powering a picaxe
February 25, 2010
Hello all LMR,
Calculon continues to work on his XMOS challenge, but has once again come across a snag.
The SNAG: He is trying to power his picaxe with a 5v out from a motor controller. It doesn't work.
The controller, a pololu Qik 2s12v10, is connected to a 12v. When measured with a multimeter, the motor controller shows 4.9 volts, 49 ma coming out to the picaxe. The breadboard indicator LED lights up. But the picaxe, she does nothing. When connected to 4 AAs, the voltage and current draw is the same. The only difference: with the 4 AAs, the picaxe works, but the LED is significantly dimmer, despite the similar current draw and voltage.
If both the controller and the 4 AAs are connected to the board, the picaxe works. For the life of him, Calculon does not understand the difference.
From the Qik user guide:
This line connects to the 5 V output of the qik’s voltage regulator and can be used to power additional electronics in
your system. It can safely supply up to 70 mA beyond what the board draws when VIN is 16 V. The closer the input
voltage is to 5 V, the more current the regulator can deliver without overheating.
Also, do not ask why a picaxe is important for the XMOS challenge. Calculon will not answer.