AD7890AN-4

ADCs/DACs - Special Purpose Overview

The AD7890AN-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 analog input ranges of 0 V to 4.096 V. The device features a high-speed serial interface with a maximum conversion time of 5.9 μs. DC accuracy specifications include ±1 LSB differential nonlinearity and ±2.5 LSB gain error. Dynamic performance includes a signal-to-noise ratio of 70 dB minimum. Power consumption is 50 mW maximum in normal mode.

ADCs/DACs - Special Purpose Feature Summary

• Integrated 8-channel multiplexer with separate access to MUX OUT for external antialiasing filtering
• High-speed serial interface compatible with microcontrollers and DSP processors
• On-chip 2.5 V voltage reference with external reference input capability
• Low power operation: 50 mW max in normal mode, 75 μW typ in standby

ADCs/DACs - Special Purpose Applications

• Industrial process control systems requiring multi-channel signal acquisition
• Data acquisition modules for factory automation
• Instrumentation systems utilizing serial communication protocols

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific suffix 'AN' indicates the commercial temperature range (-40°C to +85°C) and PDIP-24 package. Confirm the '-4' suffix corresponds to the 0 V to 4.096 V input range. Check current availability status as legacy components may have limited stock or obsolescence notices from Analog Devices.

ADCs/DACs - Special Purpose Selection Notes

Select the AD7890AN-4 when an 8-channel solution with a unipolar 0 V to 4.096 V input range is required. Ensure the system clock frequency does not exceed 2.5 MHz for specified performance. Verify that the serial interface timing matches the host controller's capabilities, particularly regarding self-clocking versus external clocking modes.

ADCs/DACs - Special Purpose Part Context

The AD7890 belongs to a family of monolithic data acquisition systems including variants with different input ranges (AD7890-2, AD7890-10) and temperature grades (A, B, S versions). The AN designation typically refers to the plastic DIP package variant within the commercial temperature range.

ADCs/DACs - Special Purpose Replacement Considerations

Direct pin-compatible replacements within the same family include AD7890ARZ-4 (SOIC package) or AD7890BRZ-4 (industrial temperature range). Cross-family replacements require verification of pinout compatibility and software register mapping.