Contents
What does dead time mean in a DC to buck converter?
Dead time in Synchronous Buck converter. During dead time of any DC-DC converter both the switches are turned off to avoid any shoot-through current. But in a synchronous Buck converter that would mean sudden zero current through inductor.
How to calculate power stage of synchronous buck converter?
This application note gives the formulas to calculate the power stage of a synchronous buck operating in continuous conduction mode. A synchronous buck converter produces a regulated voltage that is lower than its input voltage and can deliver high current while minimizing power loss.
How to calculate the duty cycle of a buck converter?
Equation (3-1) can be used to calculate the duty cycle, beginning with the inductor ripple during the on time and off time and using equation (3-5) : where VDS Q2 is the voltage drop across the low side MOSFET Q2 while it is on, setting , and substituting Equations 3-9, 3-10, and 3-11, the duty cycle becomes :
How to calculate minimum inductance for buck converter?
Calculating Minimum Inductance: Inductor current ripple is defined as the peak to peak change in current during the on and off time. For the synchronous buck converter, the change in inductor current during the high side MOSFET Q1 on time is equal to the change during the MOSFET’s off time.
When to use synchronous buck converters in ZVS mode?
Synchronous buck converters, typically used for front end pre-regulation in wide input DC-DC brick converters, also switch the low side MOSFET in ZVS mode. While the hard switched bridges and boost converters do not have critical dead time requirements, all soft switched ZVS bridges and synchronous buck converters must operate within such limits.
How does a synchronous buck converter work in BCM?
All in all, Synchronous Buck is all about reducing the forward losses on the Buck diode. There is no change on the operation states of the converter itself. It will work in CCM, BCM and DCM given that you have the right dead-time. Any inductor current is carried somewhere, for a while.
How is output capacitance loss calculated in a buck converter?
Output capacitance loss in the MOSFET In each switching cycle, the loss is generated because the output capacitances of the high-side and low-side MOSFETs are charged. This loss is calculated with the following equation. 2 (× = 1 −