[Arm-netbook] help needed with a ttl logic circuit

Luke Kenneth Casson Leighton lkcl at lkcl.net
Sun Aug 23 15:52:27 BST 2015

ok so i redid it, using a darlington pair, because yes the voltage
definitely needs to be below 0.69v at the output:  also, forget about
the "disconnected" operation, that can be done with a jumper.


still don't feel completely happy (esp. with the schottky diode), i
feel another transistor might be needed especially because VREFTTL
(for the EOMA68_BOOT0 TTL level) could be *lower* than 3.3v.


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