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Transistor and resistors

MichelBMichelB Posts: 154
edited 2009-07-01 14:48 in Accessories
In chapter 6 of Applied Sensors, Figure 6-2 which are the functions of R 100 ohm and R 10 ohm 1 watt between transistor and pump? According to this activity pump needs 300 mA at 3 VDC?

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2009-07-01 14:08
    The 100 Ohm base resistor (as well as the 10 Ohm resistor and the motor resistance) limits the base current from the Stamp to something less than 25mA. More could damage the Stamp I/O pin.

    The 10 Ohm resistor limits the current through the motor since the motor is designed for use with a 3V supply and the motor circuit is powered from the 5V regulated supply.
  • MichelBMichelB Posts: 154
    edited 2009-07-01 14:48
    Thank you Mike, you are very good at all.
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