UCC21225A: Same Supply for Both Output Stages?

Pranit Pawar1

Part Number: UCC21225A
Other Parts Discussed in Thread: UCC5350, ISO5451

Hi Experts,

This is regarding any UCCxxxx dual (HS+LS) channel isolated gate driver.

I'm thinking of implementing an external miller clamp (to get stronger GS pulldown) in my half-bridge circuit, using a dual ch driver. Can I short the supply pins of both output stages, use HS output to drive the switch and the complementary LS output to drive the miller clamp? (refer to fig.)

I'm aware of the fact that this destroys the purpose of channel-channel isolation, but apart from this, will supplying HS+LS from same supply cause any issue in driver functioning? Will the output stages give output according to their corresponding input (VIA, VIB) ?

Regards,

Pranit

over 3 years ago

0 Krystian Plaskota over 3 years ago

TI__Expert 4065 points

Hi Pranit,

Can you reupload your image?

Thanks,

Krystian

0 Pranit Pawar1 over 3 years ago in reply to Krystian Plaskota

Prodigy 50 points

0 Krystian Plaskota over 3 years ago in reply to Pranit Pawar1

TI__Expert 4065 points

Hi Pranit,

This configuration is acceptable, I don't see any problem with this. However, maybe consider looking at the UCC5350, it has a built in miller clamp.

Regards,

Krystian

0 Pranit Pawar1 over 3 years ago in reply to Krystian Plaskota

Prodigy 50 points

Thanks!

I'd like to simulate the driver behaviour in above stated configuration. Will driver's pspice model simulate this behaviour?

Also, PSpice_TI keeps on giving me an error - LMC-02955 (License call failed for feature PSpice_TI, version 17.400 and quantity 1. License server search path is defined as C:\........... . An internal error occured)
Probably something to do license.txt file in the above location. I checked the license.txt file and its empty.

I'd appreciate help in above two. Thanks

0 dimitri james over 3 years ago in reply to Pranit Pawar1

TI__Genius 10652 points

Pranit Pawar1 said:

I'd like to simulate the driver behaviour in above stated configuration. Will driver's pspice model simulate this behaviour?

Yes, it will work. but as Krystian suggested, if you actually want to use miller clamp in a production design you would be best served by UCC5350 (or ISO5451 with has one extra feature). Miller clamp activates based on gate voltage, but in your configuration, you would have to play with timing without knowing what the gate voltage was.

License issue with PSPICE is not uncommon, recommend you to fully uninstall it and resinstall a fresh copy from here https://www.ti.com/tool/PSPICE-FOR-TI

(even version 17.4 has several revisions, so get latest copy). Please try the simulatin again after.

If still not working, please post in the Simulation forum, an expert on PSPICE for TI can assist with fixing that issue. Link to forum below.

https://e2e.ti.com/support/tools/sim-hw-system-design/f/234

I did a quick search and found several others with this issue,

Please find this thread with same error code: https://e2e.ti.com/support/tools/sim-hw-system-design/f/234/t/935185?tisearch=e2e-sitesearch&keymatch=LMC-02955

Best

Dimitri

Power management

Power management forum

UCC21225A: Same Supply for Both Output Stages?