Analog Devices Inc. AD9843AJSTRL

Overview

AD9843AJSTRL from Analog Devices is a complete 10-bit, 20 MSPS CCD signal processor IC featuring correlated double sampling (CDS), 2 dB to 36 dB digitally programmable VGA, black-level clamp, and integrated 10-bit ADC - all in a single 48-lead LQFP package. It serves as the analog front end for interlaced/progressive scan CCD arrays in digital imaging systems, delivering low-noise signal conditioning with 0.2 LSB_rms total output noise and ±0.4 LSB DNL.

For engineers reviewing the AD9843AJSTRL datasheet, AD9843AJSTRL pinout, AD9843AJSTRL application, or AD9843AJSTRL equivalent, this page provides verified functional identity, confirmed 48-pin LQFP mapping, validated CCD-mode timing constraints (tSHP = 7–12.5 ns, tSHD = 7–12.5 ns), real-world power consumption (78 mW @ 3.0 V), and two confirmed alternative AFEs with documented gain-range and mode differences.

Technical Context

The AD9843AJSTRL implements a single-channel CCD signal chain comprising input clamp → CDS (with programmable –2 dB to +10 dB gain in 64 steps) → VGA (2–36 dB, 10-bit resolution) → black-level clamp → 10-bit ADC. Its internal timing engine synchronizes SHP/SHD sampling edges with <3 ns aperture delay and supports three operating modes: CCD-mode (default), AUX1-mode (ac-coupled video, 0–36 dB VGA), and AUX2-mode (video clamping, 0–18 dB VGA).

It uses a 3-wire serial interface (SCK, SDATA, SL) for register configuration - including Operation, VGA Gain, Clamp Level, Control, and CDS Gain registers - with simultaneous update on SL rising edge. Power management includes Fast Recovery (45 mW, 0.1 ms wake-up), Standby (5 mW), and Total Power-Down (1 mW) modes.

Key Specifications

Pinout & Package

AD9843AJSTRL is housed in a 48-lead Thin Plastic Quad Flatpack (LQFP), ST-48 package (θ_JA = 92°C/W), with exposed pad not electrically connected. Pin 1 identifier located at top-left corner (top view). Analog and digital grounds are segregated (AVSS ×3, DVSS ×3, DRVSS ×2) to minimize coupling; decoupling capacitors required on all AVDD/DVDD/DRVDD pins per datasheet layout guidance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar CCD analog front end applications.

Compared with AD9844ASTZ and TDA8785H/N1, AD9843AJSTRL uniquely balances single-channel integration, full programmability (CDS/VGA/clamp), and ultra-low power - making it the most flexible and compact solution for new CCD-based camera designs requiring adaptive gain control and thermal stability.

Availability

AD9843AJSTRL is available at Aetrix Electronics and suitable for digital still cameras, video camcorders, and PC-based imaging systems requiring stable component supply, long-term lifecycle support, and traceable sourcing from authorized channels.

Supply support for AD9843AJSTRL 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD984x family was designed specifically as highly integrated, low-power CCD analog front ends for portable and embedded imaging applications - emphasizing noise performance, programmable gain flexibility, and single-supply operation.

FAQ

What is the maximum input voltage range supported by AD9843AJSTRL in CCD-mode?

The AD9843AJSTRL supports up to 1.5 V_p-p input range in CCD-mode when configured with –2 dB CDS gain. With default 4 dB CDS gain, the maximum allowable input is 1.0 V_p-p; at 10 dB CDS gain, it reduces to 0.5 V_p-p. These limits prevent saturation of the internal signal chain and maintain linearity across the full VGA gain range. All values are specified in the CCD-Mode Specifications table on page 3 of the AD9843A datasheet.

Does AD9843AJSTRL support both interlaced and progressive scan CCD sensors?

Yes, AD9843AJSTRL supports both interlaced and progressive scan CCD sensors. Its 20 MSPS sampling rate and flexible timing architecture - including independently controllable SHP, SHD, CLPOB, and CLPDM clocks - allow synchronization with diverse CCD timing requirements. The internal timing generator accommodates varying horizontal blanking intervals and optical black pixel placements, as confirmed in Figures 5 and 6 of the datasheet.

How does the optical black clamp function in AD9843AJSTRL?

The optical black clamp in AD9843AJSTRL operates during the optical black pixel interval on each line, comparing the ADC output against a user-programmed clamp level (0–63.75 LSB) stored in the Clamp Level Register. The resulting error is filtered and applied via an internal 8-bit DAC to correct residual offsets. This closed-loop system tracks low-frequency black-level drift and maintains consistency across temperature and gain changes - a key advantage over open-loop DC restoration methods.

Can AD9843AJSTRL be used with non-CCD video sources like NTSC or PAL signals?

Yes, AD9843AJSTRL supports NTSC and PAL video signals via its AUX2-mode. In this mode, the AUX2IN pin (Pin 34) accepts ac-coupled composite video, and the on-chip video clamp circuit automatically senses the most negative portion of the signal to establish black level. VGA gain is adjustable from 0 dB to 18 dB using the upper 9 bits of the VGA Gain Register, enabling compatibility with standard-definition analog video formats.

What are the power-down modes available on AD9843AJSTRL and their recovery times?

AD9843AJSTRL offers three power-down modes: Fast Recovery (45 mW, 0.1 ms wake-up), Standby (5 mW, 1 ms wake-up), and Total Power-Down (1 mW, 3 ms wake-up). Recovery is initiated by toggling the STBY pin or applying clocks - no external reset is required. These modes are controlled via the Operation Register (Address 0x00), and all retain register contents except in Total Power-Down, where registers reset to defaults upon wake-up.