AD9218BSTZ-65

Overview

The AD9218BSTZ-65 is a dual-channel, 10-bit pipeline analog-to-digital converter manufactured by Analog Devices Inc. It supports a maximum sampling rate of 65 MSPS and operates on a single 3.0 V supply (2.7 V to 3.6 V). Each channel features an integrated track-and-hold circuit and a 300 MHz full-power analog bandwidth. The device provides user-selectable 1 Vp-p or 2 Vp-p differential input ranges and includes an internal 1.24 V voltage reference. Digital outputs are TTL/CMOS compatible with selectable offset binary or two's complement formats. It is housed in a 48-lead LQFP package rated for industrial temperatures from -40°C to +85°C.

Feature Summary

• Dual-channel architecture with independent operation and low inter-channel crosstalk.
• Integrated track-and-hold circuits and internal voltage reference simplify system design.
• Flexible digital output interface supporting multiple logic levels and data encoding formats.
• Pin-compatible upgrade path from legacy 8-bit devices.

Applications

• I and Q communications demodulators
• Low-cost digital oscilloscopes
• Hand-held scopemeters
• Battery-powered instruments
• Ultrasound equipment

Procurement Notes

Verify the specific speed grade suffix matches the required sampling rate. Confirm that the ordering code corresponds to the standard tape-and-reel or tray packaging options available for this component series. Ensure the manufacturer source is authorized to guarantee device authenticity and traceability.

Selection Notes

Select this model when a 65 MSPS sampling rate is sufficient for the application bandwidth. Consider the 2 Vp-p input range option if higher dynamic range is needed compared to the 1 Vp-p configuration. Evaluate power consumption requirements as dissipation scales with the encode rate and load capacitance.

Part Context

This component belongs to the AD9218 family of dual 10-bit ADCs, which also includes variants rated for 40 MSPS, 80 MSPS, and 105 MSPS. All members share identical pinouts and functional blocks, allowing for direct substitution based on bandwidth needs without PCB redesign.

Replacement Considerations

The AD9218BSTZ-40, AD9218BSTZ-80, and AD9218BSTZ-105 are pin-compatible alternatives within the same family. Verify that the alternative speed grade meets the minimum sampling requirements of the target system.

FAQ

How does the DFS/GAIN pin affect the analog input range?

Connecting DFS/GAIN to ground enables the 1 Vp-p input range with offset binary output. Connecting it to VREF enables the 2 Vp-p input range with two's complement output. Leaving it floating defaults to the 2 Vp-p range with offset binary output.

What is the pipeline delay for the AD9218?

The AD9218 has a fixed pipeline delay of five clock cycles between the encode command and the availability of valid digital output data.

Can the AD9218 operate with a single-ended input signal?

Yes, although differential drive is recommended for optimal performance. The device can accept single-ended signals, but impedance matching at the inputs should be maintained to minimize distortion.