LT3740 - Wide Operating Range, Valley Mode, No RSENSE Synchronous Step-Down Controller
- Wide VIN Range: 2.2V to 22V
- Internal Boost Provides 6V Gate Drive For VIN Down to 2.2V
- No Sensing Resistor Required
- Dual N-Channel MOSFET Synchronous Drive
- Valley Current Mode Control
- Optimized for High Step-Down Ratio
- Power Good Output Voltage Monitor
- 0.8V Reference
- Three Pin-Selected Current Limit Levels
- Constant Switching Frequency: 300kHz
- Programmable Soft-Start
- Output Voltage Tracking
- Available in 16-Pin 5mm × 3mm DFN
The LT3740 is a synchronous step-down switching regulator controller that drives N-channel power MOSFET stages. The controller uses valley current mode architecture to achieve very low duty cycles with excellent transient response without requiring a sense resistor.
The LT3740 includes an internal step-up converter to provide a bias 7.8V higher than the input voltage for the drive. This enables the part to work from an input voltage as low as 2.2V.
The XREF pin is an external reference input that allows the user to override the internal 0.8V feedback reference with any lower value, allowing full control of the output voltage during operation, output voltage tracking or soft-start.
The LT3740 has three current limit levels that can be chosen by connecting the RANGE pin to ground, open, and input respectively.
CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.
For complete and up to date package information and drawings, please refer to our packaging page
- Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
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Demo BoardsLinear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
|DC947A||LT3740EDHC Demo Board||$125.00|
- Notebook and Palmtop Computers, PDA
- Portable Instruments
- Distributed Power Systems
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