Analog Devices Inc. ADP1111AN-3.3

Overview

ADP1111AN-3.3 from Analog Devices is a micropower step-up/step-down switching regulator with fixed 3.3 V output, internal 1 A power switch, 72 kHz oscillator, and operation from 2 V to 30 V input. It delivers up to 100 mA at 5 V (step-up from 3 V) or 200 mA at 5 V (step-down from 12 V), used in battery-powered portable instruments and flash memory VPP generators.

For engineers reviewing the ADP1111AN-3.3 datasheet, ADP1111AN-3.3 pinout, ADP1111AN-3.3 application, or ADP1111AN-3.3 equivalent, key selection factors include its dual-mode topology support, user-adjustable current limit via ILIM resistor, low 300 μA quiescent current in shutdown, and compatibility with surface-mount inductors for compact DC/DC designs.

Technical Context

The ADP1111AN-3.3 implements a gated-oscillator control architecture with a 1.25 V internal reference and comparator-based regulation loop. Its dual-collector/emitter switch configuration enables configurable step-up, step-down, or inverting topologies using only three external components.

It integrates an open-collector gain block (AO pin) for low-battery detection or undervoltage lockout, and supports programmable current limiting via a resistor from ILIM to VIN-enabling precise peak switch current control across input voltage ranges.

Key Specifications

Pinout & Package

ADP1111AN-3.3 is housed in an 8-lead plastic DIP (N-8) package with 0.3-inch body width and standard 0.1-inch lead pitch. Pin 1 is marked with a notch or dot; pin numbering follows counterclockwise convention from top-left.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADP1111AN-3.3, the ADP1111AR-3.3 offers identical electrical performance in a smaller footprint for production, while the MAX630ESA+ trades topology versatility for higher output current and frequency-making it less suitable for battery-fed step-up or dual-mode designs.

Availability

ADP1111AN-3.3 is available at Aetrix Electronics and suitable for portable instrument power, flash memory VPP generation, laptop peripheral card supply, and battery backup voltage translation requiring stable component supply across long-lifecycle embedded programs.

Supply support for ADP1111AN-3.3 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, headquartered in Norwood, MA, with R&D and manufacturing facilities worldwide.

The ADP1111 family was designed specifically for ultra-low-power, multi-topology DC/DC conversion in space-constrained portable electronics-emphasizing micropower operation, minimal external components, and flexible voltage translation.

FAQ

What is the maximum output current capability of the ADP1111AN-3.3 in step-up mode?

The ADP1111AN-3.3 delivers up to 100 mA at 5 V when stepping up from a 3 V input, as specified in the datasheet's General Description. This assumes optimal component selection (e.g., low-ESR capacitor, Schottky diode) and ambient temperature ≤+70°C. Output current is limited by internal switch saturation voltage and thermal dissipation-not by the 3.3 V output rating itself.

Can the ADP1111AN-3.3 operate in inverting (positive-to-negative) mode?

Yes, the ADP1111AN-3.3 supports inverting mode using its accessible SW1 and SW2 pins, as confirmed in the Functional Block Diagrams and Theory of Operation sections. The device requires no additional external control logic-only proper inductor and diode placement per Figure 22 in the datasheet.

Does the ADP1111AN-3.3 require external feedback resistors for 3.3 V regulation?

No. The ADP1111AN-3.3 integrates laser-trimmed feedback resistors internally, so the FB (SENSE) pin connects directly to the output. This eliminates external resistor matching errors and reduces sensitivity to PCB leakage currents-critical for stable 3.3 V regulation in low-power systems.

What is the purpose of the AO pin on the ADP1111AN-3.3?

The AO pin is the open-collector output of an uncommitted gain block with internal 1.25 V reference. On the ADP1111AN-3.3, it can be configured as a low-battery detector by connecting a resistor divider from VIN to GND with the junction at the SET pin-causing AO to sink current when input drops below threshold.

Is the ADP1111AN-3.3 pin-compatible with other variants in the ADP1111 family?

Yes-ADP1111AN-3.3 shares identical pinout and package (8-lead DIP) with ADP1111AN-5, ADP1111AN-12, and the adjustable ADP1111AN. All variants use the same ILIM, VIN, SW1, GND, SW2, FB, SET, and AO pin assignments, enabling drop-in replacement across output voltage options.