LT3690 - 36V, 4A, 1.5MHz Synchronous Step-Down Switching Regulator with 70μA Quiescent Current
- Wide Input Range:
– Operation from 3.9V to 36V
– Overvoltage Lockout Protects Circuits Through 60V Transients
- 4A Maximum Output Current
- Integrated 30mΩ N-Channel Synchronous Switch
- Low Ripple (<15mVP-P) Burst Mode® Operation:
IQ = 70μA at 12VIN to 3.3VOUT
- Programmable Input Undervoltage Lockout
- 0.8V Feedback Reference Voltage
- Output Voltage: 0.8V to 20V
- Programmable and Synchronizable Oscillator
(170kHz to 1.5MHz)
- Soft-Startup and Output Voltage Tracking
- Short-Circuit Robust
- Power Good Flag
- Small Thermally Enhanced 4mm × 6mm QFN Package
The LT3690 is an adjustable frequency monolithic buck switching regulator that accepts input voltages up to 36V. A high efficiency 90mΩ switch is included on the device along with the boost diode and the necessary oscillator, control, and logic circuitry. The internal synchronous power switch of 30mΩ increases efficiency and eliminates the need for an external Schottky catch diode. Current mode topology is used for fast transient response and good loop stability. Shutdown reduces input supply current to less than 1μA. The low ripple Burst Mode maintains high efficiency at low output currents while keeping output ripple below 15mV in typical applications.
The LT3690 features robust operation and is easily configurable. Using a resistor divider on the UVLO pin provides a programmable undervoltage lockout. A power good flag signals when VOUT reaches 90% of the programmed output voltage. Protection circuitry senses the current in the power switches to protect the LT3690 against short-circuit conditions. Frequency foldback and thermal shutdown provide additional protection. The LT3690 is available in a 4mm × 6mm QFN package with exposed pads for low thermal resistance.
PackagingFor complete and up to date package information and drawings, please refer to our packaging page
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- 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
|Part Number||Package||Pins||Temp||Price (1-99)||Price (1k)*||RoHS Data|
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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.
|DC1520A||LT3690EUFE Demo Board u 4.5V VIN 36V, VOUT = 36V @ 4A, Fsw=450kHz||$150.00|
- Automotive Systems
- Industrial Supplies
- Distributed Supply Regulation
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