AHughes1984
New Member
Hell all new here.
I am designing a seven segment LED clock (yes a clock again lol) but am stuck with a MOSFET. What it is, is that am using an UDN2981 (high side driver array) and will be using PWM on the 6 CA seven segments using the PWM pin of the PIC16F877. I will be PWM'ing the VCC pin of the UDN2981 With a MOSFET (12V connected to the source and the drain connected to the VCC pin with the gate connected to a BC847 with a 1K resistor). My problem is that am not sure which type of MOSFET to use ie n-channel or p-channel. I think i should be going for the p-channel and use a BC847 on the MOSFET gate whit the BC847 connected to the PIC's PWM pin. So could anyone tell me if my thinking here would work providing i select the correct resistors to saturate the BC847 (to use as a switch).
All so is the current flow in MOSFETS bi-directional.
Hope i have gave you all enough info.
Regards,
AHughes1984.
I am designing a seven segment LED clock (yes a clock again lol) but am stuck with a MOSFET. What it is, is that am using an UDN2981 (high side driver array) and will be using PWM on the 6 CA seven segments using the PWM pin of the PIC16F877. I will be PWM'ing the VCC pin of the UDN2981 With a MOSFET (12V connected to the source and the drain connected to the VCC pin with the gate connected to a BC847 with a 1K resistor). My problem is that am not sure which type of MOSFET to use ie n-channel or p-channel. I think i should be going for the p-channel and use a BC847 on the MOSFET gate whit the BC847 connected to the PIC's PWM pin. So could anyone tell me if my thinking here would work providing i select the correct resistors to saturate the BC847 (to use as a switch).
All so is the current flow in MOSFETS bi-directional.
Hope i have gave you all enough info.
Regards,
AHughes1984.