Analog Devices Inc. AD7091RBCPZ-RL

Overview

AD7091RBCPZ-RL from Analog Devices is a 12-bit successive approximation ADC with ultralow power consumption (349 µA typical at 3 V, 1 MSPS), 2.5 V internal reference (±4.5 ppm/°C drift), and SPI-compatible serial interface. It operates from a single 2.7 V to 5.25 V supply with independent VDRIVE (1.65 V to 5.25 V) for logic-level flexibility, and targets battery-powered data acquisition in handheld meters and medical instruments.

For engineers reviewing the AD7091RBCPZ-RL datasheet, AD7091RBCPZ-RL pinout, AD7091RBCPZ-RL application, or AD7091RBCPZ-RL equivalent, key selection criteria include its 1 MSPS throughput with sub-1 mW active power, −40°C to +125°C operation, 10-lead 3 mm × 2 mm LFCSP package, and integrated track-and-hold supporting >7 MHz input bandwidth.

Technical Context

The AD7091RBCPZ-RL implements a charge redistribution SAR architecture with on-chip oscillator and conversion control logic driven by CONVST edge triggering. Its track-and-hold amplifier achieves 350 ns acquisition time for full-scale steps and supports analog inputs from 0 V to VREF (internal 2.5 V or external 2.7 V–5.25 V).

It features dual-supply independence: VDD powers analog circuitry and internal reference, while VDRIVE sets digital I/O voltage levels-enabling direct interfacing with 1.8 V or 3.3 V processors without level shifters. Power-down mode reduces current to 264 nA at 3 V, and BUSY indicator support simplifies timing-critical host synchronization.

Key Specifications

Pinout & Package

AD7091RBCPZ-RL is packaged in a 10-lead, 3 mm × 2 mm LFCSP (Lead Frame Chip Scale Package) with exposed pad (EPAD) for thermal and mechanical reliability. The EPAD must be soldered to GND for optimal thermal performance and solder joint integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7042IRUGR, AD7091RBCPZ-RL provides integrated reference and VDRIVE flexibility at slightly higher active current; compared with MAX11100ETE+, it delivers 2× lower power and superior thermal performance in the same industrial temperature range.

Availability

AD7091RBCPZ-RL is available at Aetrix Electronics and suitable for battery-powered systems, handheld meters, and medical instruments requiring stable component supply across long production lifecycles and demanding environmental conditions.

Supply support for AD7091RBCPZ-RL 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 industrial, automotive, communications, and healthcare markets since 1965.

The AD7091R family was designed specifically for ultralow-power, high-precision data acquisition in space-constrained, battery-operated applications-emphasizing integration, thermal robustness, and ease of system-level design.

FAQ

What is the operating temperature range of the AD7091RBCPZ-RL?

The AD7091RBCPZ-RL is specified for continuous operation from −40°C to +125°C. This extended industrial temperature range is validated across all electrical parameters-including INL, SNR, and power consumption-and supports deployment in harsh environments such as automotive under-hood modules, industrial motor drives, and sterilizable medical devices. The LFCSP package's low thermal resistance (θJA = 33.2°C/W) ensures reliable junction temperature control even at maximum ambient.

Does the AD7091RBCPZ-RL require an external reference?

No, the AD7091RBCPZ-RL includes a fully specified on-chip 2.5 V reference with ±4.5 ppm/°C typical drift and 2.5 V ±10 mV accuracy. When using the internal reference, the REFIN/REFOUT pin must be decoupled with a 2.2 µF capacitor. An external reference (2.7 V to VDD) may be applied to the same pin to override the internal source-providing design flexibility without additional pins or routing complexity.

How does the VDRIVE pin function in the AD7091RBCPZ-RL?

The VDRIVE pin on the AD7091RBCPZ-RL sets the logic voltage level for all digital I/Os (CS, SCLK, SDO, CONVST), independent of the analog supply VDD. It accepts 1.65 V to 5.25 V and defines VIH (0.7 × VDRIVE) and VOL (0.4 V). This allows direct interfacing with 1.8 V or 3.3 V microcontrollers without level-shifting components-reducing BOM count, PCB area, and signal integrity risk in mixed-voltage systems.

What is the minimum acquisition time required before conversion in the AD7091RBCPZ-RL?

The AD7091RBCPZ-RL track-and-hold amplifier requires 350 ns to settle to ±0.5 LSB after a full-scale step input, as confirmed in the datasheet's timing specifications. This acquisition time is fixed and internally managed-no external timing control is needed. For optimal performance, ensure the analog source impedance remains ≤1 kΩ to avoid degradation of THD and SNR, especially at high input frequencies.

Can the AD7091RBCPZ-RL operate with a free-running SCLK?

No-using a free-running SCLK degrades dynamic performance (SNR, SINAD) due to noise coupling into the analog section during acquisition. The AD7091RBCPZ-RL datasheet explicitly requires burst-mode SCLK operation: SCLK must be inactive (high or low) until CS is asserted and conversion completes. Burst mode ensures clean acquisition windows and maintains 69 dB SNR performance at 1 MSPS throughput.