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VaLi_4706876
Level 1
Level 1
5 replies posted First reply posted First question asked

Hi, I use CY4532-EVK as a power adapter, I supply power to j2, connect it to macbook via typeC, and 20V pulses start, after a while it stabilizes and starts charging. Why are there 20V pulses at the beginning at the output?

1 Solution
Abhilash_P
Moderator
Moderator
Moderator
25 likes received 250 replies posted 250 sign-ins

Hi,

   R5, R7, R8 and R9 are the resistors connected to gate of the provider FET. Please measure the output voltage on TP10 (Type C VBUS) to measure the bus voltage on Type C VBUS.

Please let me know if you have connected the oscilloscope probe to CH1. Since from the attached waveform graph, it is clear that the magnitude of the voltage is 5V (1V*5divisions).

 

Regards,

Abhilash P

View solution in original post

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4 Replies
Abhilash_P
Moderator
Moderator
Moderator
25 likes received 250 replies posted 250 sign-ins

Hi,

  Is it possible to share the waveform?

And can I please know if these pulses stops after the PD negotiation or is it independent of it?

 

Regards,

Abhilash P

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VaLi_4706876
Level 1
Level 1
5 replies posted First reply posted First question asked

Hi, it does not depend on PD negotiation. I'll try to show the oscillogram later

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VaLi_4706876
Level 1
Level 1
5 replies posted First reply posted First question asked

I measure on R8

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Abhilash_P
Moderator
Moderator
Moderator
25 likes received 250 replies posted 250 sign-ins

Hi,

   R5, R7, R8 and R9 are the resistors connected to gate of the provider FET. Please measure the output voltage on TP10 (Type C VBUS) to measure the bus voltage on Type C VBUS.

Please let me know if you have connected the oscilloscope probe to CH1. Since from the attached waveform graph, it is clear that the magnitude of the voltage is 5V (1V*5divisions).

 

Regards,

Abhilash P

0 Likes