Features and Benefits
- Dual, 180° Phased Controllers
- 2-Pin VID Output Voltage Programming from 0.6V to 5V
- High Efficiency: Up to 95%
- RSENSE or DCR Current Sensing
- Phase-Lockable Fixed Frequency 250kHz to 770kHz
- Adjustable Current Limit
- Dual N-Channel MOSFET Synchronous Drive
- Wide VIN Range: 4.5V to 38V Operation
- Adjustable Soft-Start Current Ramping or Tracking
- Output OV Protection With Reverse Current Limit
- Power Good Output Voltage Monitor
- 32-Pin 5mm × 5mm QFN and 38-Lead TSSOP Packages
The LTC3865/LTC3865-1 are high performance dual synchronous step-down DC/DC switching regulator controllers that drive all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 770kHz. Power loss and noise are minimized by operating the two controller output stages out of phase.
OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. Independent track/soft-start pins for each controller ramp the output voltage during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode® operation, pulse-skipping mode, and continuous inductor current mode. The output voltages can be precisely programmed by pin strapping or external resistors.
The LTC3865/LTC3865-1 are available in low profile (5mm × 5mm) 32-pin QFN and 38-Lead thermally enhanced TSSOP packages.
- DC Power Distribution Systems
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 (2)
Demonstration circuit 1480A is a dual output synchronous buck DC/DC converter featuring the LTC3865EUH-1. The input voltage range is from 4.5V to 14V. The default outputs are 3.3V/5A and 1.8V/5A, but pin programming allows each output to be set at 5V, 3.3V, 2.5V, 1.8V, 1.5V, 1.2V, 1.1V, 1V or an adjustable voltage.
Demonstration circuit 1479A is a dual output synchronous buck DC/DC converter featuring the LTC3865EUH. The input voltage range is from 4.5V to 14V. The outputs are 1.5V/15A and 1.2V/15A. Each output voltage can be precisely programmed to a preset value within 1% error using two 3-state programming pins. The output voltage can be set to 1.0V, 1.1V, 1.2V, 1.5V, 1.8V, 2.5V 3.3V or 5V. The LTC3865 differs from the LTC3865-1 in that the "-1" has a fixed current limit threshold. The 32-pin package options for both devices have no SGND pin and only one PGND pin.
Tools & Simulations
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.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
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.
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.