AD7878KPZ

Overview

The AD7878KPZ is a complete 12-bit analog-to-digital converter featuring an integrated DSP interface with an 8-word FIFO memory. It operates on dual ±5 V supplies and accepts bipolar analog inputs within a ±3 V range. The device achieves a signal-to-noise ratio of 72 dB at a 10 kHz input frequency with a 100 kHz sampling rate. Key performance metrics include a maximum data access time of 41 ns, a typical power dissipation of 60 mW, and a conversion time of 7 μs. It utilizes Linear Compatible CMOS technology.

Feature Summary

• Integrates an 8-word first-in, first-out memory to reduce software overhead for digital signal processors.
• Features a versatile DSP interface with fast data access times compatible with high-speed microprocessors.
• Includes an on-chip track/hold amplifier, 3 V Zener reference, and status/control register.

Applications

• Digital Signal Processing
• Speech Recognition and Synthesis
• Spectrum Analysis
• High Speed Modems
• DSP Servo Control

Procurement Notes

Verify the specific grade suffix (K) against the manufacturer's ordering guide to confirm the temperature range and dynamic performance specifications. Ensure the PLCC-28 package variant matches the target PCB footprint requirements. Cross-reference the revision level of the datasheet to confirm pinout compatibility and absolute maximum ratings before finalizing procurement orders.

Selection Notes

Select this component when interfacing directly with DSPs such as the ADSP-2100 or TMS320 series due to its native FIFO architecture. Choose the K-grade version for commercial temperature ranges (0°C to +70°C) requiring 72 dB SNR. Consider the 41 ns access time for systems demanding minimal latency between conversion and data retrieval by the host processor.

Part Context

The AD7878 belongs to Analog Devices' LC2MOS family of complete ADCs designed for high-speed data acquisition. The KPZ designation indicates a Plastic Leaded Chip Carrier package with a commercial temperature rating. This part bridges the gap between traditional ADCs and DSPs by handling buffering internally, simplifying system design for audio and communication applications.

Replacement Considerations

The AD7878LP offers identical electrical characteristics but with a faster 41 ns data access time compared to the standard 57 ns found in other variants. For hermetic packaging requirements, the AD7878QP serves as a ceramic alternative. Verify that substitute parts maintain the same FIFO depth and DSP-compatible control logic.