I am using the gate driver ADuM4223ARWZ for ongoing applications.
Kindly refer to my previous thread where we had discussed many technical issues.
Now, I have come up with a new requirement to drive TWO no of MOSFETs(P/N : VS-FC220SA20) using single PWM,as shown in the below image.
Before proceeding,I just want to confirm whether it is recommended to drive Two different MOSFETs with single PWM using Boot strapped gate driver ADuM4223.
The source connections for both the MOSFETs are common.I need to drive both the MOSFETs simultaneously with single PWM.
Will there be any issues while driving such SOT 227 Die package MOSFETs?
Kindly provide your suggestions.
Because the GNDA and GNDB are connected, you won't need D1 and R1. The bootstrap configuration is only required if there is a need to create a high side power supply. Since both channels are referenced to the same ground, they can use the same power supply (+15V_L).
Pins 9-11 and pins 14-16 both have the same silicon die inside the part. Using iCoupler isolation, both output stages are similar. There is no issue operating the two output regions in parallel like you have shown.
I do have one question about the schematic. For the bus voltage (+VE and -VE) is +VE the positive voltage? If so, would the bus voltage go through the MOSFET body diode as drawn right now?
Hello RSchnellThanks so much for your clear explanation.Following to your suggestion,1, The pins 1 & 2 are hard paralleled/shorted together in our schematic.Will there be any issues?2, Pls check the revised schematic as per your guidelines and confirm the same. Here,The pins VDDA and VDDB are sharing the same power supply +15V_L.
3, Regarding your question-would the bus voltage go through the MOSFET body diode as drawn right now?
Actually this is a clamp circuit which will be used along with full bridge circuit.The voltage across the bridge will be clamped to clamp capacitor voltage.This happens during commutation interval.The clamp capacitor is charged & discharged periodically and the operation is strongly influenced with associated bridge circuit.Awaiting your response for (1) & (2) to freeze our design.regards,Ramesh P
1) Pins 1 and 2 can be shorted together. They are both inputs, and there is no problem having them trigger at the same time.
2) The schematic looks good to me. As long as the 15V_L is referenced to +VE and is a floating supply, this will work well.
3) Thanks for the info.
Thanks a lot for your suggestions and inputs.
Also,sorry for my delayed response.
I just want to update my another design using Bootstrap Isolated gate driver (for Power MOSFETs) with inbuilt features such as Vce(sat) detection,active clamp,fault output.Is there any single IC pack available from ANALOG DEVICES with integrated Vce detection, active miller clamp, fault output feature in addition to what gate driver IC ADuM4223 does?
Kindly suggest me a better solution,if available.
ADI has a large offering of isolated gate drivers. We don't have a dual channel driver that includes Desat, active Miller clamp, and fault output, but we do have single channel devices that include that. The first part to look at would be the ADuM4135 which includes all of those functions.
More advanced drivers include the ADuM4137 and ADuM4138.
The ADuM4138 includes a flyback controller for easier system building. Both the ADUM4137 and ADuM4138 include fault reporting. The ADuM4138 includes Desat detection. They are more complex drivers that include remote temperature sensing and overcurrent detection for split emitter type power devices.
If Desat and Miller clamping is required on a two channel part, the pin count gets really large, and we find that layout is much easier with two separate devices.
All of these can be used in a bootstrap configuration if desired.
I hope this helps,
Thank you very much for your detailed reply.
I will go through the datasheets and come back to you for any clarifications.