I have a project in which we are given a supply of DC voltage and current (which can be tweaked if necessary). From this supply, I need to drive 4 DC motors and a few other electronics which each require their own level of voltage and current signals.

My first question is, Can I connect the DC motors to the supply line directly and they will share the current equally? Is a trimming resistor necessary for each motor, and how do I go about determining what resistance value is needed? If I use a PWM scheme with an H-bridge to control motor speed, can I send one signal to all four motors or does each motor require its own control?

My second question is, Can I use some kind of single-input, multiple-output DC-DC converter to power the electronics? For example, one device may require something like 3.3V and 45mA, another 5V and 1.2A, and another 12V 500mA. If I have to build a DC-DC converter, will I have to use a battery to generate the switching signal for the DC-DC converter?

I don't have any work to show because I haven't started yet and don't fully understand the project yet. Am I going about this the right way? Also have zero experience with motor control. Thanks all.

 

If dc power supply is powerful enough, I would just use multiple voltage regulators. For 5 VDC LM7805 is very common.
https://en.wikipedia.org/wiki/78xx

 

It would help if you knew (and could share) the voltage and current requirements of each component.

 

The electronics components are:
3.3V and 45mA
5V and 1.2A
12V at 500mA
The 5 motors are rated at 24V and 0.5 horsepower which I converted to 372.85 W which is 15.5A each.