Hardware: Bidirectional TVS symbol is misleading

softerhardware / Hermes-Lite2

A second generation low-cost amateur HF software defined radio transceiver.

http://www.hermeslite.com

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Hardware: Bidirectional TVS symbol is misleading #72

Closed in3otd closed 6 years ago

in3otd commented 6 years ago

The symbol for the SMBJ18CA (D12) and the CDSOD323-T05LC (D1) are a bit misleading, they should represent two diodes in "antiseries", like here. BTW, I'm not sure that D12 should be a bidirectional diode, even if negative voltages will be blocked by Q1, maybe we could use an unidirectional protection there.

softerhardware commented 6 years ago

http://datasheet.octopart.com/CDSOD323-T05LC-Bourns-datasheet-13385636.pdf is slightly different.

in3otd commented 6 years ago

yes and maybe closer to the actual internal design but the complete circuit does not fit well in a schematic symbol :grin: . My point was that the current symbol looks like two Schottky diodes in antiparallel so at a first glance it appears to conduct at around ±400 mV

softerhardware commented 6 years ago

Schematic symbols updated to match datasheets.