Analog Devices Inc. AD9218BST-80

Overview

AD9218BST-80 from Analog Devices is a dual 10-bit, 80 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 57 dB SNR at 41 MHz input and –75 dBc crosstalk between channels - deployed in low-cost digital oscilloscopes and I/Q communications receivers.

For engineers reviewing the AD9218BST-80 datasheet, AD9218BST-80 pinout, AD9218BST-80 application, or AD9218BST-80 equivalent, this page delivers verified specifications, validated pin functions, confirmed industrial-temperature operation (–40°C to +85°C), exact LQFP-48 package mapping, and two rigorously cross-checked alternative ADCs for dual-channel sampling systems requiring ≥80 MSPS throughput and ≤1 V_p-p differential input range.

Technical Context

The AD9218BST-80 implements a bit-per-stage pipeline architecture with five-cycle latency, supporting independent channel operation and user-selectable twos complement or offset binary output formats. Its differential analog inputs feature 300 MHz full-power bandwidth and self-biasing to V_D/3, enabling flexible ac- or dc-coupled drive configurations.

Timing control is managed via TTL/CMOS-compatible ENCA/ENCB clocks, with S1/S2 pins configuring power-down modes (both or Channel B only) or data alignment (½-cycle skew for synchronized dual-clock operation). The internal 1.24 V reference (REFOUT) drives both channels and supports ±5% adjustment without performance degradation.

Key Specifications

Pinout & Package

AD9218BST-80 is housed in a 48-lead low-profile quad flat package (LQFP), 7 mm × 7 mm, with exposed pad, rated for industrial temperature operation (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel, 10-bit, ≥80 MSPS analog-to-digital conversion applications.

Compared with AD9218BST-105, the AD9218BST-80 trades 25 MSPS headroom for 40 mW lower power and identical pin compatibility; versus AD9288BST-80, it delivers +2 bits resolution and +8 dB SNR at no PCB change, making it the precision upgrade path within the same footprint.

Availability

AD9218BST-80 is available at Aetrix Electronics and suitable for low-cost digital oscilloscopes, I/Q communications receivers, and ultrasound equipment requiring stable component supply, long-term industrial temperature qualification, and guaranteed dual-channel timing coherence.

Supply support for AD9218BST-80 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, automotive, communications, and healthcare markets since 1965.

The AD9218 product line delivers dual-channel, high-speed ADCs optimized for direct IF sampling and portable test instrumentation - designed to replace discrete ADC + reference + driver solutions with a single monolithic IC.

FAQ

What is the maximum analog input frequency supported by the AD9218BST-80?

The AD9218BST-80 features a 300 MHz full-power analog bandwidth, meaning it maintains specified dynamic performance (e.g., SNR, SFDR) for input signals up to 300 MHz. At its 80 MSPS sampling rate, the Nyquist frequency is 40 MHz; however, the device supports undersampling applications where RF signals above Nyquist are aliased into baseband with preserved integrity - confirmed by Figure 15 (FFT at 39 MHz input) and Table 3 AC specifications tested at Nyquist-equivalent frequencies.

Does the AD9218BST-80 require an external reference voltage?

No, the AD9218BST-80 does not require an external reference voltage. It integrates a precision 1.24 V internal reference (REFOUT) that can directly drive REFINA and REFINB pins to establish a stable 1 V_p-p differential input range. External references are optional for custom scaling, but the internal reference is fully characterized and supports all guaranteed specifications across the industrial temperature range.

Can the AD9218BST-80 operate with separate analog and digital supply voltages?

Yes, the AD9218BST-80 uses dedicated supply pins: VD (analog core, 2.7–3.6 V) and VDD (digital outputs, 2.5–3.6 V). This separation allows independent optimization - for example, powering the analog section from a clean 3.0 V LDO while interfacing outputs to a 2.5 V FPGA bank. Both supplies must remain within their respective ranges, and decoupling capacitors are required per datasheet Figure 20 layout guidelines.

How is channel synchronization handled in the AD9218BST-80?

The AD9218BST-80 supports precise channel synchronization via its S1/S2 control pins and dual clock inputs (ENCA/ENCB). With S1=1 and S2=1, the data align mode delays Channel B output by ½ clock cycle, allowing both channels' data to appear aligned on the rising edge of ENCA - essential for coherent I/Q sampling. This behavior is validated in Figure 4 timing diagram and Table 7 user-select mode definitions.

Is the AD9218BST-80 pin-compatible with other members of the AD9218 family?

Yes, all AD9218 speed grades - including AD9218BST-40, AD9218BST-65, AD9218BST-80, and AD9218BST-105 - share identical LQFP-48 pinout, package dimensions, and footprint. This enables hardware reuse across performance tiers; only the speed grade suffix changes, and system firmware must be updated to match the selected encode rate and associated timing constraints.