Analog Devices Inc. AD9843AJSTZ

Overview

AD9843AJSTZ from Analog Devices is a complete 10-bit, 20 MSPS CCD signal processor IC for analog front-end conditioning of interlaced and progressive-scan area CCD outputs. It integrates correlated double sampling (CDS) with programmable gain (–2 dB to +10 dB), a 2 dB–36 dB VGA, black-level clamping, and a 10-bit ADC - all operating from a single 3 V supply in a 48-lead LQFP package. It is deployed in digital still cameras and camcorders to digitize and normalize raw pixel data before ASIC-based image processing.

For engineers reviewing the AD9843AJSTZ datasheet, AD9843AJSTZ pinout, AD9843AJSTZ application, or AD9843AJSTZ equivalent, this page delivers verified functional identity, confirmed timing behavior (20 MHz DATACLK/SHP/SHD), validated power consumption (78 mW typical), and real-world use context across CCD-mode, AUX1-mode, and AUX2-mode configurations.

Technical Context

The AD9843AJSTZ implements a single-channel analog signal chain optimized for CCD output conditioning: input clamp → CDS → VGA → black-level clamp → 10-bit ADC. Its CDS stage uses two precisely timed rising-edge clocks (SHP and SHD) with 3 ns internal delay and supports dynamic gain adjustment via a 6-bit register (64 steps, –2 dB to +10 dB).

The VGA provides 10-bit resolution (1024 steps) over 2 dB–36 dB range using dual-region gain equations; its output drives the ADC's 2.0 V full-scale input. Three operational modes - CCD, AUX1 (ac-coupled video), and AUX2 (video clamp with 0–18 dB gain) - are selected via serial register control and share the same 3-wire interface (SCK/SL/SDATA) with 10 MHz max clock rate.

Key Specifications

Pinout & Package

AD9843AJSTZ is housed in a 48-lead LQFP (ST-48) package with exposed thermal pad. Pin functions are fully defined per Analog Devices Rev. 0 datasheet, including dedicated analog/digital grounds (AVSS/DVSS/DRVSS), dual analog supplies (AVDD1/AVDD2), and three independent analog inputs (CCDIN, AUX1IN, AUX2IN).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar CCD signal processor applications.

Compared with AD9844ASTZ and TDA8785HN/C1, AD9843AJSTZ uniquely balances programmability (CDS/VGA/clamp registers), single-supply operation, and 20 MSPS throughput in a compact LQFP - making it optimal for mid-tier digital imaging where configurability and power efficiency are critical.

Availability

AD9843AJSTZ is available at Aetrix Electronics and suitable for digital still cameras, digital video camcorders, and PC cameras requiring stable component supply, long-term lifecycle support, and traceable sourcing for volume production.

Supply support for AD9843AJSTZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and consumer markets since 1965.

The AD9843AJSTZ belongs to Analog Devices' CCD signal processor product line, designed specifically to replace discrete AFE solutions in portable imaging systems by integrating CDS, VGA, clamping, and ADC functions into a single 3 V, low-power IC.

FAQ

What is the maximum clock rate supported by the AD9843AJSTZ?

The AD9843AJSTZ supports a maximum DATACLK, SHP, and SHD clock rate of 20 MHz, enabling full-speed 20 MSPS sampling of CCD pixel data. This timing is validated across all operating modes (CCD, AUX1, AUX2) and ensures accurate CDS sampling, VGA settling, and ADC conversion within specified setup/hold windows.

Does the AD9843AJSTZ support multiple analog input configurations?

Yes, the AD9843AJSTZ supports three distinct analog input modes: CCD mode (via CCDIN with CDS), AUX1 mode (via AUX1IN with dc-biased ac-coupling), and AUX2 mode (via AUX2IN with integrated video clamp). Each mode uses dedicated timing and gain control registers, allowing flexible reuse of the same IC across different sensor types and signal formats.

How does the optical black clamp function in the AD9843AJSTZ?

The AD9843AJSTZ implements an optical black clamp loop that operates during the CCD's shielded black pixel interval. It compares the ADC output against a user-programmed clamp level (0–63.75 LSB) and applies correction via an internal 8-bit DAC. The loop updates per horizontal line and is enabled/disabled via Bit D5 in the Operation Register.

What power supply requirements does the AD9843AJSTZ have?

The AD9843AJSTZ operates from a single 3.0 V supply (range: 2.7 V to 3.6 V) for AVDD, DVDD, and DRVDD. It separates analog (AVSS), digital (DVSS), and driver (DRVSS) ground domains. Typical power dissipation is 78 mW in normal operation, dropping to 5 mW in standby and 1 mW in total shutdown mode.

Can the AD9843AJSTZ be used with non-CCD sensors such as CMOS image sensors?

The AD9843AJSTZ is optimized for CCD output characteristics - particularly correlated double sampling and optical black pixel handling - and is not designed for CMOS sensors, which typically output single-sampled, non-correlated signals. While AUX1/AUX2 modes accept generic analog video, they lack CMOS-specific features like rolling shutter correction or on-chip timing generation.