AD7825BRUZ-REEL

Overview

The AD7825BRUZ-REEL is a high-speed, 4-channel, 8-bit analog-to-digital converter manufactured by Analog Devices. It features a maximum throughput of 2 MSPS and utilizes a half-flash architecture with an on-chip track-and-hold amplifier. The device operates from a single supply voltage ranging from 3 V ± 10% to 5 V ± 10%. Key electrical parameters include a signal-to-noise ratio of 48 dB minimum, integral nonlinearity of ±0.75 LSB, and differential nonlinearity of ±0.75 LSB. Power consumption is typically 24 mW during normal operation and drops to 0.2 μA in power-down mode.

Feature Summary

• Integrated 2.5 V reference and track-and-hold amplifier for simplified system design
• Automatic power-down functionality at the end of conversion to minimize energy usage
• Flexible parallel interface compatible with microprocessors and DSPs
• Input offset adjustment capability via the VMID pin

Applications

• Data acquisition systems
• DSP front ends
• Disk drives
• Mobile communication systems
• Subsampling applications

Procurement Notes

Verify the specific ordering suffix against manufacturer documentation to confirm packaging type and reel specifications. Ensure compatibility with required operating temperature ranges and supply voltage constraints before finalizing procurement decisions.

Selection Notes

Select this component when four single-ended channels are required alongside high-speed sampling capabilities. Consider the half-flash architecture for fast conversion times and evaluate the need for input span adjustment using the VMID pin relative to system offset requirements.

Part Context

This part belongs to the AD7822/AD7825/AD7829 family of sampling ADCs. While sharing core architectural similarities, channel count distinguishes the AD7825 (4 channels) from the AD7822 (1 channel) and AD7829 (8 channels). All variants share identical conversion speeds and power characteristics.

Replacement Considerations

Direct functional substitutes within the same family include the AD7822 and AD7829, provided channel count differences are acceptable. Verify pinout compatibility and logic level requirements when considering cross-family replacements.

FAQ

How does the automatic power-down feature work?

The ADC checks the logic level on the CONVST pin at the end of a conversion. If CONVST is low, the device enters power-down mode automatically.

What is the default input voltage range?

With the VMID pin unconnected, the default input range is 0 V to 2.5 V for 5 V supplies and 0 V to 2 V for 3 V supplies.

Can the input span be adjusted?

Yes, applying a voltage to the VMID pin allows the user to center the input span anywhere within the AGND to VDD range.