42V multitopology DC/DC controller outputs 10A

September 12, 2017 // By Graham Prophet
LT8711 is a multitopology current mode PWM controller that can be configured as a synchronous buck, boost, SEPIC and ZETA DC/DC converter, or as a nonsynchronous buck-boost converter. This device replaces the output diode with a high efficiency P-channel MOSFET, thereby increasing efficiency and maximum output current up to 10A, for automotive, industrial, solar and general purpose applications.

The LT8711 operates over a 4.5V to 42V input voltage range and produces an output voltage that is dependent on the choice of external components. The 15 μA no-load quiescent current with the output voltage in regulation extends operating run time in battery-powered systems. Low ripple Burst Mode operation enables high efficiency at very light loads while maintaining low output voltage ripple. When configured as a synchronous buck, the LT8711 can operate at 100% duty cycle, a useful feature when powered from a battery that is discharging.

The LT8711 features EN/FBIN pin circuitry for input voltage regulation to avoid collapsing a high impedance input source such as a solar panel. This pin is also used for adjustable undervoltage lockout. The fixed operating frequency is selectable from 100 kHz to 750 kHz and can be synchronized to an external clock. Additional features include dual chip power supply inputs, a topology selection pin and adjustable soft-start.

The LT8711 is available in 20-lead TSSOP and 3mm x 4mm QFN packages. Extended and industrial versions operate over a junction temperature range of –40°C to 125°C. Pricing starts at $2.30 (1000).

Analog Devices/Linear Technology; www.linear.com/product/LT8711.

 

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