LT1939 - Monolithic 2A Step-Down Regulator Plus Linear Regulator/Controller
- Wide Input Range: 3V to 25V
- Short-Circuit Protected Over Full Input Range
- 2A Output Current Capability
- Adjustable/Synchronizable Fixed Frequency Operation from 250kHz to 2.2MHz
- Soft-Start/Tracking Capability Output Adjustable Down to 0.8V
- Adjustable Linear Regulator/Driver with 13mA Output Capability
- Power Good Comparator with Complementary Outputs
- Low Shutdown Current: 12μA
- Thermally Enhanced 3mm × 3mm DFN Package
AEC-Q100 data available for specific packages
DescriptionThe LT1939 is a current mode PWM step-down DC/DC converter with an internal 2.3A switch. The wide input range of 3V to 25V makes the LT1939 suitable for regulating power from a wide variety of sources, including automotive batteries, industrial supplies and unregulated wall adapters.
Resistor-programmable 250kHz to 2.2MHz frequency range and synchronization capability enable optimization between efficiency and external component size. Cycle- by-cycle current limit, frequency foldback and thermal shutdown provide protection against a shorted output. The soft-start feature controls the ramp rate of the output voltage, eliminating input current surge during start-up, and also provides output tracking.
The LT1939 contains an internal NPN transistor with feedback control which can be conﬁgured as a linear regulator or as a linear regulator controller.
The LT1939’s low current shutdown mode (<12μA) enables easy power management in battery-powered systems.
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.
|DC1293A||LT1939EDD | Monolithic 2A Step-Down Regulator Plus Linear Regulator/Controller||Contact Factory|
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 Battery Regulation
- Industrial Control
- Wall Transformer Regulation
- Distributed Power Regulation
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