UCC28220-Q1: reduce the current sensing circuit to one single feedback

Stani Bell Ngoufack Tchoufack89

Intellectual 2020 points

Part Number: UCC28220-Q1
Other Parts Discussed in Thread: UCC28220, LM5032

Hello,

my customer is interested in the UCC28220-Q1 controller for an ongoing project and he would like to know if it is possible to reduce the current sensing circuit to one single feedback?

What they would like to achieve is a cost reduction: they are developing a 80KW DCDC converter and the current sense circuits for power level like this is extremely expensive, they would like to control the 2 interleaved buck using a single current sensor placed on the output (it will measure the total output current). is this feasable?

The customer has the same question for the LM5032-Q1 device.

Regards,

Stani

over 5 years ago

0 John Griffin1 over 5 years ago

TI__Mastermind 34465 points

Hello Stani,

The UCC28220 needs to be able to independently sense the switch current in each phase of the interleaved signal.
It needs to do this so that each phase is the same current value.

If you just sense the sum of the two phases then one phase may have a low current and the other phase may have a higher current.
This would mean that power is not accurately shared between the interleaved phases.

Therefor I think it is not possible to use a single a single current sensor for either the UCC28220 or the LM5032

Regards

John

0 Stani Bell Ngoufack Tchoufack89 over 5 years ago in reply to John Griffin1

TI__Intellectual 2020 points

Hello John,

thanks for your feedback. I'll share this with my customer.

Best regards,

Stani

0 Stani Bell Ngoufack Tchoufack89 over 5 years ago in reply to John Griffin1

TI__Intellectual 2020 points

Hi John,

since the power level is quite high the customer plans to use hall effect current sensors to do the current measurement and he wants to know if we see any issue in this?

Best regards,

Stani

0 John Griffin1 over 5 years ago in reply to Stani Bell Ngoufack Tchoufack89

TI__Mastermind 34465 points

Hi Stani,

Hall effect sensors are great for measuring DC and low frequency but they will not be suitable for measuring the high frequency switching current associated with the UCC28220. Current transformers come in many shapes , sizes and current ratings so it should be possible to find a suitable one for this application.

Regards

John

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UCC28220-Q1: reduce the current sensing circuit to one single feedback