driving high and low side mosfet for synchronous buck converter?

Thread Starter

Fahad Fahad

Joined Mar 29, 2019
17
I am designing MPPT charge controller. I have chosen my mosfets to be both nmos https://www.sparkfun.com/products/10213 (FQP30N06L) 60V, 30A. Since the gate voltage is 3 to 5V. I can drive the low side from an arduino, however, how can drive the high side ? since Vg should be higher than Vs, which in this case is Dvin (around 37 V). A lot of people say using a half bridge driver. But also there is a problem. The output voltage is present always (battery voltage), which causes a problem for the driver.

any suggestion?
 

danadak

Joined Mar 10, 2018
3,682

Ylee5763

Joined Sep 23, 2015
27
it will not be efficient to design your own gate driver for syn buck converter because you will need a charge pump for up fet. I suggest you to use an integrated gate driver for your applications.
 

Thread Starter

Fahad Fahad

Joined Mar 29, 2019
17
What is you PWM freq ?

Generally speaking you need a gate driver for MOSFETs because
Arduino/CMOS UP cannot handle fast rise/fall times due to MOSFET
gate C and miller effect. This causes a lot of Pdiss in MOSFET gate
and drain losses due to time spent in active region.

https://www.infineon.com/dgdl/mosfet.pdf?fileId=5546d462533600a4015357444e913f4f

https://www.vishay.com/docs/73217/an608a.pdf

https://toshiba.semicon-storage.com/info/docget.jsp?did=59460



Regards, Dana.
Thank you Dana for your reply. but if I have parameters such as maximum current through these two mosfets, switching frequency (50-70kHz), arduino pin voltage , max input voltage, and max blocking voltage. is it enough to find a driver and power mosfets.
 

Thread Starter

Fahad Fahad

Joined Mar 29, 2019
17
it will not be efficient to design your own gate driver for syn buck converter because you will need a charge pump for up fet. I suggest you to use an integrated gate driver for your applications.
Thank you for your reply. I have the design parameters, but I really stuck in what to choose for the mosfet driver and power mosfets.
 

mvas

Joined Jun 19, 2017
538
I am designing MPPT charge controller.
I do not see any design.
I do not see any schematic.
Do you have any electrical engineering experience designing a 30 Amp Synchronous Buck Converter ( ie Power Electronics ) ?
Do you have any electrical engineering experience designing Printed Circuit Boards and component layout?

A lot of people say using a half bridge driver. But also there is a problem. The output voltage is present always (battery voltage), which causes a problem for the driver.
So, tell us exactly what is the "problem" with using a Half-Bridge Driver?

any suggestion?
The IR2140 Half-Bridge Driver is a possibility.

10 Amps @ 36 Volts ...
http://www.electronics-lab.com/project/half-bridge-driver-based-on-ir2104/

30 Amps @ 60 Volts ...
http://www.electronics-lab.com/project/high-current-discrete-half-bridge-based-ir2104-ir2101/


Have you decided what to do if your circuit crosses over from CCM, to DCM ?
Also, WHY did you decide to use only a Buck Converter and not a Buck-Boost Converter?
 
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