Driving CoolGaN with EiceDriver

[User18242]

I have attached the circuit. I'm trying to drive a coolgan HEMT (IGOT60R070D1) with driver - 1EDF5673F.

PROBLEM - 1) When I tested the driver alone (without connecting the switch and the power circuit), the driver always shows -8V as output at the "gate to source terminal" irrespective of what I give at the PWM input pin.

PROBLEM - 2) When I soldered the gan switch, the SK pin of the switch draws considerably high current (more than 200-300mA). (drive still gives -8V between G-SK of device)

Can anyone help with this problem? What am I missing?

PS: I have soldered two boards with new components to confirm the above symptoms. So i'm sure its not the soldering issue or damaged ICs.

[vinc]

It looks like the input side you are using a 5V VDDI solution as evaluation board application note.

As you are using a 3.3 VDDI, SLDO should be grounded to disable the shunt LDO voltage regulator and 470ohm shunt resistor should be removed as descibed in datasheet as below.




I would assume the main reason would be the input side of 1EDF5673K is not correctly supplied so that you only have -8V output as no switching activity.


If you have a voltage higher than 3.5V as in application note (5V), you can find the reason in datasheet below.

[User18242]

Hello Vinc, thank you for your response.

You correctly identified the cause of the first problem. Using a 5V supply on the input side of the driver did solve the problem. - PROBLEM-1 SOLVED - USE 5V for VDDI WHEN SLDO IS GROUNDED.

[User18242]

One serious note about 1EDF5673 - IT IS A FULL BRIDGE DRIVER - hence, you can NOT short the driver ground with the source of the switch. - So, an ISOLATED DRIVER SUPPLY IS MUST with 1EDF5673 even if you just want to make a simple boost converter.

If you are using half-bridge driver like 1EDI20NAF, YOU CAN short the driver ground with the source of the switch - so isolated supply not required.

Refer to follwing images from infineon showing these circuits:




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This justifies the PROBLEM-2 in the original post. I was not using an isolated supply.

[AZIZ_HASSAN · Accepted solution]

Hi,

For problem number 2 if you try with different gate resistor and share us the current consumption result, then I think we can comment on that.

BR,

AZIZ HASSAN