AD7890BNZ-2

ADCs/DACs - Special Purpose Overview

The AD7890BNZ-2 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, this B-version device supports a unipolar input range of 0 V to 2.5 V with straight binary output coding. Key electrical parameters include a maximum conversion time of 5.9 μs, typical power dissipation of 30 mW in normal mode, and standby power consumption of 75 μW. The unit features a high-speed serial interface and operates within a temperature range of -40°C to +85°C.

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 with external reference input capability
• High-speed bidirectional serial interface compatible with microcontrollers and DSPs
• Low-power operation: 30 mW typical (normal mode) and 75 μW typical (standby mode)

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 standby current
• Automotive test and measurement applications

ADCs/DACs - Special Purpose Procurement Notes

Verify the suffix 'B' confirms the commercial temperature grade (-40°C to +85°C) and the '-2' indicates the 0 V to 2.5 V input range. Confirm package availability matches the required footprint, typically PDIP-24 or SOIC-24. Check RoHS compliance status as manufacturing sites may vary. Ensure ordering quantities align with tube or reel packaging options provided by distributors.

ADCs/DACs - Special Purpose Selection Notes

Select the AD7890BNZ-2 when a unipolar 0 V to 2.5 V input range is required. Choose the 'A' version for extended industrial temperatures if operating conditions exceed +85°C. Consider the AD7890-10 variant if bipolar ±10 V inputs are necessary. Verify that the serial interface timing meets the host controller's clock specifications, particularly regarding self-clocking versus external clocking modes.

ADCs/DACs - Special Purpose Part Context

The AD7890 belongs to Analog Devices' specialized data acquisition family, designed to reduce board space and component count. The 'BNZ' designation typically refers to the plastic dual-in-line package (PDIP) variant with lead-free composition. This monolithic approach simplifies design by eliminating external references and track/hold amplifiers commonly found in discrete solutions.

ADCs/DACs - Special Purpose Replacement Considerations

Direct pin-compatible replacements within the same series include AD7890ANZ-2 (commercial temp, PDIP) and AD7890ARZ-2 (commercial temp, SOIC). For extended temperature ranges, consider AD7890SQ-2 variants. Cross-family upgrades may require schematic changes due to different pinouts or interface protocols.