But in general, this plan seems reasonable. Cascade the 3.3V and 1.2V LDOs just so the 1.2V has less to dissipate (i.e. VBus -> 3.3V rail, 3.3V rail -> 1.2V rail).
How much are you okay trusting the controllers? Routing VBus to them directly means you're trusting them to stay within some power limit to not overdraw from the upstream USB port (well designed port will just shut off, less well made... magic smoke/other sadness?)
Dave Anderson /
npub1mt…xwant
2024-08-10 20:46:33
in reply to nevent1q…22af
Author Public Key
npub1mtg38agwglttl7melxnfqphlm95uymnrdedw62h9j7cyquynza0szxwantPublished at
2024-08-10 20:46:33Event JSON
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"content": "But in general, this plan seems reasonable. Cascade the 3.3V and 1.2V LDOs just so the 1.2V has less to dissipate (i.e. VBus -\u003e 3.3V rail, 3.3V rail -\u003e 1.2V rail).\n\nHow much are you okay trusting the controllers? Routing VBus to them directly means you're trusting them to stay within some power limit to not overdraw from the upstream USB port (well designed port will just shut off, less well made... magic smoke/other sadness?)",
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