AD7874ARZ

ADCs/DACs - Special Purpose Overview

The AD7874ARZ is a four-channel, 12-bit simultaneous sampling data acquisition system fabricated in LC2MOS technology. It integrates four track/hold amplifiers, a successive approximation ADC, an internal 3 V reference, and an on-chip clock. The device operates with ±5 V supplies and accepts analog input voltages within the ±10 V range. Key electrical specifications include a maximum conversion time of 8 μs per channel, a total throughput rate of 29 kHz for all channels, and a typical signal-to-noise ratio of 70 dB at a 10 kHz input frequency. The component is housed in a 28-pin SOIC package.

ADCs/DACs - Special Purpose Feature Summary

• Four independent on-chip track/hold amplifiers enable true simultaneous sampling across all channels.
• Tight aperture delay matching of less than 4 ns preserves relative phase information between channels.
• Integrated laser-trimmed 3 V buried Zener reference with buffered output capability.
• Fast microprocessor interface supporting direct connection to 16-bit processors via three-state TTL outputs.

ADCs/DACs - Special Purpose Applications

• Phased-array sonar systems requiring precise phase alignment.
• AC motor controllers utilizing multi-channel feedback.
• Adaptive filter implementations.
• Digital signal processing architectures.

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific suffix against the Ordering Guide to confirm temperature range and accuracy class. The 'A' version denotes commercial operation from -40°C to +85°C with ±1 LSB relative accuracy. Confirm that the package designation matches the required footprint, as the ARZ suffix indicates a plastic SOIC variant. Ensure supply voltage decoupling meets the specified requirements for stable performance.

ADCs/DACs - Special Purpose Selection Notes

Select the AD7874 when simultaneous sampling of multiple signals is critical to maintain phase coherence. The device requires dual ±5 V power supplies and a 3 V reference voltage applied to REF IN or generated internally via REF OUT. Consider the 29 kHz aggregate sample rate and 8 μs conversion time when designing system timing constraints. Verify that the input signal amplitude remains within the ±10 V limit to prevent damage or clipping.

ADCs/DACs - Special Purpose Part Context

The AD7874 belongs to Analog Devices' LC2MOS family of high-speed data acquisition components. Unlike multiplexed ADCs that share a single track/hold amplifier, this part utilizes discrete amplifiers for each channel. This architectural distinction eliminates inter-channel crosstalk and aperture delay skew inherent in shared-amp designs, making it suitable for applications where signal timing relationships are paramount.

ADCs/DACs - Special Purpose Replacement Considerations

Public confirmed substitute part numbers: None identified in verified documentation.