Analog Devices Inc. AD7989-5BRMZ-RL7

Overview

AD7989-5BRMZ-RL7 from Analog Devices is an 18-bit, 500 kSPS successive approximation register (SAR) analog-to-digital converter with true differential input, ±V_REF range, zero-latency architecture, and SPI-/QSPI-/MICROWIRE-compatible serial interface. It operates from a single 2.5 V supply with independent 1.71 V to 5.5 V digital I/O (VIO), supports external reference voltages from 2.4 V to 5.1 V, and delivers 97 dB SINAD at 1 kHz with 5 V reference - ideal for high-precision data acquisition in medical instrumentation and automated test equipment.

For engineers reviewing the AD7989-5BRMZ-RL7 datasheet, AD7989-5BRMZ-RL7 pinout, AD7989-5BRMZ-RL7 application, or AD7989-5BRMZ-RL7 equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative parts with documented differences, and supply-chain support tailored for industrial embedded and precision measurement systems.

Technical Context

The AD7989-5BRMZ-RL7 implements a charge-redistribution SAR architecture with on-chip track-and-hold, enabling zero pipeline latency and immediate availability of conversion results. Its differential input stage accepts ±V_REF signals with 67 dB common-mode rejection at 450 kHz and supports true bipolar operation when paired with an external reference.

It features dual-mode serial interface: CS mode (3- or 4-wire) and chain mode for daisy-chaining multiple ADCs on one SDO line. The CNV rising edge initiates sampling and selects interface mode, while SCK timing varies with VIO voltage level (e.g., min 10.5 ns period for VIO > 4.5 V), ensuring compatibility across 1.8 V–5 V logic families.

Key Specifications

Pinout & Package

AD7989-5BRMZ-RL7 is packaged in a 10-lead LFCSP (3 mm × 3 mm, CP-10-9), with exposed pad (EPAD) recommended to be connected to GND for thermal performance but not required for electrical functionality.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 18-bit SAR ADC applications.

Compared with AD7989-1BRMZ-RL7 and AD4011BCPZ-RL7, the AD7989-5BRMZ-RL7 uniquely balances 500 kSPS speed, 3.5 mW power, and drop-in LFCSP compatibility - making it optimal for space-constrained, medium-speed precision DAQ where minimal BOM change and proven thermal performance are priorities.

Availability

AD7989-5BRMZ-RL7 is available at Aetrix Electronics and suitable for medical instrumentation, automated test equipment, and industrial data acquisition systems requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for AD7989-5BRMZ-RL7 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 global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision measurement, industrial, and communications markets since 1965.

The AD7989 family targets high-accuracy, low-power, medium-speed data acquisition - designed specifically for applications demanding 18-bit resolution, zero latency, and robust serial interfacing in thermally and electrically noisy environments.

FAQ

What is the maximum sample rate supported by the AD7989-5BRMZ-RL7?

The AD7989-5BRMZ-RL7 supports a maximum throughput of 500 kSPS, with a minimum conversion cycle time of 2 µs. This is confirmed in Table 4 of the Rev. C datasheet under "THROUGHPUT RATE" and validated by timing parameters including tCONV = 1600 ns and tCYC = 2 µs for the AD7989-5 variant. The AD7989-5BRMZ-RL7 does not support higher rates such as 1 MSPS - that capability belongs to the AD4011BCPZ-RL7.

Does the AD7989-5BRMZ-RL7 require an external reference voltage?

Yes, the AD7989-5BRMZ-RL7 requires an external reference voltage applied to the REF pin, with a specified range of 2.4 V to 5.1 V. The device has no internal reference; its full-scale differential input range is ±V_REF, and accuracy metrics (INL, gain error) assume a stable, low-noise external reference. The REF pin draws up to 250 µA load current at 5 V, per Table 3.

Can the AD7989-5BRMZ-RL7 operate with a 1.8 V digital interface?

Yes, the AD7989-5BRMZ-RL7 supports 1.8 V digital logic through its dedicated VIO supply pin (Pin 10), which accepts 1.71 V to 5.5 V. When VIO = 1.8 V, digital input thresholds adjust accordingly (e.g., VIH ≥ 0.9 × VIO = 1.62 V), and SCK timing relaxes to accommodate slower edges (min 22 ns period). This is explicitly defined in Tables 2 and 4 of the datasheet.

What package type is used for the AD7989-5BRMZ-RL7?

The AD7989-5BRMZ-RL7 uses a 10-lead LFCSP package (3 mm × 3 mm, CP-10-9), as indicated by the "BRMZ" suffix and confirmed in the Ordering Guide (Page 23) and Figure 4 of the Rev. C datasheet. Its thermal resistance is θJA = 48.7°C/W and θJC = 2.96°C/W, significantly lower than the MSOP variant (RM-10), making it suitable for compact, thermally demanding layouts.

Is the AD7989-5BRMZ-RL7 pin-compatible with the AD7989-1BRMZ-RL7?

Yes, the AD7989-5BRMZ-RL7 and AD7989-1BRMZ-RL7 share identical pin configurations, package footprints (10-lead LFCSP), and interface protocols - they differ only in maximum throughput (500 kSPS vs. 100 kSPS) and corresponding power consumption. This allows direct substitution in existing designs where speed upgrade is needed, provided the host firmware supports the faster timing requirements.