Analog Devices Inc. AD7875KR-REEL

Overview

AD7875KR-REEL from Analog Devices is a complete monolithic 12-bit sampling analog-to-digital converter (ADC) with integrated track-and-hold amplifier, laser-trimmed internal clock, and on-chip 3 V buried Zener reference. It supports unipolar 0 V to +5 V analog input range, achieves 72 dB SNR at 10 kHz, and delivers 57 ns data access time. Designed for high-fidelity data acquisition in DSP-based instrumentation and industrial control systems.

For engineers reviewing the AD7875KR-REEL datasheet, AD7875KR-REEL pinout, AD7875KR-REEL application, or AD7875KR-REEL equivalent, this page provides verified technical context, interface timing constraints, dynamic performance limits, unipolar input scaling details, and validated alternative options for signal chain design.

Technical Context

The AD7875KR-REEL implements a successive approximation register (SAR) architecture with a dedicated 2 μs track-and-hold amplifier and internal 3 V reference, enabling full-scale conversion of 0 V to +5 V signals without external components. Its internal clock is laser-trimmed to ±0.5% accuracy, guaranteeing 6.5–9 μs conversion time without external timing circuitry.

It supports three digital output formats-parallel 12-bit word, two 8-bit bytes, or serial data-with mode selection controlled by the 12/8/CLK pin. BUSY/INT and RD signals provide precise microprocessor handshake timing, and all logic interfaces meet TTL voltage thresholds with guaranteed 57 ns access time across temperature.

Key Specifications

Pinout & Package

AD7875KR-REEL is housed in a 24-pin, 0.3-inch-wide plastic dual-in-line package (PDIP), RoHS-compliant and tape-and-reel packaged per "-REEL" suffix. Pin layout matches industry-standard DIP footprint for drop-in replacement in legacy data acquisition designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit sampling ADC applications.

Compared with AD7875KR-REEL, AD7870KRZ supports bipolar inputs but cannot natively digitize 0–5 V signals, while ADS7822U reduces footprint and supply flexibility at the cost of interface versatility and guaranteed SNR performance.

Availability

AD7875KR-REEL is available at Aetrix Electronics and suitable for industrial data acquisition, test equipment, DSP-based signal processing, and medical instrumentation requiring stable component supply and long-term obsolescence management.

Supply support for AD7875KR-REEL includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD787x family was engineered for high-speed, high-accuracy data acquisition in embedded instrumentation and real-time control systems, emphasizing monolithic integration, dynamic performance, and microprocessor interoperability.

FAQ

What is the analog input voltage range supported by the AD7875KR-REEL?

The AD7875KR-REEL supports a unipolar 0 V to +5 V analog input range, optimized for direct connection to industrial sensors and single-supply signal conditioning circuits. This differs from the AD7870 (±3 V) and AD7876 (±10 V), and no external level-shifting is required when interfacing with 0–5 V sources. The input presents 25 kΩ impedance and uses straight-binary coding with 1.22 mV per LSB.

Does the AD7875KR-REEL require an external clock source?

No, the AD7875KR-REEL includes a laser-trimmed internal clock oscillator that guarantees conversion times of 6.5 μs minimum and 9 μs maximum. An external TTL-compatible clock may be applied to the CLK pin if tighter timing control or synchronization with system clocks is needed, but it is optional. Tying CLK to VSS enables the internal clock.

How does the AD7875KR-REEL handle digital interface modes?

The AD7875KR-REEL supports three output formats selected by the 12/8/CLK pin: +5 V enables 12-bit parallel only; 0 V enables byte or serial with gated SCLK; −5 V enables byte or serial with continuous SCLK. HBEN further configures DB11–DB0 for high/low byte selection in byte mode, and SSTRB/SCLK/SDATA pins support open-drain serial communication with external pull-ups.

What is the reference voltage specification for the AD7875KR-REEL?

The AD7875KR-REEL provides a 3.00 V ±10 mV buried Zener reference at the REF OUT pin, with ±35 ppm/°C temperature coefficient (L grade). It can source up to 500 μA and must be loaded with ≤50 pF capacitance. For 5 V or 10 V external references, Figure 7 in the datasheet shows resistor-divider scaling using the internal 3 V output.

Is the AD7875KR-REEL pin-compatible with other devices in the AD787x family?

Yes, the AD7875KR-REEL shares identical 24-pin PDIP pinout and signal definitions with AD7870KRZ and AD7876KRZ, including VIN, REF OUT, CONVST, RD, CS, BUSY/INT, and DB0–DB11. However, input range differences (0–5 V vs. ±3 V vs. ±10 V) and internal scaling networks mean direct substitution requires verification of analog front-end compatibility.