AD7890AR-4

ADCs/DACs - Special Purpose Overview

The AD7890AR-4 is an 8-channel, 12-bit data acquisition system fabricated in LC2MOS technology. It integrates a multiplexer, track/hold amplifier, ADC, and 2.5 V reference on a single chip. Operating from a single 5 V supply, it accepts unipolar analog input voltages ranging from 0 V to 4.096 V. The device features a high-speed serial interface with a maximum conversion time of 5.9 μs. Power consumption is typically 30 mW in normal mode and drops to 75 μW in standby. It is housed in a 24-lead SOIC package.

ADCs/DACs - Special Purpose Feature Summary

• Integrated 8-channel multiplexer with separate MUX OUT access for external antialiasing filtering
• On-chip 2.5 V voltage reference and track/hold amplifier
• High-speed bidirectional serial interface compatible with microcontrollers and DSPs
• Low power operation: 50 mW maximum in normal mode, 75 μW typical in standby

ADCs/DACs - Special Purpose Applications

• Industrial process control systems requiring multi-channel signal acquisition
• Data logging equipment with moderate speed requirements
• Battery-powered instrumentation utilizing low-power standby modes
• Automotive sensor interfaces operating within specified temperature ranges

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific suffix 'AR-4' against official Analog Devices documentation to confirm the SOIC_W package and 0 V to 4.096 V input range. Ensure compatibility with existing board layouts for 24-lead SOIC packages. Check for moisture sensitivity levels if reflow soldering is required. Confirm that the 5 V logic levels match the host system's digital interface requirements.

ADCs/DACs - Special Purpose Selection Notes

Select the AD7890AR-4 when an 8-channel solution with a 0 V to 4.096 V input range is needed. Choose this part over the AD7890-10 if bipolar inputs are not required. Consider the AD7890-2 if a lower 0 V to 2.5 V range suffices. Verify that the 5.9 μs conversion time meets the system's sampling rate needs. Ensure the serial interface timing aligns with the host processor's capabilities.

ADCs/DACs - Special Purpose Part Context

The AD7890 belongs to a family of monolithic data acquisition systems by Analog Devices. Variants include the AD7890-10 for ±10 V inputs and AD7890-2 for 0–2.5 V inputs. The 'A' version denotes a commercial temperature range (-40°C to +85°C). The 'R' indicates the SOIC package. The '4' specifies the unipolar input range configuration.

ADCs/DACs - Special Purpose Replacement Considerations

Direct pin-compatible replacements within the same family include AD7890ARZ-10 (±10 V range) and AD7890ARZ-2 (0–2.5 V range). Verify that the input voltage range of the substitute matches the application requirements. Check if updated revisions offer improved specifications or packaging options.