Analog Devices Inc. AD9218BSTZ-40

Overview

AD9218BSTZ-40 from Analog Devices is a dual 10-bit, 40 MSPS analog-to-digital converter with on-chip track-and-hold and internal reference, operating from a single 3.0 V supply (2.7–3.6 V), delivering 59 dB SNR at 10.3 MHz input and –75 dBc inter-channel crosstalk-used in handheld scopemeters and low-cost digital oscilloscopes.

For engineers reviewing the AD9218BSTZ-40 datasheet, AD9218BSTZ-40 pinout, AD9218BSTZ-40 application, or AD9218BSTZ-40 equivalent, key selection criteria include dual-channel sampling rate (40 MSPS), 1 V_p-p or 2 V_p-p input range flexibility, power-down mode for single-channel operation, twos complement/offset binary output format, and LQFP-48 package compatibility with AD9288.

Technical Context

The AD9218BSTZ-40 implements a bit-per-stage pipeline ADC architecture with differential analog inputs, independent channel operation, and five-cycle pipeline latency. Each channel features a dedicated encode input (ENCA/ENCB), configurable gain via DFS/GAIN pin, and user-selectable data alignment or power-down modes through S1/S2 control pins.

It integrates an on-chip 1.24 V reference (REFOUT), supports external reference via REFINA/REFINB, and delivers TTL/CMOS-compatible digital outputs powered from a separate VDD rail (2.5–3.6 V). The analog input stage has 300 MHz bandwidth and self-biases to V_D/3 common-mode voltage.

Key Specifications

Pinout & Package

The AD9218BSTZ-40 is housed in a 48-lead LQFP (7 mm × 7 mm) package rated for industrial temperature range (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9218BSTZ-65 and AD9288BSTZ-40, the AD9218BSTZ-40 uniquely balances 10-bit resolution, 40 MSPS speed, and 275 mW/channel power-making it optimal for portable instrumentation where precision and battery life are co-constrained.

Availability

AD9218BSTZ-40 is available at Aetrix Electronics and suitable for battery-powered instruments, handheld scopemeters, and low-cost digital oscilloscopes requiring stable component supply and long-term industrial temperature support.

Supply support for AD9218BSTZ-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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, and healthcare markets since 1965.

The AD9218 product line delivers dual-channel, high-speed ADCs optimized for portable test equipment and communications receivers-designed to replace discrete ADC+driver+reference subsystems with monolithic integration and guaranteed AC performance across temperature.

FAQ

What is the maximum analog input frequency supported by the AD9218BSTZ-40?

The AD9218BSTZ-40 has a 300 MHz analog bandwidth, meaning it maintains full-scale response up to 300 MHz. However, its 40 MSPS sampling rate limits the Nyquist frequency to 20 MHz; signals above 20 MHz will alias unless filtered. For non-aliased acquisition, the practical maximum input frequency is 20 MHz, though the device can accept higher-frequency signals for undersampled IF applications with appropriate anti-alias filtering.

Does the AD9218BSTZ-40 require an external reference voltage?

No, the AD9218BSTZ-40 does not require an external reference voltage. It includes an on-chip 1.24 V reference (REFOUT) that can be directly connected to REFINA and REFINB pins to establish a stable 1.25 V reference for both channels. External references are optional and only needed when precise gain calibration or custom full-scale ranges beyond ±5% adjustment are required.

How is channel synchronization achieved in the AD9218BSTZ-40?

Channel synchronization in the AD9218BSTZ-40 is achieved via independent ENCA and ENCB clock inputs and the S1/S2 control pins. When S1=1 and S2=1, the data align mode enables Channel B output data to be delayed by ½ clock cycle relative to Channel A, allowing both channels' data to be captured on the same rising edge of Clock A. This eliminates inter-channel timing skew in FPGA or ASIC interfaces.

What power supply configurations are supported by the AD9218BSTZ-40?

The AD9218BSTZ-40 supports a single 3.0 V supply (2.7–3.6 V) applied to both V_D (analog core) and V_DD (digital outputs). V_DD may be independently set to 2.5–3.6 V to interface with 2.5 V or 3.3 V logic families. No negative or auxiliary supplies are needed. Power-down mode reduces V_D current to 22 mA while placing digital outputs in high-impedance state.

Can the AD9218BSTZ-40 operate with single-ended analog inputs?

Yes, the AD9218BSTZ-40 can operate with single-ended analog inputs, though differential drive is recommended for optimal performance. When using single-ended inputs, one side (e.g., AINA) is driven with the signal while the complementary input (AINA) is tied to V_D/3 (1 V). This configuration degrades SNR by ~3–5 dB compared to differential operation but remains functional for lower-dynamic-range applications.