AD7765BRUZ

Overview

The AD7765BRUZ is a high-performance, single-channel, 24-bit Sigma-Delta analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates with a maximum output data rate of 156 kSPS and achieves a dynamic range of 112 dB at this speed, or 115 dB at 78.125 kSPS. The device features pin-selectable decimation rates of 128× and 256×, an integrated fully differential amplifier for signal buffering, and an on-chip reference buffer. It utilizes a flexible serial peripheral interface (SPI), supports daisy-chaining, and includes a full-band low-pass finite impulse response (FIR) filter. The component is housed in a 28-lead TSSOP package and functions within an industrial temperature range of −40°C to +85°C.

Feature Summary

• Integrates a fully differential amplifier and reference buffer to minimize external signal conditioning requirements.
• Features a full-band digital FIR filter that provides stop-band attenuation at the Nyquist frequency to prevent aliasing.
• Includes an overrange alert pin and internal registers for gain correction and status monitoring.
• Supports multiple power modes, including a low-power option that reduces dissipation without affecting bandwidth.

Applications

• Data acquisition systems
• Vibration analysis
• Instrumentation

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to ensure correct packaging and tape-and-reel specifications. Confirm that the voltage supply requirements align with the intended application environment. Check for any recent revision changes in the datasheet that may affect pin compatibility or electrical characteristics before finalizing procurement orders.

Selection Notes

Select the AD7765BRUZ when high-resolution, high-speed data conversion is required for AC signals alongside DC data. Ensure the system design accommodates the dual-voltage supply requirement (2.5 V and 5 V) specified for optimal performance. Consider the available decimation rates and the need for synchronization across multiple devices if building a multi-channel architecture.

Part Context

The AD7765 belongs to the AD776x family of high-performance ADCs from Analog Devices. Related devices include the AD7760, AD7762, AD7763, and AD7764, which offer varying speeds and output interfaces. The AD7766 and AD7767 are lower-power alternatives within the same series. This component is distinct for its combination of high speed, high resolution, and integrated analog front-end buffers.

Replacement Considerations

Direct replacements within the same package and functionality include the AD7760, AD7762, AD7763, and AD7764. For lower power applications, consider the AD7766 or AD7767. Verify pinout compatibility and register mapping when substituting these related parts.

FAQ

How does the AD7765 handle anti-aliasing?

The AD7765 incorporates a full-band low-pass finite impulse response (FIR) filter that achieves stop-band attenuation at the Nyquist frequency, reducing the need for external anti-alias filters.

What is the function of the SYNC pin?

The SYNC pin allows for the synchronization of multiple AD7765 devices in a system by resetting the internal filter and ensuring simultaneous data output.

Can the AD7765 operate in a low-power mode?

Yes, the AD7765 offers a low-power mode that significantly reduces power dissipation without decreasing the output data rate or available input bandwidth.