1. First u need to choose the mosfet type whether n-channel and p-channel??
2. Voltage rating (Drain to source)
3. Current rating (Drain current)
4. Switching time
I am designing a driver circuit for LED-power supply(60-200V) and my block diagrams are as follows.Here we have to give instantaneous voltage,current(Hall effect sensor output is a low voltage signal represents the instantaneous current) and reference values as inputs to the micro controller and output what i need is the gate pulses to mosfet . **broken link removed****broken link removed**
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pls say the details regarding the LED-driver you know.In my circuit i am going to monitor instantaneous voltage,current and they are inputs to the micro controller,so we control instantaneous power according to our will
From my side what i am thinking is the pic micro controller has many ports which are unnecessary for me and we have to study a lot to know more about pic operation.So please suggest the micro controller which is low cost and easy to operate
for small projects we find the PIC24 microcontrollers with Peripheral pin Select functionality very useful. PPS enables one to use a small pin out device (e.g. a 28 pin SDIP) and then map required peripherals at run time giveing flexibility and simplifing PCB layout. For example, the PIC24HJ64GP502 PIC24HJ64GP502
the PIC24HJ64GP502 is used with Microchip's microstick
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which is useful for small projects, e.g. low cost, on board programmer, header for connection to a breadboard, etc
in practice it is not just a question of the cost of the microcontroller (e.g. the 16f676 is about $1 and the PIC24HJ64GP502 is about $3 for one off) but the overall project, e.g. other support chips required, development time, PCB layout costs, long term viability, etc. Even when working on projects producing 10000 units a year one has to look further than microcontroller cost!
The guy needs around 2 I/O pins. Why does he need a 16, bit micro? What are all the 'support chips' he will need if he uses a smaller micro? Is it easier to lay out a PCB with a PIC24 than a PIC16? I don't think so. 'long term viability'? What is that supposed to mean in the context of microcontroller choice from one manufacturer? I would have thought one of the PIC10 or PIC12 chips would do the job but for a high volume product which really needs low cost then you need to look at something other than PIC. Holtek have some cheap processor I believe.
I think you are beginner to microcontroller...SO the better choice is to choose the 8051 only....its basic level of controller...Use AT89c51 or AT89c55WD...
it depends on which country you are living
in india the cheapest controller available(according to my knowledge) is AT 89c2051/1051.
i heard there are much cheaper controllers available in china/thaiwan but is not available in india.
if you need to save space ie.you need only two pins use PIC 10F/12F or ATTINY series.
keith1200rs is right , all you need is something like PIC12F509. More than that , the only input you need is a zero cross detector , the voltage is known as U*sin(ωt). Since C and R have no value in your schematic I cannot calculate the current but I see a big problem with it. My guess is that you will command the Mosfet in switched mode ON and OFF and there is no resistor in the current loop , when you switch the Mosfet on the only limitation for current is the saturation current of the Mosfet since R is bypassed by C witch can damage your LED's.
If this is just a starting point leave the capacitor and use a value for R that at maximum voltage 230*√2 will result the maximum current supported by the LED's in pulses.
mdorian i hav one doubt,capacitor limiting the current before itself so there is no damage for LED's,but u said leave capacitor y??and what is the need of zero crossing detector.Pls explain for me
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as a beginner i planned to use 8051 micro controller but now i am planing to use PIC12.Is there any advantages for going PIC12 instead of 8051 for my application?