UCC256403: Conditions under which the internal LDO is enabled

Kaji@PAN

Part Number: UCC256403

Hello,

I would like to ask you about the internal LDO of the UCC256403.
Looking at the block diagram in the data sheet, the RVCCEn signal must be input to the LDO to enable the internal LDO.

What are the conditions under which RVCCEn is enabled?
Does VCC satisfy the condition of VCCStartSwitching = 10.9V?

Also, is it possible to operate the device with the internal LDO enabled even if 12V is applied to VCC?

Best regards,

over 3 years ago

0 Manikanta Pallantla over 3 years ago

TI__Genius 16155 points

Hi,

RVCCEn signal is the input to the LDO to enable the internal LDO. RVCC is enabled as soon as VCC reaches VCCStartSwitching which is 10.9V.

LDO output voltage is as below:

1. output voltage is same as input voltage when input voltage to the LDO is less than 13V.

2. Output voltage will be regulated at 13V when the input voltage to the LDO is more than 13V

As per above mentioned conditions, it is possible to operate the LDO when the VCC is 12V.

Regards

Manikanta P

0 Kaji@PAN over 3 years ago in reply to Manikanta Pallantla

Mastermind 7775 points

Thank you for your reply.
I have one more question.
There is a description of AVDD in the block diagram of the data sheet. Is AVDD supplied from RVCC?
Or is AVDD a completely different voltage?

Best regards,

+1 Manikanta Pallantla over 3 years ago in reply to Kaji@PAN

TI__Genius 16155 points

Hi,

AVDD is an internal voltage rail that is separate from RVCC. This is an internal voltage rail supplying the internal circuit.

Regards

Manikanta P

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UCC256403: Conditions under which the internal LDO is enabled