neil2501_h8
New member
Hi,
It is my first time to design a EL backlighting circuit to drive CFAG12864BWGHV module.
I have searched the net and found Supertex HV8XX IC series that should do the job. I choose HV830 in particular because it provides it seems to provide one of the highest Vpp (typ. 200Vpp) among the other HV8XX series. Referring to the specs of LCD module, the typical Vrms required is 110V.
The basic conversion between Vpp & Vrms is given below:
() Vrms = Vpp / Sqrt(8)
() Vpp = Vrms * Sqrt(8)
Then Vpp(required) = 110Vrms * Sqrt(8) = 311Vpp
From the above calculation, it means the HV830 IC is only capable of providing 70% of the typical Vrms required for LCD module! Will this be a problem for the EL brightness?
In my design, I use a 2M ohm resistor connected to pin 8 of HV830 to give an output wave of 400Hz. Will frequency of the output wave affects the color of EL backlight?
Please advise if the circuit incorporating HV830 can be further optimised or it has to be replaced with another circuit. I can only find Supertex ICs available for sales online (@ www.mouser.com) that provides EL backlight driving features.
Many Thanks in Advance!
It is my first time to design a EL backlighting circuit to drive CFAG12864BWGHV module.
I have searched the net and found Supertex HV8XX IC series that should do the job. I choose HV830 in particular because it provides it seems to provide one of the highest Vpp (typ. 200Vpp) among the other HV8XX series. Referring to the specs of LCD module, the typical Vrms required is 110V.
The basic conversion between Vpp & Vrms is given below:
() Vrms = Vpp / Sqrt(8)
() Vpp = Vrms * Sqrt(8)
Then Vpp(required) = 110Vrms * Sqrt(8) = 311Vpp
From the above calculation, it means the HV830 IC is only capable of providing 70% of the typical Vrms required for LCD module! Will this be a problem for the EL brightness?
In my design, I use a 2M ohm resistor connected to pin 8 of HV830 to give an output wave of 400Hz. Will frequency of the output wave affects the color of EL backlight?
Please advise if the circuit incorporating HV830 can be further optimised or it has to be replaced with another circuit. I can only find Supertex ICs available for sales online (@ www.mouser.com) that provides EL backlight driving features.
Many Thanks in Advance!
Looking for additional LCD resources? Check out our LCD blog for the latest developments in LCD technology.
Attachments

504.1 KB Views: 261