L6230Q VFQFPN32 High Side Voltage Drop = 2.6V

[s61331]

Posted on February 08, 2017 at 15:03

Hello,

i our Motor Control Board with FOC i have very high losses in the Driver IC L6230Q in the VFQFPN package.

In the On-Time of the High side i have a differenz of 2.6V between the Operatine Voltage (21V) and the Output Voltage on the Motorphase. (see picture)

Channel 2 (blue) = Opperating Voltage

Channel 1 (yellow) = Out 2

measured direktly on the pins of the L230

One of the other Phase is Low (Low-Side On) and the third one is Open (EN is low)

With the thermo camera i can see hot points (>100°C) in the chip. so there is no bad soldering.

The schematic is equal to the datasheet.

With the P-Nucleo IHM001 i dont have this high losses. On this Board the L6230Q is in the big PowerSO36 Package

Anyone ideas?

Thank You

Eric

[Enrico Poli]

Posted on February 10, 2017 at 10:28

Hello,

How much is the current you are sinking from the output?

Did you checked the BOOT voltage is ok?

Enrico

[s61331]

Posted on February 10, 2017 at 11:59

The current is under 1A

Currently the Driver is broken and i have to replace it. The charge Pump doesnt work anymore and the Driver is getting very hot.

The other Driver on the other boards doestn have this problem. But they have more losses then the eval board and more losses then the old driver we use (L6229).

I wanted ti find the fault why there are mor losses and found the 2.6V. But  think it was just one driver with this issue.

I will measure the Energie consumption of 4pc boards with the L6229 board and 4pc of the L6230 Boards.

[Enrico Poli]

Posted on February 10, 2017 at 14:34

For sure the damaged charge pump is the root cause of the anomalous drop on the high side MOSFET.