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The 2 motors draw 2,8 A each and have a stall current of 6A.
I have 2 LM350T switching regulators at my disposition. Can i use a normal 12V regulator (as my battery is 12V), and for the 12=>5 the LM350T switching one?
Powering the motors is essential because my other circuits are allready regulated.
What other circuits?
Yes, you can connect the battery directly to the motor driver. Make sure, of course, that the motor driver is capable of handling the voltage and amperage your motors require. Also the schematic you posted would be used if you wanted to power the rest of your circuitry off the same 12v power source. The purpose of the inductor in the circuit, as Admin pointed out, is a noise filter. It is there to regulate the current to the voltage regulator and, as you know, inductors oppose changes in current. If your load (the motors in this case) draws excessive current (like when the motors stall) the inductor helps to maintain a constant current to the regulator.If you don't need a battery monitoring circuit, K1, R1 and R2 can be eliminated. For the LEDs and associated resistors, you can use this LED calculator to calculate appropriate resistors for your circuit.Maybe someone with more of an engineering background can give you a better guide on capacitor selection, but these are some general things to keep in mind. The capacitor needs to be rated for a voltage higher than the peak voltage expected, typically 1.5 x peak voltage. If you expect a peak voltage of 15v off your 12v battery, you would need a capacitor rated for about 23v for C1. The purpose of the capacitors in this circuit is to filter changes in voltage. In general a larger capacitance is better able to filter low frequencies, while a smaller capacitance is better at filtering higher frequency noise. The 220 and 470 µF capacitance values should be appropriate for a 12v power supply as well.Lastly, I would recommend the DE 5v switching regulator. While the LM350 can be used, it would require additional circuitry (see the datasheet) and wouldn't be a drop in replacement.
Well my motor driver's H-bridge is the LMD18200T, one for each mother and each capable of a 3A continuous output. So I guess they will do the job.
I'm going to try those LMD18200T and see if they'll do, i'm not planning on pushing him that hard.
It's not for a racing competition or time critical application so the motor's won't be driven to the max. I'll adapt to 5A bridges if i see they still draw to much current. Any ideas on what type of solid state h-bridge i could use? Are their dual bridge drivers out there. So 2 h-bridges in one package?
Assuming he is going to 'mother' over his robot like most of us do, all he needs to do is touch to see how warm it gets, no current sense needed.
Current spikes when you first start running the motors, so you can't just shut the motors off when current gets too high.