AD7868AR

Specialized Overview

The AD7868AR is a complete 12-bit analog I/O system manufactured by Analog Devices Inc. in a 28-pin SOIC package. It integrates a successive approximation ADC with a track-and-hold amplifier and a DAC with an output buffer. The device operates from ±5 V supplies, providing an analog input/output range of ±3 V. Key electrical parameters include an 83 kHz throughput rate, 70 dB SNR for the A-version, and a typical power dissipation of 130 mW. Internal temperature-compensated 3 V buried Zener references support both converters.

Specialized Feature Summary

• Integrates a 12-bit ADC with track-and-hold and a 12-bit DAC with buffered output on a single chip.
• Features separate on-chip voltage references for precision biasing of both the ADC and DAC sections.
• Supports serial interfacing to DSP machines using standard control signals like CONVST and LDAC.

Specialized Applications

• Digital Signal Processing
• Speech Recognition and Synthesis
• Spectrum Analysis

Specialized Procurement Notes

Verify the specific revision level (A or B) regarding SNR accuracy when sourcing this component. Confirm that the 28-pin SOIC package matches the design footprint. Ensure supply voltages are strictly maintained within ±5% of nominal to meet specified performance characteristics. Check for ESD sensitivity precautions during handling.

Specialized Selection Notes

Select the AD7868AR when a compact 12-bit I/O solution is required for DSP applications. Choose this part over discrete components to minimize pin count and board space. Verify that the ±3 V input/output range aligns with system signal levels. Consider the internal reference stability if external buffering is not utilized.

Specialized Part Context

The AD7868 belongs to the LC2MOS family of complete analog I/O systems. It is functionally similar to the AD7869 but offers lower resolution. The 'AR' suffix indicates the 28-pin plastic SOIC package variant. This component serves as a self-contained interface between digital processors and analog signals.

Specialized Replacement Considerations

The AD7868BR is available as a higher-accuracy alternative with 72 dB SNR. For legacy DIP requirements, the AD7868AN is the corresponding package option. No direct cross-manufacturer equivalents are documented in the official datasheet.