' corresponds to the commercial temperature range (-20°C to +85°C) and lead-free RoHS compliance as documented in the ordering guide. Confirm the package type is the 48-lead Thin Plastic Quad Flatpack (LQFP). Ensure ESD precautions are observed during handling due to the device's sensitivity.

Selection Notes

Select this component when interfacing with interlaced or progressive scan area CCD arrays requiring high-speed analog conditioning. It is suitable for systems needing a single-supply 3 V operation with integrated DC restoration and black level correction. Consider the AUX modes if CDS is not required for the specific sensor application.

Part Context

The AD9840A is part of Analog Devices' family of CCD signal processors, succeeding earlier models like the AD9801 and AD9803. It offers an expanded 2 V ADC full-scale range compared to previous 1 V designs, improving noise performance. The AJ variant denotes the commercial temperature grade within the broader AD9840A product line.

Replacement Considerations

Direct replacements include other AD9840A variants such as the AD9840AKSTZ for industrial temperature ranges. For legacy compatibility, consider the AD9843, though pinouts and features may differ. Verify that any substitute maintains the 40 MSPS clock rate and 10-bit resolution requirements.