AD7875KPZ

Overview

The AD7875KPZ is a complete monolithic 12-bit successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from ±5 V power supplies and features an internal 3 V buried Zener reference, a track-and-hold amplifier, and a laser-trimmed clock oscillator. The device accepts a unipolar analog input range of 0 V to +5 V. It provides versatile digital interface options including parallel, byte, and serial data formats. Key electrical specifications include a maximum conversion time of 9 μs using the internal clock, a typical power dissipation of 60 mW, and a signal-to-noise ratio of 70 dB at a 10 kHz input frequency with a 100 kHz sampling rate.

Feature Summary

• Integrates a 12-bit SAR ADC with a 2 μs track-and-hold amplifier and on-chip reference.
• Supports multiple data output formats: single 12-bit parallel word, two 8-bit bytes, or serial transmission.
• Features a self-contained laser-trimmed internal clock that eliminates external timing components.
• Provides fast microprocessor interfacing with a 57 ns data access time.

Applications

• Data acquisition systems requiring 12-bit resolution.
• Digital signal processing (DSP) applications utilizing dynamic performance specifications.
• Industrial control systems interfacing with modern 8-bit and 16-bit microprocessors.

Procurement Notes

Verify the specific suffix K for commercial temperature range (0°C to +70°C) and PZ for lead-free plastic DIP packaging against the official Analog Devices ordering guide. Confirm pin compatibility and voltage supply requirements match the target circuit design before integration.

Selection Notes

Select the AD7875KPZ when a unipolar 0 V to +5 V input range is required. Compare against AD7870 for bipolar ±3 V inputs or AD7876 for bipolar ±10 V inputs. Ensure the system can accommodate the ±5 V dual supply requirement and the specific package constraints of the 24-pin DIP form factor.

Part Context

This component belongs to the AD7870/AD7875/AD7876 family of 12-bit, 100 kHz sampling ADCs. While sharing identical architecture and interface logic, the AD7875 variant is distinguished by its unipolar input specification. The KPZ suffix denotes the commercial temperature grade and plastic dual-in-line package configuration within this product line.

Replacement Considerations

Publicly confirmed substitutes are not identified in the provided documentation. Cross-referencing with the manufacturer's current product portfolio is recommended to identify any updated revisions or alternative packages offering equivalent electrical characteristics.

FAQ

How is the internal clock enabled?

The internal laser-trimmed clock is enabled by tying the CLK pin (Pin 3) to VSS (Negative Supply).

What is the function of the 12/8/CLK pin?

This pin selects the data output format. A high level (+5 V) enables 12-bit parallel mode, while low (0 V) or negative (-5 V) levels enable byte or serial modes.

Can the internal reference be used externally?

Yes, the REF OUT pin provides the internal 3 V reference, capable of sourcing up to 500 μA to an external load.