Analog Devices Inc. AD7665ASTZRL

Overview

AD7665ASTZRL from Analog Devices is a 16-bit, 570 kSPS charge redistribution SAR analog-to-digital converter operating from a single 5 V supply. It delivers ±2.5 LSB INL, 90 dB SNR at 180 kHz, and supports bipolar (±10 V, ±5 V) and unipolar (0–10 V) input ranges. Its dual serial/parallel interface and hardware-calibrated performance make it suitable for high-accuracy data acquisition in spectrum analyzers and medical instrumentation.

For engineers reviewing the AD7665ASTZRL datasheet, AD7665ASTZRL pinout, AD7665ASTZRL application, or AD7665ASTZRL equivalent, key selection criteria include Warp/Normal/Impulse mode timing control, 48-lead LQFP package compatibility, 16-bit no-missing-codes assurance, and SPI/QSPI/MICROWIRE™-compatible serial operation with 3 V/5 V logic support.

Technical Context

The AD7665ASTZRL implements a charge redistribution SAR architecture with an internal switched-capacitor DAC and on-chip track-and-hold-eliminating pipeline delay and enabling true real-time conversion. Its resistor-based input scaler configures six analog input ranges by connecting IND(4R), INC(4R), INB(2R), and INA(R) to REF or INGND per Table I.

Three operational modes are controlled via WARP and IMPULSE pins: Warp Mode achieves 1.75 µs conversion time (570 kSPS), Normal Mode provides 2 µs cycle time (500 kSPS) with guaranteed accuracy across all throughput rates, and Impulse Mode scales power linearly with sampling rate down to 444 kSPS and 15 µW standby.

Key Specifications

Pinout & Package

AD7665ASTZRL is packaged in a 48-lead LQFP (Lead Count: 48; Body Size: 7 mm × 7 mm; Pitch: 0.5 mm). The exposed paddle must be connected to AGND for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with AD7664ASTZ, AD7665ASTZRL adds 70 kSPS throughput and tighter INL in identical footprint; versus AD7671ASTZ, it offers simpler single-ended interface at lower speed-making AD7665ASTZRL optimal for cost-constrained, mixed-signal embedded systems needing verified 16-bit linearity and flexible input configuration.

Availability

AD7665ASTZRL is available at Aetrix Electronics and suitable for high-speed data acquisition, spectrum analysis, medical instrumentation, process control, and automated test equipment requiring stable component supply and long-term manufacturing continuity.

Supply support for AD7665ASTZRL 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 AD7665ASTZRL belongs to the PulSAR® family of precision SAR ADCs designed for applications demanding high resolution, fast throughput, and low power-especially in portable instrumentation, communications infrastructure, and industrial automation.

FAQ

What is the maximum sampling rate of the AD7665ASTZRL and under what conditions is it achieved?

The AD7665ASTZRL achieves a maximum sampling rate of 570 kSPS in Warp Mode, which requires WARP pin HIGH and IMPULSE pin LOW. This mode mandates a minimum conversion rate to maintain full specified accuracy; timing is governed by a 1.75 µs complete cycle with 1 ms maximum inter-conversion interval. The AD7665ASTZRL must be operated within its specified AVDD/DVDD/OVDD voltage ranges and thermal limits to sustain this rate reliably.

Does the AD7665ASTZRL require an external reference voltage, and what are its requirements?

Yes, the AD7665ASTZRL requires an external reference voltage applied to the REF pin. The reference voltage must be between 2.3 V and 2.5 V, with typical operation at 2.5 V. It draws 114 µA at 570 kSPS throughput, so the reference source must be low-noise and capable of supplying this current without significant droop or ripple. The REFGND pin must be connected directly to the reference ground return path to minimize error contributions.

How does the AD7665ASTZRL handle input signal ranges, and can it accept both bipolar and unipolar inputs?

The AD7665ASTZRL supports both bipolar (e.g., ±10 V, ±5 V) and unipolar (e.g., 0–10 V, 0–5 V) input ranges through configurable connections of its four analog input terminals-IND(4R), INC(4R), INB(2R), and INA(R)-to REF or INGND as defined in Table I of the datasheet. This resistor-scaler network internally maps all ranges to a 0–2.5 V DAC input, eliminating need for external gain stages. The AD7665ASTZRL does not auto-detect range; configuration is static and set by PCB routing.

What digital interface options does the AD7665ASTZRL support, and how are they selected?

The AD7665ASTZRL supports both parallel (16-bit or 8-bit) and 2-wire serial interfaces (SPI/QSPI/MICROWIRE™/DSP-compatible). Interface mode is selected via the SER/PAR pin: LOW enables parallel operation on D[15:0], while HIGH reassigns pins for serial functions (SDOUT, SCLK, SYNC, etc.). The OB/2C pin selects straight binary or twos-complement output format, and the BYTESWAP pin controls MSB/LSB byte ordering in 8-bit parallel mode-all configurable without firmware changes.

Is the AD7665ASTZRL pin-compatible with earlier Analog Devices ADCs, and which ones?

Yes, the AD7665ASTZRL is pin-to-pin compatible with the AD7663ASTZ and AD7664ASTZ in the same 48-lead LQFP package. This allows direct drop-in replacement in existing designs, providing improved performance-including higher throughput (570 kSPS vs. 500 kSPS), better INL (±2.5 LSB vs. ±3 LSB), and enhanced power scalability in Impulse Mode-without PCB layout modifications. The AD7665ASTZRL maintains identical pin functions, timing, and power requirements for backward compatibility.