Humpback errata - Githubissues

sinara-hw / Humpback

General purpose STM32/ESP32/OrangePi/Beaglebone baseboard with FPGA and 2 downstream / 1 upstream EEM ports

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Humpback errata #7

Open gkasprow opened 5 years ago

gkasprow commented 5 years ago

[ ] Pull R166 to P12V0 instead of P3V3, optionally add R to GND
[ ] make sure IC2 and IC3 are supplied from 12V via LDO or parallel Zener-based regulator
[ ] use lower dropout LDO for 2.5V or connect to 5V0
[ ] 3.3V LED too bright

kaolpr commented 4 years ago

@gkasprow What do you mean by "add R to GND"?

gkasprow commented 4 years ago

@kaolpr just make voltage divider between 12V and GND that gives 3.3V. For the moment, to fix v1.0 remove R170 and R160 and connect pin 38 of IC87 via 10k to +12V obraz

In the next revision make sure IC2 and IC3 are supplied from 12V via parallel Zener-based regulator.

gkasprow commented 4 years ago

For rev 1.0 just cut the polygon and connect the LDO input to 5V rail. After cutting, make sure the polygon is really isolated. obraz

gkasprow commented 4 years ago

Optionally, one can lift pin 3 of IC4 and connect it to C244 without cutting the polygon.

jordens commented 4 years ago

@kaolpr is this for a new batch of v1.0 or a new revision?

gkasprow commented 4 years ago

TS produced more v1 boards and need to implement these fixes manually