We decided to use the TLC5957 LED driver of Texas Instruments with Broadcom RGB LEDs: ASMB-KTF0-0A306.
First, we have to determine the maximum current which will be used. The 3 colours of the RGB LEDs can get a 20 mA input current max and the driver can handle 20mA sink current max. So we choose a maximum current of 20mA.
We decided to configure the driver with the maximum value for the Brightness Control (BC) (and by consequence, the maximum gain) to provide the intensity to go over 20mA. So we have to choose a value of BC equals to 7.… Read more
We need to be able to drive our little magnet marbles and flip them according to a magnetic field direction or the opposite one. To do so current must be able to flow both ways through our self-inductances. Moreover we’re going to need current’s intensity of a much higher value than what is able to flow out of or flow in the GPIO.
One way to do so, is to use a H-Bridge as we can see on this site that we’ve already mentionned in an earlier post.
What’s an H-Bridge
Basically an H-Bridge is a electronic circuit built with drivable switches in a way that allows us to flip the voltage on a load and thus allows us to flip current polarity.… Read more