Schematic help
#3
Module inserted correctly. Have the green module. On the DIP122-5 I have 3.3 v on pin2 (which the data sheets says should be 5v) This pin is connected to the surface 3.3 v bus so is OK. I have 5v on pin 17 for the backlight and about 2v on pin 18 which is net negative back lite so I suspect this is for adjusting the back light brightness. The big problem seems to be on pin3 for the contrast adjustment. Data sheet says -4V which the board documents say is derived from a PWM output of the ST. I get +.9v on pin3, -.6v and -.3v as I go down the voltage multiplier. Suspect this is the problem. ?????
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Messages In This Thread
Schematic help - by Lawrence Stoskopf - 2015-02-13, 04:44
Schematic help - by DelandeC - 2015-02-13, 07:43
RE: Schematic help - by Lawrence Stoskopf - 2015-02-13, 17:34
RE: Schematic help - by Lawrence Stoskopf - 2015-02-14, 05:17
RE: Schematic help - by ing.sohaib - 2015-05-24, 20:53
RE: Schematic help - by Lawrence Stoskopf - 2015-02-16, 16:34
RE: Schematic help - by DelandeC - 2015-02-16, 17:16
RE: Schematic help - by Lawrence Stoskopf - 2015-05-25, 03:24

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