Analog Devices Inc. AD9848AKST

Overview

AD9848AKST from Analog Devices is a 10-bit, 20 MHz CCD signal processor with integrated analog front end (CDS, PxGA, VGA, black level clamp) and precision timing driver for digital still cameras. It delivers 2 dB to 36 dB programmable gain, 1 ns timing resolution at 20 MSPS, and on-chip 3 V horizontal/RGB drivers in a 48-lead LQFP package.

For engineers reviewing the AD9848AKST datasheet, AD9848AKST pinout, AD9848AKST application, or AD9848AKST equivalent, key selection criteria include pixel-rate compatibility (20 MHz), 10-bit ADC performance, internal clamp pulse generation (CLPOB/CLPDM), and LQFP thermal characteristics for compact camera modules.

Technical Context

The AD9848AKST implements a correlated double sampling (CDS) architecture with a dedicated Pixel Gain Amplifier (PxGA®) offering –2 dB to +10 dB gain in 64 monotonic steps, followed by a 10-bit VGA with 1024-step 2–36 dB range. Its Precision Timing™ Core synchronizes all clocks-including H1–H4, RG, SHP, SHD-to the master CLI input with 6 ns delay and 1 ns resolution at 20 MSPS.

It supports both internal and external timing modes: internal mode generates CLPOB, CLPDM, PBLK, and HBLK pulses via programmable registers; external mode accepts these signals directly. The 3-wire serial interface (SL/SCK/SDATA) configures all timing parameters and AFE settings with VD/HD or SL-triggered updates.

Key Specifications

Pinout & Package

AD9848AKST is housed in a 48-lead Thin Plastic Quad Flatpack (LQFP), ST-48 package with 0.5 mm pitch and exposed thermal pad. Package thermal resistance θ_JA = 92°C/W supports passive cooling in space-constrained camera modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9849AKST and TDC1304D, AD9848AKST uniquely balances integration (AFE + timing), 10-bit fidelity, and 20 MHz throughput in a thermally optimized LQFP-making it optimal for cost-sensitive, size-constrained 10 MP digital still camera designs where 3 V logic compatibility is required.

Availability

AD9848AKST is available at Aetrix Electronics and suitable for digital still camera sensor interfaces, medical endoscope imaging modules, and industrial machine vision inspection systems requiring stable component supply and long-term production continuity.

Supply support for AD9848AKST 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 semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD9848AKST belongs to Analog Devices' CCD Signal Processor product line, engineered specifically to integrate analog front-end functions and high-resolution timing generation into a single chip for digital imaging applications.

FAQ

What is the maximum pixel clock frequency supported by the AD9848AKST?

The AD9848AKST supports a maximum pixel clock frequency of 20 MHz, as specified in its general electrical characteristics. This limit is defined by the internal ADC conversion rate and timing core architecture. Exceeding 20 MHz may result in data loss, increased DNL error, or failure to meet the 1 ns timing resolution guarantee. The CLI input must be precisely 20 MHz for full-spec operation.

Does the AD9848AKST include an integrated ADC, and what is its resolution?

Yes, the AD9848AKST integrates a 10-bit analog-to-digital converter. Its ADC features guaranteed monotonicity, no missing codes, ±0.4 LSB typical differential nonlinearity, and a full-scale input voltage of 2.0 V. This resolution is fixed and cannot be configured to 12 bits-the AD9849AKST variant provides that capability.

Can the AD9848AKST generate CCD horizontal timing signals internally?

Yes, the AD9848AKST can generate H1–H4 and RG timing signals internally using its Precision Timing™ Core. Edge positions for all four horizontal clocks and the reset gate are fully programmable via register writes over the 3-wire serial interface, with 1 ns resolution at 20 MSPS. Internal generation eliminates the need for external timing ASICs in most digital still camera designs.

What are the power supply requirements for the AD9848AKST digital I/O sections?

The AD9848AKST requires four separate digital supply rails: DVDD1/DVSS1 for H1–H4 drivers (2.7–3.6 V), DVDD2/DVSS2 for RG driver (2.7–3.6 V), DVDD3/DVSS3 for D0–D9 data outputs (3.0 V nominal), and DVDD4/DVSS4 for control inputs (SL/SCK/SDATA/VD/HD) (3.0 V nominal). Mixing or sharing these rails violates absolute maximum ratings and degrades timing accuracy.

How does the AD9848AKST handle black level clamping for CCD sensors?

The AD9848AKST implements black level clamping using two dedicated digital inputs-CLPOB (optical black) and CLPDM (dummy black)-to define integration windows. It performs correlated double sampling (CDS) followed by a digitally programmable clamp level (256 steps, 0–63.75 LSB) applied at the ADC output stage. Clamp level resolution and monotonicity are guaranteed across temperature.