AD7739BRUZ

Overview

The AD7739BRUZ is an 8-channel, 24-bit Sigma-Delta analog-to-digital converter (ADC) in a 24-lead TSSOP package. It features configurable single-ended or fully differential inputs with ranges of ±625 mV to ±2.5 V. The device supports a 3-wire serial interface compatible with SPI and DSPs, operating on a 5 V analog supply and 3 V or 5 V digital supply. Key specifications include 24-bit no missing codes, ±0.0015% integral nonlinearity, and per-channel system calibration. It operates within an industrial temperature range of –40°C to +105°C.

Feature Summary

• Configurable input architecture supporting eight single-ended or four fully differential channels.
• Integrated per-channel system calibration to minimize offset and gain errors.
• Programmable chopping mode for optimizing noise performance versus throughput rate.
• Differential reference input with integrated no-reference detect capability.

Applications

• Process control systems
• Industrial instrumentation
• Multiplexing applications

Procurement Notes

Verify the specific suffix BRUZ corresponds to the 24-lead TSSOP package and industrial temperature grade (-40°C to +105°C). Confirm that the ordering part number matches the Rev. A datasheet requirements for Analog Devices Inc. components. Ensure compatibility with the required 5 V analog and 3 V/5 V digital supply voltages before procurement.

Selection Notes

Select this component when high channel count multiplexing is required alongside high resolution. The AD7739 offers faster channel switching compared to the AD7738 while maintaining 16-bit peak-to-peak resolution. Consider the AD7734 or AD7732 if fewer channels or different input voltage ranges are needed. Evaluate the chopping mode settings to balance between low noise and high data throughput based on application constraints.

Part Context

The AD7739 belongs to the AD773x family of high-throughput sigma-delta ADCs from Analog Devices. It shares architectural similarities with the AD7738, AD7734, and AD7732 but distinguishes itself through its specific combination of eight analog inputs and optimized switching speed. This family targets precision measurement applications requiring multiple channels without external multiplexers.

Replacement Considerations

The AD7738 is a similar device offering higher speed but with increased leakage current. The AD7734 provides four single-ended channels with extended overvoltage protection, while the AD7732 offers two fully differential channels. Verify pinout and register compatibility when substituting these family members.

FAQ

What is the maximum number of analog input channels supported by the AD7739?

The AD7739 supports up to eight single-ended analog input channels or four fully differential input channels.

How does the chopping feature affect the AD7739's performance?

Enabling chopping reduces offset drift and improves low-frequency noise performance at lower output data rates. Disabling chopping allows for faster conversion times and higher throughput rates.

What is the function of the REFIN(+) and REFIN(-) pins?

These pins serve as the differential reference input terminals. The device includes a no-reference detect capability that triggers if the reference voltage falls below a specified threshold.