Overview
Features and Benefits
- Tiny Surface Mount, Low Profile 3mm × 4mm × 1.18mm LGA Package and 3mm × 4mm × 1.48mm BGA Package
- Input Voltage Range: 2.25V to 3.6V
- Dual 2A DC Output Current
- ±1.5% Total Output Voltage Regulation
- Current Mode Control, Fast Transient Response
- External Frequency Synchronization
- 180° Out-of-Phase Operation
- Selectable Pulse-Skipping Mode/Burst Mode® Operation/Forced Continuous Mode
- Power Good Indicator
- Internal Soft-Start
- Internal Compensation
- Overvoltage, Overcurrent and Overtemperature Protection
Product Details
The LTM4691 is a complete dual 2A output switching mode DC/DC power supply in a tiny 3mm × 4mm × 1.18mm LGA package and a 3mm × 4mm × 1.48mm BGA package. Included in the package are the switching controller, power FETs, inductors and all supporting components. Operating over an input voltage range of 2.25V to 3.6V, the LTM4691 supports two outputs with programmable output voltage range from 0.5V to 2.5V set by external resistors. Its high efficiency design delivers up to 2A continuous current on each output. Only bulk input and output capacitors are needed.
The LTM4691 operates in forced continuous mode for low noise pulse-skipping mode or Burst Mode operation for high efficiency at lights loads. The typical buck switching frequency is 2MHz and can be synchronized from 1MHz to 3MHz. Its high switching frequency and a current mode architecture enables a very fast transient response to line and load changes without sacrificing stability.
Other features include precision run thresholds, a PGOOD signal, output overvoltage protection, thermal shutdown and output short-circuit protection. The LTM4691 is Pb-free and RoHS compliant.
Applications
- Telecom, Networking and Industrial Equipment
- Point-of-Load Regulation
- FPGA, ASIC Core Supplies
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Documentation
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

Models for the following parts are available in LTspice:
LTpowerCAD
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.

Design tools for the following parts are available in LTpowerCAD:
Reference Materials
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
PCN-PDN Information
Support & Discussions
LTM4691 Discussions
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.