3V to 65V, 5.5A Synchronous Step-Down Silent Switcher with 9μA Quiescent Current

The LT80605 step-down regulator features the Silent Switcher® architecture to minimize EMI emissions while delivering high efficiency at frequencies up to 3MHz. Assembled in a 3mm x 4mm QFN, the monolithic construction with integrated power switches and inclusion of all necessary circuitry yields a solution with a minimal PCB footprint. An ultralow 9μA quiescent current with the output in full regulation enables applications requiring highest efficiency at light loads. The device features a SYNC/MODE pin that selects among Burst Mode, pulse skipping, or forced continuous mode (FCM), and also allows synchronization to an external clock. Soft-start and tracking functionality are accessed through the TR/SS pin. An accurate enable threshold can be set using the EN/UV pin and a resistor at the RT pin programs switch frequency. In addition, the device features a PG/TJ pin that can be used either to monitor the status of output voltage or die temperature. The die temperature monitor allows to directly measure the silicon die temperature, enabling a robust, reliable power supply design.

APPLICATIONS

* General Purpose Step-Down

* Automotive and Industrial Supplies

* Silent Switcher® Architecture, Ultralow EMI Emissions

* High Efficiency at High Frequency

* Up to 94.5% at 400kHz, 24VIN to 5VOUT

* Up to 93% at 1MHz, 24VIN to 5VOUT

* Pin Selectable Adjustable, Fixed 3.3V and 5V Output

* Ultralow Quiescent Current Burst Mode Operation

* 9μA IQ Regulating 24VIN to 5VOUT

* On-the-Fly Mode Change Among Burst, Pulse Skip and Forced Continuous Mode

* Burst and Pulse Skipping Modes to Enable Enhanced Light-Load Efficiency