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2016:extending_ir_range [2016/05/10 19:49] – created 75.177.137.22016:extending_ir_range [2016/05/10 19:50] (current) 75.177.137.2
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 Let’s start by taking a look at the TV-B-Gone schematic. Specifically v1.2: Let’s start by taking a look at the TV-B-Gone schematic. Specifically v1.2:
-{{:2016:tvbgone3sch.png?400|}}+{{:2016:tvbgone3sch.png?600|}}
  
 The schematic tells us that each IR-LED is driven by a companion 2N3904 NPN transistor. According to Adafruit’s datasheet on the Super-bright IR LEDs used in the kit, each LED has a forward voltage of 2.6V (max 4.0V) and a forward current of 1A max. You don’t need to current limit the LED’s with a resistor as each 2N3904 is only capable of switching up to 200mA and our supply voltage is <=3V. The schematic tells us that each IR-LED is driven by a companion 2N3904 NPN transistor. According to Adafruit’s datasheet on the Super-bright IR LEDs used in the kit, each LED has a forward voltage of 2.6V (max 4.0V) and a forward current of 1A max. You don’t need to current limit the LED’s with a resistor as each 2N3904 is only capable of switching up to 200mA and our supply voltage is <=3V.
2016/extending_ir_range.1462924167.txt.gz · Last modified: 2016/05/10 19:49 by 75.177.137.2