Volts!
Phew!
After much fiddling and faffing and going bozzeyed, we have some voltage measurements (see attached table).
Pin (number) and (pin) name should be self explanatory. The TP after the pin name indicates a point on the circuit where is is slightly easier to measure with elephantine multimeter probes. I found these by inspecting the traces, checking continuity to the appropriate pin and checking measurements at both pints. A and K are anode and cathode respectively for a diode. For the capacitors, us the end connected to the pin by inspecting the traces.
Note also I used a digital multimeter which is sluggish in response, so some of the voltages could not be accurately measured before the chip went from active to standby mode.
Just to recap:
Sleep corresponds to eReader powered down
Standby corresponds to eReader in sleep, or after failing to boot (in this case)
Active corresponds to the eReader at power-up and before the chip reverts to standby (after two or three seconds).
Also attached is the application example circuit from the datasheet which, unsurprisingly, is almost identical to that on the board. The test points have been added in for reference.
Last edited by DomesticExtremis; 10-02-2019 at 08:21 PM.
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