Hi,
I've found a 20x4 LCD screen, the PC2004A by Powertip, their datasheet is quite rubbish really although from what I gather it is the equivalent of the HD44780 controller (Edit: No, the actual controller used is a ST7066U, a completely different animal), but I'm having a couple of issues understanding the powertip datasheet:
http://www.farnell.com/datasheets/355527.pdf
I understand the "Pin Assignments", but get a little confused when it comes to the "Absolute Maximum Ratings" and the "Electrical Characteristics" sections.
1) When they say "Vdd-Vss", are they meaning the voltage of Vdd (+ve supply) in relation to Vss (GND)?
2) They then mention the LCD driving supply voltage as being "Vdd-Vee", but I can't see a Vee pin at all? Although it seems that Vee means GND also, but why did they use Vee rather than Vss?
3) There doesn't seem to be a Vin pin at all listed in the "Pin Assignments" despite being mentioned as the "Input Voltage".
4) Under the electrical characteristics the "LCD Operation Voltage" uses the symbol Vop, again there isn't a Vop symbol, should the Vo symbol in the "Pin Assignments" actually be Vop?
5) What do the N W symbols mean?
6) The sheet keeps mentioning -0.3V as a minimum, how exactly could things work with such a low negative voltage?
Thank you,
Gump.
I've found a 20x4 LCD screen, the PC2004A by Powertip, their datasheet is quite rubbish really although from what I gather it is the equivalent of the HD44780 controller (Edit: No, the actual controller used is a ST7066U, a completely different animal), but I'm having a couple of issues understanding the powertip datasheet:
http://www.farnell.com/datasheets/355527.pdf
I understand the "Pin Assignments", but get a little confused when it comes to the "Absolute Maximum Ratings" and the "Electrical Characteristics" sections.
1) When they say "Vdd-Vss", are they meaning the voltage of Vdd (+ve supply) in relation to Vss (GND)?
2) They then mention the LCD driving supply voltage as being "Vdd-Vee", but I can't see a Vee pin at all? Although it seems that Vee means GND also, but why did they use Vee rather than Vss?
3) There doesn't seem to be a Vin pin at all listed in the "Pin Assignments" despite being mentioned as the "Input Voltage".
4) Under the electrical characteristics the "LCD Operation Voltage" uses the symbol Vop, again there isn't a Vop symbol, should the Vo symbol in the "Pin Assignments" actually be Vop?
5) What do the N W symbols mean?
6) The sheet keeps mentioning -0.3V as a minimum, how exactly could things work with such a low negative voltage?
Thank you,
Gump.
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