AD7934BRU-REEL

Overview

The AD7934BRU-REEL is a 12-bit, high-speed successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It features four analog input channels with an integrated channel sequencer and operates from a single 2.7 V to 5.25 V power supply. The device achieves throughput rates up to 1.5 MSPS with low power consumption of 6 mW at 3 V and 13.5 mW at 5 V. It includes an accurate on-chip 2.5 V reference and supports single-ended, fully differential, or pseudo-differential inputs via software configuration. The parallel interface allows direct connection to 3 V or 5 V processors through the VDRIVE function.

Feature Summary

• Four analog input channels with a programmable channel sequencer for automated conversion sequences.
• Software-selectable analog input configurations supporting single-ended, fully differential, and pseudo-differential modes.
• Integrated precise 2.5 V internal voltage reference with low temperature coefficient.
• High-speed parallel interface with word/byte transfer modes and independent logic supply (VDRIVE).

Applications

• Industrial process control systems requiring multi-channel data acquisition.
• Portable instrumentation utilizing battery-powered single-supply operation.
• Medical equipment needing low-noise signal conversion with flexible input ranges.

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current datasheet to confirm package type and tape/reel specifications. Ensure compatibility with system voltage levels and clock requirements before integration. Cross-reference part numbers with official distributor catalogs to avoid counterfeit components.

Selection Notes

Select this component when 12-bit resolution and 1.5 MSPS throughput are required for multi-channel applications. Consider the AD7933 if 10-bit resolution suffices for lower cost. Evaluate power constraints as the device offers autostandby and full shutdown modes for energy efficiency in portable designs.

Part Context

This part belongs to the AD7933/AD7934 family of 10-bit and 12-bit SAR ADCs. It shares architectural similarities with the AD7938/AD7939 series but differs in channel count and interface options. The BRU suffix typically denotes a specific thermal and packaging variant within the Analog Devices portfolio.

Replacement Considerations

The AD7933BRU serves as a 10-bit alternative within the same package. For higher channel counts, consider the AD7938 or AD7939 series. Verify pinout compatibility and register settings when substituting with other SAR ADC families.

FAQ

How does the VDRIVE pin affect the digital interface?

The VDRIVE pin sets the logic voltage level for the parallel interface, allowing it to operate independently of the analog supply (VDD). This enables direct interfacing with 3 V or 5 V microprocessors without level shifting.

What is the maximum input frequency the ADC can handle?

The AD7934 features a differential track-and-hold amplifier capable of handling input frequencies up to 50 MHz, ensuring accurate sampling even at high speeds.

Can the internal reference be bypassed?

Yes, the VREFIN/VREFOUT pin can be overdriven by an external reference voltage ranging from 0.1 V to VDD to replace the internal 2.5 V reference.