It's a 12V motorcycle turn signal flasher. There are two capacitors and what I think is a variable resistor on the back side. Thanks a ton for the reply; I'm only in my second quarter taking prerequisites for electrical engineering so I know hardly anything about circuits. I'm trying to integrate a flasher circuit into a PCB that I'm designing using Easy EDA. Self learning what all the numbers and letters mean for each individual part is a little daunting but I'm slogging along. I suspect that I'll learn a ton from this forum, so I'm very grateful that you're taking the time to help me.hi Arien,
Welcome to AAC.
Which type of light did the flasher unit drive, eg: LED or tungsten etc.??
We need to know the details of the input/output voltages etc.
We maybe able to suggest an alternative MOSFET/BJT
E
I replied to Eric's question with some more details and photos. Thank you, suggestions for alternative parts would be very helpful. I'm trying to teach myself Easy EDA to design a pcb for a prototype I'm building. Alternative suggestions for the best way to have a circuit board made are also welcome. I am trying to teach myself AutoCAD Electrical, but it looks like easy EDA has a feature where I can draw a schematic, convert it to a PCB layout and have a printed circuit board sent to me in the mail. If it's not obvious, I'm in way over my head, designing the PCB is the last (and for me he most difficult) phase of my prototype.With some rash assumptions, it looks like the Source is connected to ground/com and the Drain (tab) is to load. That would be common for an N-channel mosfet. Like Eric said, if other factors allow you to estimate the current and voltage requirement, we might be able to suggest something that will work but with a different part number.
What I'm trying to design is a 12 volt LED turn signal flasher; I posted some more photos and details on Ericks comment above. I've been studying and drawing this schematic that I found online to try to wrap my head around how the circuit works. So far, I've learned a little about drawing schematics, but I'm too dense to understand what's happening to the electrons/holes moving through the circuit. I've been watching videos on how transistors and capacitors work. I think I understand the transistor labeled Q1, but I don't understand what's happening in the component labeled Q2. Am I correct in thinking it's some sort of mosfet? To be honest I don't yet understand the difference between a transistor and a mosfet. I also haven't yet wrapped my head around how this schematic relates to the photo of the circuit that I attached. I do know that I want to be able to vary the flash frequency, and I think they accomplished that using a variable resistor labeled 502 or 205 on the 12v motorcycle turn signal flasher that I attached a photo of. Tonight, after my math test that I'm supposed to be studying for, I will try to draw a schematic of the circuit board. (more photo's posted on Eric's comment)Post a schematic so we can see how the MOSFET is being used (required threshold voltage and current capacity).
Yes, Q2 is an N-channel MOSFET. It's being used here as a switch, like a relay. That is, it's either on or off. R1 pulls the gate low to turn it off when Q1 is not conducting. When Q1 conducts, the gate voltage rises above the source voltage, and the MOSFET turns on, completing the circuit for the lamp.... I don't understand what's happening in the component labeled Q2. Am I correct in thinking it's some sort of mosfet? To be honest I don't yet understand the difference between a transistor and a mosfet.
You are awesome! Is Q1 a PNP transistor, and M1 a n channel mosfet? I'm studying how those two components work to try to understand the current flow.hi Arien,
This is the circuit in LTSpice simulation.
Looks OK to me.
E
Update:
Increasing R3 increases Lamp ON time
Increasing R2 decreases flash rate.
View attachment 198898
I think so. Would that be an N-CHANNEL ENHANCEMENT MODE POWER MOSFET? https://datasheetspdf.com/pdf/1257114/AdvancedPowerElectronics/AP60L02H/1Might it be a 60L02H MOSFET?