AD7870LNZ

Overview

The AD7870LNZ is a complete monolithic 12-bit analog-to-digital converter featuring an internal track-and-hold amplifier, successive approximation ADC, and laser-trimmed clock. It operates from ±5 V supplies with a single-ended input range of ±3 V. The device provides parallel, byte, and serial digital interfaces with a data access time of 57 ns. Key performance metrics include a signal-to-noise ratio of 72 dB at a 10 kHz input frequency, a conversion time of 8 μs, and typical power dissipation of 60 mW. It is housed in a 24-pin PDIP package.

Feature Summary

• Integrated on-chip 3 V buried Zener reference with temperature compensation
• Versatile interface logic supporting parallel, byte, and serial data formats
• Laser-trimmed internal clock oscillator eliminating external timing components
• Fast microprocessor compatibility with 57 ns data access time

Applications

• Data acquisition systems requiring high-speed sampling
• Digital signal processing applications needing dynamic performance specifications
• Industrial control systems utilizing standard microprocessors or DSPs

Procurement Notes

Verify the specific suffix 'LNZ' against the manufacturer's current ordering guide to confirm the industrial temperature range (-40°C to +85°C) and lead-free packaging status. Ensure the pinout matches the 24-pin DIP configuration required for your PCB layout. Cross-reference the datasheet revision to confirm that all electrical parameters align with your system design requirements before finalizing procurement.

Selection Notes

Select the AD7870LNZ when a bipolar ±3 V input range is required alongside high dynamic accuracy. This variant offers superior SNR compared to other models in the series. Consider the available interface modes if interfacing with 8-bit or 16-bit processors. Verify that the ±5 V supply rails are compatible with your system power architecture before choosing this component over unipolar alternatives.

Part Context

The AD7870LNZ belongs to the AD7870/AD7875/AD7876 family of 12-bit sampling ADCs manufactured by Analog Devices. While sharing core architecture, the LNZ suffix specifically denotes the industrial temperature grade within the AD7870 model line. This distinguishes it from commercial variants and differentiates it from the unipolar AD7875 and wide-range AD7876 models.

Replacement Considerations

The AD7870KNZ serves as a direct functional substitute within the same package and specification family. Both parts share identical pinouts and electrical characteristics, differing primarily in their guaranteed operating temperature ranges. Verify thermal requirements before swapping between these specific suffixes.