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LED Current Limiting Resistor Calculator
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Parameters
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Maximum LED Forward
Current
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mA
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Typical LED Forward
Voltage Drop
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V
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Supply Voltage
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V
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Number of LED's in Series
(Chain)
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Number of Chains in
Parallel
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Results
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Total Current Drawn
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mA
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Voltage Across Resistor
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V
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Resistor Value
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Ohms
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Power Disapated in
Resistor
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W
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How to use LED Resistor Size Calculator
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1. From
the LED data sheet, identify the maximum LED current
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(IF) or enter a lower
value if desired
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2.
From the LED data sheet, identify the typical forward voltage
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(VF) and enter this value
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3. How many LED's do you
have connected in series, enter this
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number, minimum 1
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4. How many
chains of LED's do you have connected in
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parallel, enter this
number, minimum 1
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5. Under results, the
first two values are for info only. The third
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value is
the resistor value, you would normally choose the
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nearest preferred value
above this number.
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6. The last result
indicates the power dissipated in the resistor,
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you need to make sure
that the resistor chosen has a power
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rating above this figure.
Standard resistors are typically 0.25, 0.5
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or 0.6W but power
resistors above this are available such as 1W,
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2W,etc..
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Disclaimer:
Whilst we have taken evey care to ensure this calculator gives the correct
answer, Technobots cannot be held responsible for any errors and their
consequencies.
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