LTC3854 - Small Footprint, Wide VIN Range Synchronous Step-Down DC/DC Controller
- Wide Operating VIN Range: 4.5V to 38V
- RSENSE or DCR Current Sensing
- ±1% 0.8V Reference Accuracy Over Temperature
- 400kHz Switching Frequency
- Dual N-channel MOSFET Synchronous Drive
- Very Low Dropout Operation: 97% Duty Cycle
- Starts Up Into Pre-Biased Output
- Adjustable Output Voltage Soft-Start
- Output Current Foldback Limiting (Disabled During Soft-Start)
- Output Overvoltage Protection
- 5V LDO for External Gate Drive
- OPTI-LOOP® Compensation Minimizes COUT
- Low Shutdown IQ: 15μA
- Tiny Thermally Enhanced 12-Pin 2mm × 3mm DFN and MSOP Packages
AEC-Q100 data available for specific packages
The LTC3854 is a high performance synchronous stepdown switching DC/DC controller that drives an all N-channel synchronous power MOSFET stage.
The LTC3854 features a 400kHz constant frequency current mode architecture. The LTC3854 operates from a 4.5V to 38V (40V absolute maximum) input voltage range and regulates the output voltage from 0.8V to 5.5V.
The RUN/SS pin provides both soft-start and enable features. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. Current foldback limits MOSFET dissipation during short circuit conditions. Current foldback functions are disabled during soft-start.
The LTC3854 has a minimum on-time at 75ns, making it well suited for high step-down ratios. The strong onboard MOSFET drivers allow the use of high power external MOSFETs to produce output currents up to 20A.
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.
|DC1271A||LTC3854EDDB Demo Board | 4.5V ≤ VIN ≤ 14V, VOUT = 1.5V @ 15A||$100.00|
|DC1450A||LTC3854EDDB Demo Board | 4.5V ≤ VIN ≤ 26V, VOUT = 2.5V @ 5A||$100.00|
|DC1487A||LTC3854EMSE Demo Board | 4.5V ≤ VIN ≤ 34V, VOUT = 2.5V @ 12A||$100.00|
Designed for Automotive and Transportation ApplicationsAEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page
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- Automotive Systems
- Telecom Systems
- Industrial Equipment
- Distributed DC Power Systems
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