Need advice on arduino controlled 1w chip led array

Using Arduino Project Guidance
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Im looking to make a light array with 1w chips but i need to be able to pulse the light on and off rapidly. I want to flash the leds from 1hz to 60hz while being able the PWM dim them. I achieved this with 5mm leds but now want to use 1w chips.

I'm trying to figure out if the best way to do this is to use transistors or mofsets to do this

If anyone was as any input or parts in mind it would be appreciated.
Thanks

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1Hz to 60Hz is jiust software, see blink without delay.
PWM is a PWM output driving a Logic Level, Low Rds, Low Gate Capacitance N-channel MOSFET to connect LEDs to Gnd.

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You can use simple transistors or MOSFETs. But, make sure to calculate the power dissipation in the current limiting resistors and use large-enough resistors to handle the power (and heat).

How big is the array going to be?

When you get to around 1W (or more), the standard approach is to use a special controlled-current switching supply instead of a current limiting resistor ([u]examples[/u]). You can build one, but it's not the easiest thing to build. You would need one supply for each LED, or at least for each row & column in your array, but doubt the standard supplies can be used to control rows/columns. You'd need to get a dimmable supply, and you'd still need a small transistor because these things usually need a 10V control signal.

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the array is most likely going to be from 10 to 15 1w LEDs.

I was wondering about single constant current driver like this http://www.ebay.com/itm/370632520478?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 but I was afraid the driver would not turn on and off instantly. My past experience with a constant current driver the LEDs would take a split sec to turn on then fade off.

How I did it with the 5mm LEDs was a pin was set high at 1 -60hz to the anode and a pin was used to the cathode with PWM for dimming (the circuit was resistor current limited of course).

Thanks

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easterly81:
I was wondering about single constant current driver like this http://www.ebay.com/itm/370632520478?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 but I was afraid the driver would not turn on and off instantly. My past experience with a constant current driver the LEDs would take a split sec to turn on then fade off.

That particular driver will turn on/off instantly. It has a "dim" input that would be used for that.

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So the driver remain on I'm just going to control the blink frequency with the dim input ie if I want the LED at 100% brightness for 1hz set the dim input at 100% for .5 sec then .5 sec at 0% Or if i want it at 50% brightness set it at 50% for .5sec then 0% for .5sec, ect.

or go this route? http://www.ebay.com/itm/16-channel-12-Bit-PWM-I2C-FET-Arduino-schield-PCA9685-/370899927156?pt=LH_DefaultDomain_0&hash=item565b5bc074

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