Analog Devices Inc. AD9261BCPZ-10

Overview

AD9261BCPZ-10 from Analog Devices is a single-channel, 16-bit continuous-time sigma-delta analog-to-digital converter (ADC) optimized for high-dynamic-range data acquisition in 10 MHz input bandwidth applications. It delivers 83 dB SNR and 87 dBc SFDR at 2.4 MHz input, operates on 1.8 V analog supply with 340 mW power consumption, and supports selectable 2.5/5/10 MHz decimation filter bandwidths - used in medical imaging front-ends where precision low-noise digitization of ultrasound or MRI sensor signals is required.

For engineers reviewing the AD9261BCPZ-10 datasheet, AD9261BCPZ-10 pinout, AD9261BCPZ-10 application, or AD9261BCPZ-10 equivalent, key selection considerations include its resistive 1 kΩ differential input impedance, integrated PLL clock multiplier enabling 640 MHz internal modulator clock, 30–160 MSPS programmable output data rate, and support for offset binary/Gray/twos complement output formats with DCO timing reference.

Technical Context

The AD9261BCPZ-10 employs a fifth-order continuous-time Σ-Δ modulator with 32× oversampling, eliminating external anti-aliasing filters by inherently shaping alias energy out-of-band. Its loop filter transfer function (LF(f)) combines with discrete-time quantization noise transfer function (NTF(f)) to suppress aliases across all Nyquist zones while preserving signal integrity within the selected 2.5/5/10 MHz passband.

Digital processing includes on-chip decimation filtering, sample rate conversion, and serial SPI configuration. The ADC accepts differential analog inputs (VIN+/VIN−), supports external or PLL-generated clocks (CLK+/CLK−), and provides synchronous CMOS digital outputs (D0–D15) with programmable DRVDD (1.8–3.3 V) and data clock output (DCO) for timing-critical interfacing.

Key Specifications

Pinout & Package

The AD9261BCPZ-10 is housed in a 48-lead LFCSP (CP-48-9) package with exposed thermal pad (EPAD) soldered to analog ground plane for optimal thermal dissipation and EMI suppression.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution sigma-delta ADC applications.

Compared with AD9262BCPZ-10 and ADS127L11IRHBT, the AD9261BCPZ-10 uniquely balances 16-bit resolution, 10 MHz analog bandwidth, and 30–160 MSPS output flexibility in a single-channel LFCSP package - making it the preferred choice for wideband, moderate-speed, space-constrained data acquisition systems requiring minimal external components.

Availability

AD9261BCPZ-10 is available at Aetrix Electronics and suitable for medical imaging, automated test equipment, and industrial instrumentation requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for AD9261BCPZ-10 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, serving industrial, communications, automotive, and healthcare markets with precision data conversion and signal conditioning solutions.

The AD9261BCPZ-10 belongs to Analog Devices' high-speed continuous-time sigma-delta ADC product line, designed specifically for wideband, low-power, high-dynamic-range digitization in applications where traditional discrete-time ADCs require complex anti-aliasing filtering.

FAQ

What is the maximum input frequency supported by the AD9261BCPZ-10?

The AD9261BCPZ-10 supports an analog input bandwidth of 10 MHz, meaning it can accurately digitize signals up to 10 MHz before significant SNR degradation occurs. This is confirmed in the DC Specifications table (Page 3) and verified in Figure 17 (SNR/SFDR vs. Input Frequency), where performance remains stable up to 10 MHz at 83 dB SNR and >87 dBc SFDR. The device's continuous-time architecture inherently suppresses aliases beyond this point.

Does the AD9261BCPZ-10 require an external anti-aliasing filter?

No, the AD9261BCPZ-10 does not require an external anti-aliasing filter due to its continuous-time sigma-delta architecture. As explained in the "Analog Input Considerations" section (Page 14), alias rejection is inherent: the loop filter transfer function (LF(f)) and quantization noise transfer function (NTF(f)) jointly suppress aliases across all Nyquist zones. This eliminates external filter components, reducing BOM cost and board area.

What are the supported digital output formats for the AD9261BCPZ-10?

The AD9261BCPZ-10 supports three programmable digital output formats: offset binary, Gray code, and twos complement - configured via SPI register writes. This is explicitly stated in the "Features" section (Page 1) and detailed in the "Digital Outputs" subsection (Page 21). Format selection allows seamless integration with various FPGA logic families and DSP architectures without external translation logic.

How is the internal voltage reference configured on the AD9261BCPZ-10?

The AD9261BCPZ-10 features an unbuffered 0.5 V internal voltage reference (VREF) with a 10 kΩ series resistance. It must be decoupled using a 10 µF capacitor to minimize noise, as specified in Figure 39 and the "Voltage Reference" section (Page 15). The reference drives a current loop that develops AVDD − 0.5 V across the 500 Ω input resistors, establishing proper common-mode bias for VIN+/VIN−.

What is the purpose of the PLL_LOCKED pin on the AD9261BCPZ-10?

The PLL_LOCKED pin (Pin 7) is an open-drain output that asserts high when the on-chip integer-N PLL achieves frequency lock. As defined in Table 8 (Page 8), it provides hardware status feedback to system controllers - enabling safe initialization sequences before enabling data capture. This prevents corrupted samples during PLL startup and is essential for deterministic timing in automated test systems.