AD7878KPZ-REEL

Overview

The AD7878KPZ-REEL is a complete 12-bit A/D converter featuring an integrated DSP interface with an 8-word FIFO memory. It operates on ±5 V supplies and accepts bipolar analog inputs within a ±3 V range. The device includes an on-chip track/hold amplifier, a 3 V Zener reference, and logic for FIFO management. Key performance metrics include a maximum data access time of 41 ns, a typical power dissipation of 60 mW, and a signal-to-noise ratio of 72 dB at a 10 kHz input frequency. It utilizes LC2MOS technology and interfaces directly with high-speed digital signal processors.

Feature Summary

• Integrated 8-word first-in, first-out (FIFO) memory reduces software overhead associated with servicing interrupts in DSP processors.
• On-chip status and control register allows programming of the effective FIFO length and provides monitoring of FIFO status.
• Fast 41 ns data access time enables direct interfacing to high-speed DSP processors and modern 16-bit microprocessors.
• LC2MOS fabrication process combines precision bipolar circuits with low-power CMOS logic for high dynamic performance.

Applications

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

Procurement Notes

Verify the specific grade suffix 'K' corresponds to the required temperature range and performance specifications against the manufacturer's ordering guide. Confirm that the 'REEL' designation indicates tape-and-reel packaging suitable for automated assembly processes. Ensure compatibility with existing PCB footprints for the PLCC package style before finalizing procurement orders.

Selection Notes

Select this component when a complete ADC solution with built-in FIFO buffering is required to minimize processor interrupt latency. The 41 ns access time makes it suitable for systems utilizing fast DSPs like the ADSP-2100 or TMS320 series. Consider the ±3 V input range and internal 3 V reference when designing the analog front-end circuitry to ensure optimal signal integrity without external components.

Part Context

The AD7878 is part of Analog Devices' LC2MOS family of complete A/D converters designed specifically for DSP applications. This series integrates track/hold amplifiers, references, and interface logic to simplify system design. The KPZ variant denotes a Plastic Leaded Chip Carrier package with industrial temperature grading, offering a compact form factor for space-constrained embedded designs.

Replacement Considerations

Direct substitutes include other AD7878 variants such as AD7878LP or AD7878LN, which share identical functionality but may differ in package type or speed grades. Verify pinout compatibility and electrical specifications when transitioning between different package styles or temperature ranges within the same product family.