pin assignments on 4x40 LCD (CFAH4004A-YYB-JP)


New member

I just had a question on the pin assignments of the CrystalFontz 4x40 LCD. What is the purpose of pin 13 (V0) and pin 16 (NC/Vee)? Also, if i want to control the contrast of the LCD display, which one of these pins would i use?

Any help is appreciated.

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CF Tech

For a CFAH4004A-YYB-JP:

Pin 16 is NC (no connect)

Pin 13 is Vss (ground)

Pin 12 is Vo ("contrast")

Set pin 12, Vo to about 1v for starters, then adjust it for optimal viewing. Typically you would conenct a 10K pot between Pin 13 (Vss or ground) and Pin 14 (Vdd or +5v), with the wiper connected to Pin 12 (Vo).