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Powering guidelines to CFAG240*?

gasparweb

New member
Hi!:

I just bought two GLCD from you. There are the CFAG240128L-YYH-TZ and CFAG240128L-STI-TZ. Im working on the interface with an LPC2148 ARM uC.

There are a few cuestions about powering and interfacing:

1. How connect Vo and Vee? Since this GLCD has internal inveter, wich circuit is requiered to dim the contrast?

2. Common values for trimmpot on 1.? Max Supply Current on Vo?

3. Pin 20 is called RV on datasheet? What it's does? Can be left unwired?

Thanks in advance and sorry for my english, im from Argentina.
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gasparweb

New member
one more

...continued...

4. There are any diferences in the power conections between the two LCD's?

Thanks!
 

CF Support2

Administrator
Hi!:
1. How connect Vo and Vee? Since this GLCD has internal inveter, wich circuit is requiered to dim the contrast?
You will want to connect your potentiometer across Vdd (pin 3) and Vee (pin 9) with the wiper going to Vo (pin 4) for your contrast control.

2. Common values for trimmpot on 1.? Max Supply Current on Vo?
We recommend using a 10K Ohm pot.

3. Pin 20 is called RV on datasheet? What it's does? Can be left unwired?
When we worked with the module, we tied RV to ground (low). We think it will invert the characters if you tie it high but did not verify that in our testing.

4. There are any diferences in the power conections between the two LCD's?
The only difference is the actual backlight LEDs with the "STI" variant being the brighter of the two which uses less current.

Thanks in advance and sorry for my english, im from Argentina.
You are most welcome -- and your English is fine and I can assure you is much better than my Spanish :)
 

Hans Chr

New member
About the RV pin:

Say I wanted to rotate the lcd module 180 degrees, will the lcd display data also be rotated 180 if the RV is connected to VDD?

Or is the data inverted (black to clear, and clear to black)?

regards

hc
 
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