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Well I ran in to a problem, Got my stuff in the mail today and the heat sink they said would work for it is about size of my fist and about inch thick. Talking to them trying find one smaller but if there isn't one do you guys think It would be possible cut the sides of the heat sink off and just keep the middle of the heat sink that about inch thick? The threshold temperature for the LED is 150ºC and I got a Thermal imaging camera I could use to see how hot its getting.
Photo below is the Heat Sink they sent me
Photo below is the Heat Sink they sent me
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The data sheet certainly does show the dimensions. I looked at it and the OD is 2.75 inches. Since my circuit pulses the LED's with a very short duty cycle they will be running much cooler than with constant current. I know that there's a simple formula to calculate what your average power will be but my head is too clogged up with a head cold to figure it out.
Chris
Chris
I have an RGB 3-Watt LED on a star that has up to 2 colors at full brightness continuously on, (i.e. 2 Watts) and it gets hot to touch but not enough to burn you, with no heat sink. I am pretty certain you can get by with no heat sink at a duty cycle of even 50% and it will only be warm.
Bob
Bob
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Attach the LEDs to the heatsink while you're testing stuff. If it accidentally gets stuck ON at full power, this will make the difference between the LED getting far too hot (and possibly being damaged) and running at a normal temperature.
Once everything is operating normally, you can remove the heatsink and verify that the star itself is sufficient (you should be able to touch it, leave your finger on it indefinitely, and have it not feel hot -- warm is OK).
Once everything is operating normally, you can remove the heatsink and verify that the star itself is sufficient (you should be able to touch it, leave your finger on it indefinitely, and have it not feel hot -- warm is OK).
About time I got something right 
Im narrowing down to the finish and I need know If i got the following thing correct as well. I Know I got the Negative to Q1 mosfet/Drain and Positive wire from led to the 2w resistor then wire to 8 of 555 timer. But I need know if the wires hooked to the LEDs are right. Take look at the photo below
Im narrowing down to the finish and I need know If i got the following thing correct as well. I Know I got the Negative to Q1 mosfet/Drain and Positive wire from led to the 2w resistor then wire to 8 of 555 timer. But I need know if the wires hooked to the LEDs are right. Take look at the photo belowAttachments
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No, they're in parallel. Connect your +ve wire to the + lead of one of them. Then connect the -ve terminal of that one to the + terminal of the second. Connect the - terminal of the second to the drain of the mosfet.
It's kinda like batteries.
It's kinda like batteries.
So like this then? if not could you please show me in a drawing? Also capacitor C1 on the schematic the 1u the low leakage tantalum capacitor. They gave me one called TM1JP Dipped Tantalum capacitor 35v-1.0uf Is this capacitor right? link to the schematics https://www.electronicspoint.com/attachments/7098d1359757720-flashing-5watt-led-555hipwrledflshr.jpg
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You want this:
A picture is worth 1000 words. This is what I was trying to describe. My apologies if I was unclear.
On each star, the two connections labelled + are connected together, and are the two labelled -. Your wiring above would have resulted in an (accidental) short circuit.
Yes that capacitor sounds right. Make sure you know which lead is positive because tantalum capacitors don't like being connected the wrong way around.
A picture is worth 1000 words. This is what I was trying to describe. My apologies if I was unclear.
On each star, the two connections labelled + are connected together, and are the two labelled -. Your wiring above would have resulted in an (accidental) short circuit.
Yes that capacitor sounds right. Make sure you know which lead is positive because tantalum capacitors don't like being connected the wrong way around.
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ah dam think I short my circuit. I used a test LED with about same amount of volts/other stuff as the LEDs im using for this thing, to if it would flash be4 I put the real ones on it. The light wasn't flashing it was just on. Took it off when I seen that and when I did it again it wouldn't come on. Think I put c1 capacitor on wrong pin by mistake got take 2ed look at it. But It could been the other capacitor that goes beside it. It didn't have a Positive/Negative it looked like this http://www.westfloridacomponents.com/mm5/graphics/00000001/.0022uf-3000v.jpg
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If you want to test the circuit with standard LEDs you'll have to replace R3 with a higher resistance. Anything from 100 Ohms to 1KOhms will suffice for testing. The disk cap in your link would be the same type as used on pin 5, which is 0.01uF. This is not a critical value though. Anything up to 0.2uF will be practical.
Chris
EDIT: C2 is not a polarized cap. It can be connected in either direction. C1, which is the timing capacitor, must be connected with the positive (+) lead connected to pin 6.
Chris
EDIT: C2 is not a polarized cap. It can be connected in either direction. C1, which is the timing capacitor, must be connected with the positive (+) lead connected to pin 6.
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Just going tell you what I’ve done because I believe the problem is with the D1 Diode
Diode/D1
1:I have the anode side of the diode going to pin 7
2:The cathode of the diode to R5 the 10k resistor
3:R5 resistor goes to pin 6 with c1 positive
4:I have R2 1m resistor between R5 resistor and the anode of the diode
5:R1 1k resistor to anode of the diode to wire going pin 8
Ground for capacitor
6:I have a wire from pin 1 the (ground) going to the pin 5 area (not hooked to it)
7:I have C1 and C2 going to that ground wire
Q1 Mosfet
8: D going to negative of the LED’S
9:G with R4 10ohm resistor
10:I have another wire from pin 1 ground and it goes to the S The wire going to the grounds for the caps are only hooked together at the pin 1 ground but I don’t have the S and caps on same wires
Power
11:Wire from pin 8 going to R3 (5r/2w) resistor then to positive of the LEDs
12:The negative power for the LED Is the S of the Q1/Mosfet
Side thing:I forgot the switch in Pin 4 be4 I turned this thing so could that have been the whole problem of why the light wasn't flashing then not working at all?
Going fix that soon as I find a switch
Diode/D1
1:I have the anode side of the diode going to pin 7
2:The cathode of the diode to R5 the 10k resistor
3:R5 resistor goes to pin 6 with c1 positive
4:I have R2 1m resistor between R5 resistor and the anode of the diode
5:R1 1k resistor to anode of the diode to wire going pin 8
Ground for capacitor
6:I have a wire from pin 1 the (ground) going to the pin 5 area (not hooked to it)
7:I have C1 and C2 going to that ground wire
Q1 Mosfet
8: D going to negative of the LED’S
9:G with R4 10ohm resistor
10:I have another wire from pin 1 ground and it goes to the S The wire going to the grounds for the caps are only hooked together at the pin 1 ground but I don’t have the S and caps on same wires
Power
11:Wire from pin 8 going to R3 (5r/2w) resistor then to positive of the LEDs
12:The negative power for the LED Is the S of the Q1/Mosfet
Side thing:I forgot the switch in Pin 4 be4 I turned this thing so could that have been the whole problem of why the light wasn't flashing then not working at all?
Going fix that soon as I find a switch
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