LT3581 - 3.3A Boost/Inverting DC/DC Converter with Fault Protection
- 3.3A, 42V Combined Power Switch
- Master/Slave (1.9A/1.4A) Switch Design
- Output Short Circuit Protection
- Wide Input Range: 2.5V to 22V Operating, 40V Maximum Transient
- Switching Frequency Up to 2.5MHz
- Easily Configurable as a Boost, SEPIC, Inverting or Flyback Converter
- User Configurable Undervoltage Lockout
- Low VCESAT Switch: 250mV at 2.75A (Typical)
- Can be Synchronized to External Clock
- Can Be Synchronized to other Switching Regulators
- High Gain SHDN Pin Accepts Slowly Varying Input Signals
- 14-Pin 4mm × 3mm DFN and 16-Lead MSE Packages
AEC-Q100 data available for specific packages
The LT®3581 is a PWM DC/DC converter with built-in fault protection features to aid in protecting against output shorts, input/output overvoltages, and overtemperature conditions. The part consists of a 42V master switch, and a 42V slave switch that can be tied together for a total current limit of 3.3A.
The LT3581 is ideal for many local power supply designs. It can be easily configured in Boost, SEPIC, Inverting or Flyback configurations, and is capable of generating 12V at 830mA, or –12V at 625mA from a 5V input. In addition, the LT3581’s slave switch allows the part to be configured in high voltage, high power charge pump topologies that are very efficient and require fewer components than traditional circuits.
The LT3581’s switching frequency range can be set between 200kHz and 2.5MHz. The part may be clocked internally at a frequency set by the resistor from the RT pin to ground, or it may be synchronized to an external clock. A buffered version of the clock signal is driven out of the CLKOUT pin, and may be used to synchronize other compatible switching regulator ICs to the LT3581.
The LT3581 also features innovative SHDN pin circuitry that allows for slowly varying input signals and an adjustable undervoltage lockout function. Additional features such as frequency foldback and soft-start are integrated. The LT3581 is available in 14-Pin 4mm × 3mm DFN and 16- Lead MSE packages.
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.
|DC1424A-A||LT3581EMSE Demo Board | VIN= 5V to 10V, VOUT1 = 12V @ 900mA||$175.00|
|DC1424A-B||LT3581EMSE Demo Board | VIN= 5V to 12V, VOUT1 = -12V @ 750mA||$175.00|
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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- Local Power Supply
- Vacuum Fluorescent Display (VFD) Bias Supplies
- TFT-LCD Bias Supplies
- Automotive Engine Control Unit (ECU) Power
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