Analog Devices Inc. AD7875KPZ

Overview

AD7875KPZ 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 100 kHz sampling rate, delivers 72 dB SNR at 10 kHz input, and features 57 ns data access time. It is used in precision data acquisition systems requiring high dynamic performance and microprocessor compatibility.

For engineers reviewing the AD7875KPZ datasheet, AD7875KPZ pinout, AD7875KPZ application, or AD7875KPZ equivalent, this page provides verified technical context, real-world interface timing constraints, confirmed unipolar input behavior, validated package mapping to 28-pin PLCC, and selection-critical differences among functionally aligned alternatives.

Technical Context

The AD7875KPZ 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 scaling components. Its laser-trimmed on-chip clock guarantees 6.5–9 μs conversion time and eliminates need for 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 timing control for microprocessor interfacing, and all logic inputs meet TTL voltage thresholds with ±10 μA input current.

Key Specifications

Pinout & Package

AD7875KPZ is housed in a 28-pin plastic leaded chip carrier (PLCC) package with JEDEC MO-118AC outline, 0.4 inch body width, and gull-wing leads. Pin 1 is identified by a corner notch; thermal pad is not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7875KPZ, AD7870KPZ and AD7876KPZ share identical conversion architecture, timing, and packaging-but differ fundamentally in input range, coding format, and reference utilization; none are pin-compatible replacements without signal conditioning changes.

Availability

AD7875KPZ is available at Aetrix Electronics and suitable for industrial process monitoring, test & measurement equipment, and medical instrumentation requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for AD7875KPZ 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 semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD7875KPZ belongs to the LC2MOS Complete 12-Bit Sampling ADC family, designed specifically for embedded data acquisition systems demanding self-contained accuracy, microprocessor compatibility, and minimal external component count.

FAQ

What is the analog input voltage range supported by the AD7875KPZ?

The AD7875KPZ supports a unipolar 0 V to +5 V analog input range. Its input structure is optimized for this range, delivering straight binary output coding with 1.22 mV per LSB. Unlike the AD7870KPZ (±3 V) or AD7876KPZ (±10 V), the AD7875KPZ does not accept negative input voltages or bipolar ranges without external level-shifting circuitry.

Does the AD7875KPZ require an external clock source?

No, the AD7875KPZ does not require an external clock source. It integrates a laser-trimmed internal 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 precise synchronization or variable sampling rates are needed, but it is optional-not mandatory-for basic operation.

How is the AD7875KPZ interfaced to an 8-bit microprocessor bus?

The AD7875KPZ supports byte-mode interfacing using the HBEN (High Byte Enable) and 12/8/CLK pins. When 12/8/CLK is set to 0 V and HBEN is toggled, DB7–DB0 deliver lower or upper 8-bit bytes sequentially. This allows direct connection to 8-bit data buses without multiplexing logic, and is explicitly validated in the AD7875KPZ timing specifications for t3, t6, and t15–t18 parameters.

What is the role of the REF OUT pin on the AD7875KPZ?

The REF OUT pin on the AD7875KPZ provides the internal 3.00 V ±10 mV buried Zener reference voltage, used internally for DAC and comparator biasing. It can supply up to 500 μA to external circuitry, such as op-amp bias networks or sensor excitation, but must not be loaded beyond 50 pF capacitance to maintain stability. Its tempco is ±35 ppm/°C for L/C grade devices.

Can the AD7875KPZ operate from a single +5 V supply?

No, the AD7875KPZ cannot operate from a single +5 V supply. It requires dual ±5 V supplies (VDD = +5 V ±5%, VSS = −5 V ±5%) to power its internal track-and-hold amplifier, reference, and analog core. Attempting single-supply operation violates Absolute Maximum Ratings and will result in nonfunctional or damaged units, as confirmed in Table 4 of the AD7875KPZ datasheet.