DC607A

LINEAR TECHNOLOGY  DC607A  演示板, LTC3722 全桥控制器

demonstration board is an isolated full bridge converter featuring LTC3722, LTC4440, LTC3901, and LT1431. This circuit was designed to demonstrate phase shifted full bridge power supply to generate 12V at 35A from a typical telecom input voltage range of 36 to 72V. The LTC3722 synchronous dual mode phase modulated full bridge controller is used on the primary and works together with LTC3901 secondary side synchronous driver to provide a synchronous rectified output. When input voltage is applied, LTC3722 begins a controlled soft start of output voltage. As this voltage begins to rise, LT1431 programmable reference is quickly powered up via the output voltage. The LT1431 provides feedback via optocoupler to set output voltage at 12V. The LTC4440 high voltage gate driver is used to level shift the high side primary MOSFETs gate signals. The LTC3722 provides precise control of gate signals to primary MOSFETs and secondary MOSFETs. DC607A has options to implement adaptive timing.

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Adaptive or manual delay control for zero voltage switching operation

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Adjustable synchronous rectification timing for highest efficiency

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Current mode operation

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Soft start, cycle by cycle current limiting and hiccup mode short circuit protection

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Drives standard threshold MOSFETs

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Programmable timeout

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Reverse inductor current sense

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Gate drive transformer synchronization sequence monitor

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Undervoltage lockout

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Fast turn on reference