LTC3649 - 60V, 4A Synchronous Step-Down Regulator with Rail-to-Rail Programmable Output
- Wide VIN Range: 3.1V to 60V
- Wide VOUT Range: 0V to (VIN – 0.5V)
- Single Resistor VOUT Programming
- Integrated 110mΩ Top N-Channel/50mΩ Bottom N-Channel MOSFETs
- 95% Efficiency with 12VIN and 5VOUT
- Regulated IQ: 440μA, Shutdown IQ: 15μA
- Accurate Current Monitoring (±4%) without Sense Resistor
- Accurate Resistor Programmable Frequency (300kHz to 3MHz) with ±50% Frequency Sync Range
- Accurate Programmable Output Current
- Input Voltage Regulation for MPPT Applications
- ±0.8% Output Voltage Accuracy
- Peak Current Mode Operation
- Programmable Wire Drop Compensation
- Burst Mode® Operation, Forced Continuous Mode
- Internal Compensation and Programmable Soft-Start
- Overtemperature Protection
- Available in Thermally Enhanced 28-Lead (4mm × 5mm) QFN and TSSOP Packages
The LTC®3649 is a high efficiency 60V, 4A synchronous monolithic step-down regulator. The regulator features a single resistor programmable output voltage, internal compensation and high efficiencies over a wide VOUT range.
The step-down regulator operates from an input voltage range of 3.1V to 60V and provides an adjustable rail-to-rail output range from (VIN – 0.5V) to ground while delivering up to 4A of output current. The switching frequency is also adjusted with an external resistor. A user-selectable mode input is provided to allow the user to trade off ripple noise for efficiency at light loads; Burst Mode operation provides the highest efficiency at light loads, while forced continuous mode provides low output ripple. The MODE/ SYNC pin can also be used to allow the user to synchronize the switching frequency to an external clock.
The LTC3649 operates with a peak current mode architecture that allows for fast transient response with inherent cycle-to-cycle current limit protection. It also features programmable output current limit, current monitoring and input voltage regulation.
CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprint compatible with Mentor Graphics PADS® v9.5 or later, and Cadence ORCAD® v16.5 or later.
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.
|DC2113A||LTC3649 Demo Board | Sync Buck, 3.1V ≤ VIN ≤ 60V, Vout = 3.3V/5V @ 4A||$150.00|
- Industrial Applications
- Automotive Applications
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