Analog Devices Inc. ADP1111ARZ-5-REEL

Overview

ADP1111ARZ-5-REEL from Analog Devices is a micropower step-up/step-down switching regulator IC with fixed 5 V output, internal 1 A power switch, 72 kHz oscillator, and operation from 2 V to 30 V input. It supports boost (e.g., 3 V → 5 V), buck (e.g., 12 V → 5 V), and inverting topologies using only three external components, and delivers up to 200 mA at 5 V from a 12 V input in step-down mode.

For engineers reviewing the ADP1111ARZ-5-REEL datasheet, ADP1111ARZ-5-REEL pinout, ADP1111ARZ-5-REEL application, or ADP1111ARZ-5-REEL equivalent, key selection considerations include its dual-mode topology flexibility, user-adjustable current limit via ILIM resistor, low 300 μA quiescent current in shutdown, integrated 1.25 V reference, and SO-8 package compatibility with surface-mount inductor designs for portable power systems.

Technical Context

The ADP1111ARZ-5-REEL implements a gated-oscillator control architecture with a 72 kHz fixed-frequency PWM generator and comparator-based feedback loop referencing an internal 1.25 V bandgap. Its dual-access power switch (SW1 collector, SW2 emitter) enables reconfigurable step-up, step-down, or inverting operation without external transistors.

It integrates a programmable current-limit circuit (via ILIM-to-VIN resistor), open-collector gain block (AO pin) usable for low-battery detection or undervoltage lockout, and hysteresis-stabilized regulation-eliminating need for external frequency compensation. Output voltage is fixed at 5.00 V ±2.5% (4.75–5.25 V) with 32–50 mV hysteresis, verified across 0°C to +70°C.

Key Specifications

Pinout & Package

ADP1111ARZ-5-REEL is housed in an 8-lead SOIC (SO-8) package with standard 1.27 mm pitch, RoHS-compliant matte tin lead finish, and thermal pad not present. Pin 1 is ILIM, pin 4 is GND, pin 5 is VIN, pin 6 is SW2, pin 7 is AO, and pin 8 is FB/SENSE. The device uses exposed copper leads for solderability and thermal dissipation under JEDEC MS-012 standards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar switching regulator applications.

Compared with TPS61040DRVR and MAX630ESA+, the ADP1111ARZ-5-REEL uniquely combines step-up/step-down topology flexibility, programmable current limit, and system-monitoring AO output in a single SO-8 package-making it optimal for multi-function portable power where design reuse and feature integration reduce total solution size and cost.

Availability

ADP1111ARZ-5-REEL is available at Aetrix Electronics and suitable for portable medical sensors, laptop peripheral cards, flash memory VPP generators, and remote control power supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ADP1111ARZ-5-REEL 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 instrumentation, industrial automation, communications, and healthcare markets.

The ADP1111 product line was designed for micropower, multi-topology DC-DC conversion in battery-operated and space-constrained systems-emphasizing low IQ, minimal external components, and reconfigurable switch architecture.

FAQ

What is the maximum output current capability of the ADP1111ARZ-5-REEL in step-down mode?

The ADP1111ARZ-5-REEL delivers up to 200 mA at 5 V from a 12 V input in step-down mode, as specified in the datasheet's General Description. This assumes proper thermal management on a standard FR-4 PCB with 2 oz copper and adequate copper pour. At higher ambient temperatures or with reduced copper area, output current must be derated per the device's thermal resistance (θ_JA ≈ 150°C/W) and maximum junction temperature of 125°C. The internal 1 A switch supports this rating, but sustained 200 mA requires attention to inductor saturation current and diode forward drop.

Can the ADP1111ARZ-5-REEL operate from a 1.8 V input source?

No, the ADP1111ARZ-5-REEL cannot operate from a 1.8 V input. Its minimum input voltage is 2.0 V in step-up mode, as confirmed in the Absolute Maximum Ratings and Specifications tables. Below 2.0 V, the internal reference and oscillator fail to start reliably. For sub-2 V battery applications, Analog Devices recommends the ADP1110, which is explicitly designed for inputs down to 0.9 V and shares functional compatibility with the ADP1111 family while using a different control scheme optimized for ultra-low voltage.

How is the 5 V output accuracy maintained across temperature and load for the ADP1111ARZ-5-REEL?

The ADP1111ARZ-5-REEL maintains 5 V output accuracy through laser-trimmed internal resistive feedback dividers and a tightly controlled 1.25 V ±4% bandgap reference. Over 0°C to +70°C and full load range, output remains within 4.75–5.25 V (±2.5%), as validated in the "OUTPUT SENSE VOLTAGE" specification table for ADP1111-5. Hysteresis of 32–50 mV ensures loop stability without external compensation, and line regulation is specified at 0.02–0.4 %/V depending on input range-minimizing drift during battery discharge.

Does the ADP1111ARZ-5-REEL require external compensation components for stability?

No, the ADP1111ARZ-5-REEL does not require external compensation components. Its comparator-based feedback loop incorporates built-in hysteresis (8–12.5 mV), which provides inherent loop stability across all operating conditions and eliminates the need for external RC networks or type-II/III compensators. This is explicitly stated in the Theory of Operation section: "The comparator includes a small amount of hysteresis, which ensures loop stability without requiring external components for frequency compensation." Stability is guaranteed with standard ceramic or tantalum output capacitors.

What is the purpose of the AO pin on the ADP1111ARZ-5-REEL, and how is it typically used?

The AO (Auxiliary Gain) pin on the ADP1111ARZ-5-REEL is an open-collector NPN output capable of sinking 300 μA, driven by an uncommitted gain block with 1000–6000 V/V gain. It is commonly used to implement low-battery detection by connecting a resistor divider from VIN to GND with the junction at the SET pin; when VIN drops below the trip point (set relative to the internal 1.25 V reference), AO pulls low. Other valid uses include undervoltage lockout, post-linear regulation, or error amplification-enabling system-level monitoring without adding discrete comparators or op-amps.