Analog Devices Inc. AD9248BSTZ-65

Overview

AD9248BSTZ-65 from Analog Devices is a dual-channel, 14-bit, 65 MSPS analog-to-digital converter (ADC) with differential input architecture, integrated voltage reference, and clock duty cycle stabilizer. It delivers SNR = 71.6 dB and SFDR = 80.5 dBc at Nyquist, operates from a single 3 V supply (2.7–3.6 V), and targets IF sampling in wireless receivers and ultrasound front-ends.

For engineers reviewing the AD9248BSTZ-65 datasheet, AD9248BSTZ-65 pinout, AD9248BSTZ-65 application, or AD9248BSTZ-65 equivalent, key selection considerations include dual-channel crosstalk immunity (>85 dB), flexible 1–2 V_p-p input range, offset binary/twos complement output format, and LQFP-64 package compatibility with evaluation board support.

Technical Context

The AD9248BSTZ-65 implements a multistage differential pipelined ADC architecture with output error correction logic to guarantee 14-bit accuracy and no missing codes across −40°C to +85°C. Each channel features independent sample-and-hold amplifiers with 500 MHz 3 dB bandwidth and configurable reference modes (shared or independent).

Dual single-ended clock inputs (CLK_A/CLK_B) drive conversion cycles, while the integrated duty cycle stabilizer (DCS) maintains performance over wide clock duty cycle variation. Digital outputs are CMOS-compatible, support data multiplexing via MUX_SELECT, and include out-of-range indicators (OTR_A/OTR_B) for overflow detection.

Key Specifications

Pinout & Package

The AD9248BSTZ-65 is housed in a Pb-free, 64-lead LQFP (Leadless Quad Flat Package) with exposed pad connected to AGND. Pin pitch is 0.5 mm; body size is 10 mm × 10 mm × 1.4 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel, 14-bit ADC applications.

Compared with AD9248BCPZ-65, AD9248BSTZ-65 offers easier hand-soldering and legacy board compatibility; compared with AD9238BSTZ-65, it delivers +2 bits resolution and +5.5 dB SFDR-critical for wideband communication and medical imaging where signal integrity is non-negotiable.

Availability

AD9248BSTZ-65 is available at Aetrix Electronics and suitable for ultrasound equipment, IF sampling receivers, and handheld test instrumentation requiring stable component supply and long-term industrial temperature support (−40°C to +85°C).

Supply support for AD9248BSTZ-65 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, headquartered in Norwood, MA, with design centers worldwide.

The AD9248 product line delivers high-speed, high-resolution dual ADCs optimized for communications infrastructure, medical imaging, and portable instrumentation-emphasizing low power, small footprint, and robust analog front-end integration.

FAQ

What is the maximum analog input frequency supported by the AD9248BSTZ-65?

The AD9248BSTZ-65 features a 500 MHz 3 dB analog input bandwidth and is specified for IF sampling applications up to 100 MHz input frequency. At f_IN = 100 MHz, it achieves SNR = 69.0 dB and SFDR = 75.0 dBc, enabling undersampling of bandpass signals into the first Nyquist zone. Performance remains usable beyond 100 MHz depending on system-level filtering and clock jitter constraints. The AD9248BSTZ-65 datasheet confirms this behavior in Table 2 and Figure 7.

Does the AD9248BSTZ-65 require an external reference voltage?

No, the AD9248BSTZ-65 includes an integrated 1.0 V reference with ±35 mV output error over temperature. It also supports external reference operation via the VREF and SENSE pins for improved accuracy or custom reference levels. In internal reference mode, REFT_A/REFB_A and REFT_B/REFB_B are internally biased; in external mode, those pins become differential reference inputs. This flexibility is documented in the General Description and Reference Circuitry sections of the AD9248BSTZ-65 datasheet.

How does the clock duty cycle stabilizer (DCS) function in the AD9248BSTZ-65?

The DCS circuit in the AD9248BSTZ-65 actively corrects for clock duty cycle asymmetry by generating an internal 50% duty cycle clock derived from the input CLK_A or CLK_B. When enabled (DCS pin high), it maintains ADC performance-including SNR and SFDR-across input duty cycles from 30% to 70%. This eliminates the need for external clock conditioning circuits and relaxes layout constraints on clock distribution. The AD9248BSTZ-65 functional block diagram and Figure 24 confirm its integration and operation.

Can both channels of the AD9248BSTZ-65 operate independently with different sampling rates?

No-the AD9248BSTZ-65 requires identical clock frequencies on CLK_A and CLK_B for synchronous dual-channel operation. Its architecture uses a shared pipeline clock domain; asynchronous clocking is not supported. However, each channel can be independently powered down (via PWDN_A/PWDN_B) or disabled via OEB_A/OEB_B, allowing time-multiplexed use of one channel while the other remains idle. This constraint is explicitly stated in the AC Specifications table and Timing Diagram (Figure 2) of the AD9248BSTZ-65 datasheet.

What is the purpose of the SHARED_REF pin on the AD9248BSTZ-65?

The SHARED_REF pin configures reference topology: logic high selects shared reference mode (REFT_A/REFB_A and REFT_B/REFB_B tied internally), minimizing gain mismatch between channels to ±0.01% FSR; logic low enables independent reference mode for maximum channel isolation. This setting directly impacts matching specifications-gain error matching improves from ±0.07% to ±0.01% FSR-making SHARED_REF critical for coherent dual-channel applications like I/Q demodulation. The AD9248BSTZ-65 Pin Function Descriptions (Table 6) and Matching Characteristics table validate this behavior.