Menu
Close
Overview
Features and Benefits
- Single Inductor Architecture Allows VIN Above, Below or Equal to VOUT
- Power Good Output Indicator
- 2.7V to 10V Input and Output Range
- Up to 96% Efficiency
- Up to 10A of Output Current
- All N-Channel MOSFETs, No RSENSE™
- True Output Disconnect During Shutdown
- Programmable Current Limit and Soft-Start
- Optional Short-Circuit Shutdown Timer
- Output Overvoltage and Undervoltage Protection
- Programmable Frequency: 100kHz to 1MHz
- Selectable Burst Mode® Operation
- Available in 24-Lead (4mm × 4mm) Exposed Pad QFN Package
Product Details
The LTC3785-1 is a high power synchronous buck-boost controller that drives all N-channel power MOSFETs from input voltages above, below and equal to the output voltage. With an input range of 2.7V to 10V, the LTC3785-1 is well suited for a wide variety of single or dual cell Li-Ion or multi-cell alkaline/NiMH applications.
The operating frequency can be programmed from 100kHz to 1MHz. The soft-start time and current limit are also programmable. The soft-start capacitor doubles as the fault timer which can program the IC to latch off or recycle after a determined off time. Burst Mode operation is user controlled and can be enabled by driving the MODE pin high. The LTC3785-1 includes a Power Good output that indicates when the output voltage is within 7.5% of its designed setpoint.
Protection features include foldback current limit, short-circuit and overvoltage protection.
| Power Good | |
| LTC3785 | No |
| LTC3785-1 | Yes |
Applications
- Palmtop Computers
- Handheld Instruments
- Wireless Modems
- Cellular Telephones
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.
Documentation
Reliability Data (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.
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:
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
Small Size and Very High Efficiency Buck-Boost Converter - LTC3780
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
LTC3785-1 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.