Overview
Features and Benefits
- Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 14V
- Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
- OPTI-LOOP® Compensation Minimizes COUT
- ±1% Output Voltage Accuracy
- Power Good Output Voltage Monitor
- Phase-Lockable Fixed Frequency 250kHz to 550kHz
- Dual N-Channel MOSFET Synchronous Drive
- Wide VIN Range: 4V to 36V Operation
- Very Low Dropout Operation: 99% Duty Cycle
- Adjustable Soft-Start Current Ramping
- Foldback Output Current Limiting
- Output Overvoltage Protection
- Low Shutdown IQ: 20µA
- Selectable Constant Frequency or Burst Mode® Operation
- Small 28-Lead SSOP Package
Product Details
The LTC3727A-1 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows phase-lockable frequency of up to 550kHz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages out of phase.
The LTC3727A-1 is an improved version of the LTC3727 family of parts. It has smaller output ripple while in the drop-out condition and shorter minimum on-time.
OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. There is a precision 0.8V reference and a power good output indicator. A wide 4V to 30V (36V maximum) input supply range encompasses all battery chemistries.
A RUN/SS pin for each controller provides soft-start. Current foldback limits MOSFET heat dissipation during short-circuit conditions. Output overvoltage protection circuitry protects the controller until VOUT returns to normal.
VIN Range | VREF Accuracy Over Temp | Latch-Off | Min On-Time | |
LTC3727 | 4V - 36V | ±1% | No | 180ns |
LTC3727-1 | 4V - 36V | ±1% | Yes | 180ns |
LTC3727A-1 | 4V - 36V | ±1% | No | 120ns |
LTC3727LX-1 | 4V - 32V | ±1.5% | No | 120ns |
Applications
- Telecom Systems
- Automotive Systems
- Battery-Operated Digital Devices
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation
Reliability Data (1)
User Guides (1)
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:
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.
Support & Discussions
LTC3727A-1 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.