Analog Devices Inc. AD9238BSTZ-40

Overview

AD9238BSTZ-40 from Analog Devices is a dual-channel, 12-bit, 40 MSPS analog-to-digital converter (ADC) fabricated in advanced CMOS. It features integrated sample-and-hold amplifiers, on-chip voltage reference, and differential analog inputs with 500 MHz bandwidth. Operating from a single 3 V supply (2.7–3.6 V), it delivers 70.2 dB SNR and 84.0 dBc SFDR at 9.7 MHz input, targeting IF sampling in wireless receivers and ultrasound front-ends.

For engineers reviewing the AD9238BSTZ-40 datasheet, AD9238BSTZ-40 pinout, AD9238BSTZ-40 application, or AD9238BSTZ-40 equivalent, this page provides verified specifications, validated LQFP-64 pin functions, confirmed dual-channel timing roles, and two rigorously cross-referenced alternative ADCs for direct system-level comparison.

Technical Context

The AD9238BSTZ-40 implements a multistage differential pipelined architecture with output error correction logic to guarantee 12-bit accuracy and no missing codes across −40°C to +85°C. Its dual SHA supports flexible differential or single-ended analog inputs (1 V_p-p to 2 V_p-p) and maintains >85 dB channel crosstalk isolation at 10 MHz.

It integrates a clock duty cycle stabilizer (DCS) that preserves AC performance over wide input clock duty cycle variation, and supports configurable data output formats (offset binary or twos complement) with multiplexed port selection via MUX_SELECT. Pipeline latency is fixed at 7 clock cycles.

Key Specifications

Pinout & Package

AD9238BSTZ-40 is packaged in a Pb-free, 64-lead LQFP (10 mm × 10 mm, 0.5 mm pitch) with exposed thermal pad connected to AGND. Pin 1 identifier located at top-left corner; all DNC pins must remain unconnected.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel ADC applications.

Compared with AD9238BSTZ-40, the -65 variant trades power for bandwidth headroom while preserving layout and firmware compatibility, whereas AD9248BSTZ-40 sacrifices efficiency and noise floor for quantization depth-making each optimal for distinct signal fidelity vs. power trade-offs in receiver front-ends.

Availability

AD9238BSTZ-40 is available at Aetrix Electronics and suitable for ultrasound equipment, IF sampling receivers, and battery-powered test instruments requiring stable component supply across extended production lifecycles.

Supply support for AD9238BSTZ-40 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 DSP technologies, headquartered in Norwood, MA, with design centers worldwide and ISO 9001-certified manufacturing.

The AD9238 product line delivers dual-channel, low-power, high-speed ADCs optimized for communications infrastructure, medical imaging, and portable instrumentation-designed to replace discrete ADC + reference + driver solutions with single-chip integration.

FAQ

What is the maximum analog input frequency supported by the AD9238BSTZ-40?

The AD9238BSTZ-40 specifies 500 MHz 3 dB analog input bandwidth, enabling faithful digitization of signals up to ~150 MHz (well beyond its 20 MHz Nyquist limit at 40 MSPS). Measured SFDR remains ≥80 dBc up to 32.5 MHz input, confirming usable performance in undersampled IF applications. The device's differential SHA architecture maintains integrity even at high input frequencies.

Does the AD9238BSTZ-40 require external reference components?

No. The AD9238BSTZ-40 integrates a precision 1.0 V internal voltage reference with ±35 mV output error and 0.8 mV load regulation. External reference is optional-only required if users need 0.5 V mode (via SENSE pin) or tighter initial accuracy than the internal reference provides. REFT/REFB pins connect directly to the internal reference for standard operation.

How does the clock duty cycle stabilizer (DCS) function in the AD9238BSTZ-40?

The DCS circuit in the AD9238BSTZ-40 actively corrects input clock duty cycle deviations between 30% and 70%, ensuring consistent aperture uncertainty (0.5 ps rms) and maintaining SNR/SFDR performance. When enabled (DCS pin = high), it eliminates the need for external clock conditioning circuits-critical for FPGA-driven clock sources with variable duty cycles.

Can both channels of the AD9238BSTZ-40 operate independently?

Yes. AD9238BSTZ-40 supports fully independent operation: CLK_A and CLK_B may be asynchronous, PDWN_A/PDWN_B control per-channel power-down, and OEB_A/OEB_B enable high-Z states on respective data buses. Crosstalk remains >85 dB, allowing simultaneous acquisition of unrelated signals-e.g., I/Q paths or dual-probe measurements-without mutual interference.

What package type and thermal characteristics apply to the AD9238BSTZ-40?

AD9238BSTZ-40 uses a 64-lead LQFP package (10 mm × 10 mm, 0.5 mm pitch) with exposed thermal pad soldered to AGND. Its thermal impedance is θ_JA = 54°C/W on a 4-layer board in still air. At 330 mW dissipation and 85°C ambient, junction temperature stays below 150°C-within safe operating limits-provided minimum 0.1 µF + 10 µF decoupling is applied to AVDD/DRVDD rails.