Analog Devices Inc. AD9847KSTRL

Overview

AD9847KSTRL from Analog Devices is a 10-bit, 40 MSPS CCD signal processor with integrated timing driver for digital still camera image acquisition. It combines correlated double sampling (CDS), pixel gain amplifier (–2 dB to +10 dB), variable gain amplifier (2 dB to 36 dB), black level clamp, and 10-bit ADC in a single chip, operating from a 40 MHz master clock (CLI) with 500 ps timing resolution.

For engineers reviewing the AD9847KSTRL datasheet, AD9847KSTRL pinout, AD9847KSTRL application, or AD9847KSTRL equivalent, key selection criteria include its integrated 5 V horizontal/RGB drivers, programmable Precision Timing™ core for CCD clock edge placement, 48-lead LQFP package, and support for internal/external clamp pulse modes in high-resolution imaging systems.

Technical Context

The AD9847KSTRL implements a fully synchronized analog front end where CDS, PxGA, VGA, and ADC operate under clocks derived from the CLI input. Its Precision Timing™ core divides the 40 MHz CLI period into 48 discrete edge positions (t_CLI/48 ≈ 520.8 ps), enabling sub-nanosecond adjustment of RG, H1–H4, SHP, and SHD edges.

Timing generation is decoupled from digital control logic: horizontal pulses (CLPOB, CLPDM, HBLK, PBLK) can be generated internally via register-programmed sequences or accepted externally via dedicated digital inputs. All drivers (H1–H4, RG) deliver up to 24 mA into ≤100 pF loads at 5 V, with independent polarity, edge location (6-bit), and drive strength (3-bit) control per output.

Key Specifications

Pinout & Package

Packaged in a 48-lead LQFP (ST-48), the AD9847KSTRL features separate analog/digital power and ground domains (AVDD1–3, DVDD1–4; AVSS1–3, DVSS1–4), nine data outputs (D0–D9), four horizontal clock outputs (H1–H4), one reset gate output (RG), and dedicated timing control inputs (CLI, HD, VD, CLPOB, CLPDM, HBLK, PBLK).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9846ASTRL, the AD9847KSTRL adds 1-bit ADC resolution, PxGA, and extended VGA range-enabling superior dynamic range and color fidelity in premium imaging. Versus TDC1350IPWPR, it trades off ADC bits for full timing integration, reducing component count and timing skew in compact camera modules.

Availability

AD9847KSTRL is available at Aetrix Electronics and suitable for digital still camera sensor interfaces, high-resolution CCD imaging modules, and camera module reference designs requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD9847KSTRL 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 AD9847KSTRL belongs to Analog Devices' Precision Timing™ CCD signal processor family, designed specifically to replace multi-chip AFE + timing solutions in digital still cameras with a single, register-programmable IC delivering sub-nanosecond clock accuracy and low-noise analog signal conditioning.

FAQ

What is the maximum supported CCD pixel clock frequency for the AD9847KSTRL?

The AD9847KSTRL is specified for operation at a maximum master clock (CLI) frequency of 40 MHz, which corresponds to a 40 MSPS pixel rate. This is confirmed in the General Specifications table (Rev. A, p. –2) and defines the upper limit for CCD readout speed. Exceeding 40 MHz CLI violates absolute maximum ratings and may cause timing violations in the Precision Timing™ core or ADC sampling.

Does the AD9847KSTRL support external generation of horizontal timing pulses like CLPOB and CLPDM?

Yes, the AD9847KSTRL supports both internal and external modes for CLPOB and CLPDM. Register bits clpobdir (Address 0x84) and clpdmdir (Address 0x64) control this behavior: setting them to '1' configures the pins as digital inputs for externally supplied pulses, while '0' enables internal sequence generation. This dual-mode capability is documented in the CLPOB and CLPDM register descriptions (Rev. A, pp. –12–13).

What are the power supply requirements for the H1–H4 and RG drivers on the AD9847KSTRL?

The H1–H4 drivers require DVDD1 = 3.0 V to 5.5 V (typically 5.25 V), and the RG driver requires DVDD2 = 3.0 V to 5.5 V (also typically 5.25 V). These are specified in the General Specifications table (Rev. A, p. –2) and enable 5 V output swing into CCD loads. Separate ground domains (DVSS1, DVSS2) must be used to maintain noise isolation between horizontal and reset gate driver sections.

How does the Precision Timing™ core achieve 500 ps resolution with a 40 MHz CLI input?

The AD9847KSTRL's Precision Timing™ core divides the 40 MHz CLI period (25 ns) into 48 discrete edge positions, yielding a step size of 25 ns ÷ 48 ≈ 520.8 ps - rounded to "approximately 500 ps" in the datasheet. This is explicitly stated in the General Description (Rev. A, p. –1) and illustrated in Figure 4 (Rev. A, p. –15), where the internal pixel period grid is shown with 48 labeled positions (P[0] to P[47]).

Can the AD9847KSTRL's D0–D9 outputs be three-stated, and how is this controlled?

Yes, the AD9847KSTRL's D0–D9 outputs can be placed in high-impedance state via the tristateout bit (bit 5) in the ctlmode register (Address 0x06). When set to '1', the outputs are three-stated; when '0', they are actively driven. This functionality is defined in the AFE Register Breakdown section (Rev. A, p. –15) and allows shared data bus operation or power-down of downstream logic without signal contention.