Analog Devices Inc. AD4022BRMZ

Overview

AD4022BRMZ from Analog Devices is a 20-bit, 500 kSPS differential successive approximation register (SAR) analog-to-digital converter with Easy Drive architecture, ±VREF input range (2.4 V to 5.1 V reference), −40°C to +125°C operation, and 3 mm × 4.90 mm MSOP-10 package. It delivers ±3.1 ppm INL, 100.5 dB SNR at 1 kHz, and 131 dB oversampled dynamic range at OSR = 1024 for precision data acquisition in battery-powered instrumentation.

For engineers reviewing the AD4022BRMZ datasheet, AD4022BRMZ pinout, AD4022BRMZ application, or AD4022BRMZ equivalent, key selection considerations include its 500 kSPS throughput with 1770 ns acquisition phase, high-Z mode reducing input current to 1 µA, input overvoltage clamp sinking 50 mA, SPI/QSPI/MICROWIRE-compatible interface with 1.71–5.5 V VIO support, and guaranteed 20-bit no-missing-codes performance across industrial temperature range.

Technical Context

The AD4022BRMZ implements a differential SAR architecture with integrated input span compression and high-impedance acquisition mode, enabling single-supply operation without negative rail while preserving full 20-bit code range. Its Easy Drive design reduces input kickback and extends acquisition time to ≥77% of conversion cycle at 500 kSPS.

It features a dedicated input overvoltage clamp protecting IN+/IN− up to 5.4 V (at VREF = 5 V) with 360 ns deactivation, and supports flexible serial interface modes including CS-based 3-/4-wire and daisy-chain configurations with status bit reporting - all synchronized to a single SCK clock with programmable timing via CNV/SDI edge detection.

Key Specifications

Pinout & Package

AD4022BRMZ is housed in a 10-lead MSOP package (3 mm × 4.90 mm) with exposed pad connected to GND. Pin 1 is REF; pin 5 is GND; pin 6 is CNV; pins 7–9 are SDO/SCK/SDI; pin 10 is VIO. The exposed pad is not required for specified performance but improves thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-accuracy SAR ADC applications.

Compared with AD4022BRMZ, AD4021BRMZ trades lower power for higher speed, while AD4003BRMZ sacrifices 2 bits and oversampling capability for reduced cost and footprint compatibility - making AD4022BRMZ optimal for power-constrained, high-fidelity 20-bit acquisition at 500 kSPS.

Availability

AD4022BRMZ is available at Aetrix Electronics and suitable for automated test equipment, medical data acquisition systems, and battery-powered instrumentation requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for AD4022BRMZ 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 AD402x family was designed specifically for precision, low-power, high-channel-density data acquisition systems requiring 20-bit accuracy, Easy Drive simplification, and robust operation from −40°C to +125°C.

FAQ

What is the maximum achievable throughput for AD4022BRMZ and what conditions are required?

The AD4022BRMZ achieves a maximum throughput of 500 kSPS. This rate is guaranteed with turbo mode enabled and an SCK clock frequency of at least 71 MHz. At lower SCK rates, throughput decreases per Table 4 in the datasheet. The 500 kSPS specification applies across the full −40°C to +125°C temperature range and is supported by the 1770 ns acquisition phase and 2000 ns minimum conversion cycle time.

Does AD4022BRMZ require an external ADC driver amplifier?

No, AD4022BRMZ does not require an external ADC driver amplifier due to its Easy Drive architecture. With input current reduced to 1 µA at 500 kSPS and an acquisition phase of 1770 ns (≥77% of cycle time), the device can be directly driven by low-output-impedance sources such as precision op-amps or resistive sensor bridges without signal degradation or settling errors.

What reference voltage range is supported by AD4022BRMZ and how does it affect performance?

AD4022BRMZ supports an external reference voltage (VREF) from 2.4 V to 5.1 V. Performance metrics including SNR (100.5 dB at 5 V), THD (−123 dB), and oversampled dynamic range (131 dB at OSR = 1024) are specified at VREF = 5 V. At VREF = 2.5 V, SNR drops to 94.7 dB, confirming that higher reference voltages improve noise floor and dynamic range - critical for maximizing effective resolution.

How does the input overvoltage clamp function in AD4022BRMZ and what protection does it provide?

The AD4022BRMZ input overvoltage clamp activates when IN+ or IN− exceeds VREF by ~0.25 V (e.g., 5.25 V threshold at VREF = 5 V), sinking up to 50 mA while limiting REF pin disturbance. Deactivation occurs within 360 ns after overvoltage removal. This feature eliminates the need for external clamping diodes and protects both the ADC inputs and reference circuitry during transient events in industrial or medical environments.

Is AD4022BRMZ compatible with 1.8 V digital interfaces and what logic levels does it support?

Yes, AD4022BRMZ supports 1.8 V digital interfaces via its separate VIO supply pin (Pin 10), which accepts 1.71 V to 5.5 V. Input logic thresholds scale with VIO: for VIO ≤ 2.7 V, VIH is 0.8 × VIO and VIL is 0.2 × VIO. At VIO = 1.8 V, this yields VIH = 1.44 V and VIL = 0.36 V - ensuring reliable communication with 1.8 V FPGAs, microcontrollers, and isolated digital isolators without level-shifting.