Analog Devices Inc. AD7865YSZ-1

Overview

AD7865YSZ-1 from Analog Devices is a four-channel, simultaneous-sampling, 14-bit analog-to-digital converter (ADC) with 2.4 µs conversion time per channel, ±10 V/±5 V input ranges, and integrated track/hold amplifiers. It operates from a single 5 V supply, consumes 115 mW typical power, and delivers 77 dB SNR at full temperature range - used in AC motor control and industrial power monitoring systems requiring phase-coherent multichannel acquisition.

For engineers reviewing the AD7865YSZ-1 datasheet, AD7865YSZ-1 pinout, AD7865YSZ-1 application, or AD7865YSZ-1 equivalent, key selection criteria include simultaneous sampling capability, aperture delay matching ≤4 ns, bipolar input support, 14-bit resolution with ±2 LSB INL, and PQFP-44 package compatibility for high-density industrial PCB layouts.

Technical Context

The AD7865YSZ-1 implements a successive approximation ADC architecture with four independent track/hold amplifiers, enabling true simultaneous sampling across all four analog inputs to preserve inter-channel phase relationships. Its internal 2.5 V reference, laser-trimmed clock oscillator, and hardware/software channel selection logic allow flexible sequencing without external timing components.

It supports dual operation modes: reading data after full conversion sequence (BUSY-driven) or interleaved reads per channel (EOC-driven), with timing validated for 350 kSPS single-channel and 100 kSPS four-channel throughput. Input overvoltage protection sustains ±18 V on ±10 V range channels without damage or cross-channel corruption.

Key Specifications

Pinout & Package

The AD7865YSZ-1 is housed in a 44-lead Plastic Quad Flatpack (PQFP) measuring 10 mm × 10 mm with 0.8 mm lead pitch. All AGND pins (12, 17, 23, 26) must be connected to system analog ground plane; DVDD and AVDD are externally tied together with local 0.1 µF decoupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel simultaneous-sampling ADC applications.

Compared with AD7865YSZ-1, AD7656ASTZ offers two extra channels and 2-bit higher resolution but sacrifices parallel interface and 3 V processor compatibility; ADS8588HIPM adds two more channels and lower power but requires external timing and reference components, increasing BOM count and layout complexity.

Availability

AD7865YSZ-1 is available at Aetrix Electronics and suitable for AC motor control, industrial power monitoring, and uninterruptible power supply applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD7865YSZ-1 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 is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD7865 product line delivers simultaneous-sampling ADCs optimized for industrial automation, motor control, and power quality instrumentation - designed to replace discrete track/hold + ADC solutions with integrated, phase-coherent multichannel acquisition.

FAQ

What input voltage ranges does the AD7865YSZ-1 support?

The AD7865YSZ-1 supports ±10 V and ±5 V bipolar input ranges exclusively. It does not support unipolar 0 V to 2.5 V or 0 V to 5 V ranges (those are handled by AD7865-2 variants) or ±2.5 V (handled by AD7865-3). This makes AD7865YSZ-1 ideal for legacy industrial sensor interfaces requiring standard bipolar scaling. The part maintains ±2 LSB INL and 77 dB SNR across its full –40°C to +105°C operating range.

How does the AD7865YSZ-1 achieve simultaneous sampling across four channels?

The AD7865YSZ-1 achieves true simultaneous sampling using four independent, matched track/hold amplifiers - one per analog input pair (VIN1A/VIN1B through VIN4A/VIN4B). A single CONVST rising edge freezes all four amplifiers at the exact same instant, preserving inter-channel phase relationships. Aperture delay matching is guaranteed ≤4 ns, ensuring <0.02° phase error at 100 kHz - critical for vector-controlled motor drives and power quality analyzers relying on coherent multichannel capture.

Can the AD7865YSZ-1 interface directly with 3 V microcontrollers?

Yes, the AD7865YSZ-1 supports direct 3 V logic interfacing via its dedicated VDRIVE pin (Pin 36), which powers the DB0–DB13 data bus, BUSY, EOC, and FRSTDATA outputs independently. When VDRIVE is supplied with 3 V ±10%, the outputs meet 3 V TTL logic thresholds while maintaining full timing compliance. This eliminates level-shifting circuitry in systems using modern low-voltage MCUs or DSPs - a key advantage over legacy ADCs lacking separate I/O supply rails.

What is the purpose of the FRSTDATA pin on the AD7865YSZ-1?

The FRSTDATA pin (Pin 2) is a logic output that goes high to indicate the first valid data word is available in the output data register - specifically signaling that the Output Data Register Pointer has advanced to Register 1. This provides precise synchronization for firmware-driven data capture, especially in EOC-driven interleaved read mode. Unlike BUSY (which marks end-of-sequence) or EOC (which pulses per channel), FRSTDATA identifies the earliest point at which the first converted result can be safely latched, optimizing read timing in high-throughput applications.

Does the AD7865YSZ-1 include an internal voltage reference?

Yes, the AD7865YSZ-1 integrates a 2.5 V ±20 mV internal reference accessible at the VREF pin (Pin 24), eliminating the need for an external reference in most applications. The reference features 25 ppm/°C temperature coefficient and 6 kΩ output impedance. For higher precision, the internal reference can be overdriven by an external 2.5 V ±5% source - allowing calibration-grade accuracy while retaining the convenience of internal reference architecture. This dual-mode reference design balances cost, board space, and performance flexibility.