About the power sequence in FM4

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SuSh_1535366
Level 5
Level 5
Distributor - Macnica (Japan)
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Hello.
I have three questions about the power supply sequence of the S6E2H.

1. The datasheet only mentions "VCC -> AVCC -> AVRH" as the power-on sequence.
    Does this mean that at the moment VCC exceeds VDH (reset release voltage), AVCC should be at a voltage below VCC?
    Or does it mean that AVCC must not exceed the voltage of VCC during the entire rising slope of the power supply?

2. When the reset signal is controlled externally, is it acceptable to turn on VCC only, then release the reset, and then turn on AVCC and AVRH?
    (VCC on->Reset release->AVCC on->AVRH on)

3. Is it possible to cause physical damage to the chip when performing AD conversion without power supplied to AVCC/AVRH?
    (I am aware that AD conversion cannot be performed normally. Please let me know if the chip can be destroyed.)

 

Regards,
Shimamura

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Roy_Liu
Moderator
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First comment on KBA 10 questions asked First comment on blog

Dear Shimamura,

  1. It suffices for VCC to reach the operating voltage earlier than AVCC regardless of VDH.
  2. Yes. You can set a reset release between VCC and AVCC.
  3. This operation is NOT covered by warranty, but we think the chip will be physically NOT damaged by this operation.

 

Roy Liu

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Roy_Liu
Moderator
Moderator
Moderator
First comment on KBA 10 questions asked First comment on blog

Dear Shimamura,

  1. It suffices for VCC to reach the operating voltage earlier than AVCC regardless of VDH.
  2. Yes. You can set a reset release between VCC and AVCC.
  3. This operation is NOT covered by warranty, but we think the chip will be physically NOT damaged by this operation.

 

Roy Liu
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