AD7720BRUZ-REEL

ADCs/DACs - Special Purpose Overview

The AD7720BRUZ is a 7th-order CMOS sigma-delta modulator in a 28-lead TSSOP package. It converts analog signals into a high-speed 1-bit data stream using a differential input range of 0 V to +2.5 V or ±1.25 V. Operating from a single +5 V supply, the device features an on-chip 2.5 V reference and supports master clock frequencies up to 12.5 MHz. Key static performance metrics include 16-bit resolution, ±1 LSB maximum differential nonlinearity, and ±2 LSB typical integral nonlinearity.

ADCs/DACs - Special Purpose Feature Summary

• 7th-order sigma-delta modulation architecture with 90 dB dynamic range
• Integrated 2.5 V voltage reference with external reference capability
• Differential input support for unipolar (0 V to 2.5 V) and bipolar (±1.25 V) modes
• Continuous sampling eliminates the need for external sample-and-hold circuits

ADCs/DACs - Special Purpose Applications

• High-resolution audio signal processing systems
• Precision industrial measurement instrumentation
• Vibration monitoring and control applications
• Medical equipment requiring accurate analog-to-digital conversion

ADCs/DACs - Special Purpose Procurement Notes

Verify the REEL suffix indicates tape-and-reel packaging rather than tube packaging. Confirm the B version temperature range (-40°C to +85°C) matches system requirements. Ensure the 28-lead TSSOP footprint aligns with PCB layout specifications before ordering.

ADCs/DACs - Special Purpose Selection Notes

Select this component when a high-speed bit-stream output is required for external digital filtering. The internal oscillator requires an external crystal or CMOS clock source. Designers must account for the switched-capacitor input impedance, which varies with the master clock frequency, when selecting driving amplifiers.

ADCs/DACs - Special Purpose Part Context

The AD7720 belongs to Analog Devices' family of sigma-delta modulators. It serves as the front-end converter for systems utilizing external decimation filters, such as those found in the AD7722. The BRUZ designation specifies the industrial temperature grade and surface-mount TSSOP-28 package configuration.

ADCs/DACs - Special Purpose Replacement Considerations

The AD7722 is a pin-compatible integrated solution that includes the digital filter. Verify interface compatibility if substituting with other sigma-delta modulators, as clocking and reset timing may differ.

ADCs/DACs - Special Purpose FAQ

How is the common-mode bias established for differential inputs?

In bipolar mode, the inputs are centered about a common-mode bias, typically 1.25 V. In unipolar mode, the range is 0 V to VREF.

What is the function of the MZERO and GC pins?

MZERO grounds the modulator inputs to measure offset error, while GC enables gain error calibration.

Can the AD7720 operate without an external clock?

No, it requires a master clock via XTAL1/MCLK, generated by an external crystal or CMOS signal.