Hi,
I am working on a project where all the sensors and the microcontroller (PIC18F4550 ) are powered from a 3.3v source.
I want to introduce a GLCD to the project. The problem is that GLCD logic high input must be at least 2V, which is just above the logic high output of the PIC, so I cannot connect the GLCD directly to the PIC.
I bought some 2N7000 n-channel MOSFET transistors to use them as switches, as shown in the image. I connected such switches to all the pins required between the PIC and the GLCD (14 pins). The value of R1 I used in all the switches is 1Ω.
I ran a sample program to test the GLCD, but it did not work and the transistors became very hot after a while. I checked for short circuit, but couldn't find any.
What do you guys think the problem is ? Is the resistor value too small? if so, what value should I use ?
Thanks a lot.
I am working on a project where all the sensors and the microcontroller (PIC18F4550 ) are powered from a 3.3v source.
I want to introduce a GLCD to the project. The problem is that GLCD logic high input must be at least 2V, which is just above the logic high output of the PIC, so I cannot connect the GLCD directly to the PIC.
I bought some 2N7000 n-channel MOSFET transistors to use them as switches, as shown in the image. I connected such switches to all the pins required between the PIC and the GLCD (14 pins). The value of R1 I used in all the switches is 1Ω.
I ran a sample program to test the GLCD, but it did not work and the transistors became very hot after a while. I checked for short circuit, but couldn't find any.
What do you guys think the problem is ? Is the resistor value too small? if so, what value should I use ?
Thanks a lot.
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