Servos are weird: When my teensy 4.1 is connected to my 5v laptop, I can plug the positive terminal of the servo into the 5v pin and the servo should work fine (not recommended as voltage spikes when the servo moves), and 3.3v leads to janky movement (not sure if this is specifically with my servo or).
Another problem is that the Servo library does not support the ARM chip I have on my Teensy 4.1, which leads to compiler error. Any other library I can use with the teensy 4.1?
So my question is: if I plan on using a 7.4 lipo battery to power the teensy, can I also draw current and voltage from it for a servo? Would I need to add a voltage regulator to stop the servos from frying themselves? (Recommended voltage is 5v)
I'm making a PCB for the teensy which has servo connections, as has been done before. Can I connect the servo directly to the power 7.4v power supply? Or do I need a voltage reducer for that to step it down.. I don't have the option to use a separate supply as it would be too large for my usse case
Check the servo data sheet. Most are not rated for 7.4V.
If you use a stepdown converter, make certain that it can easily handle the servo start/stall current draw, times the total number of servos that will be attached and moving. Servos briefly draw the full start/stall current every time they start moving.
The general rule of thumb is 1 Ampere per small servo (SG90), 2.5 Amperes per large servo (MG996R).
The voltage regulator 7805 is regulated for 1.5 Amps as a max output amperage. If I want to power 2 SG90 off of this, would that be possible? Plus the regulator would be sending 5v to the teensy as well. By the logic you have provided, this should not work, and what could I do to work around this in my PCB?
According to the data sheet, the output current of the traditional LM7805 is 1 Ampere, maximum, which is not enough for two SG-90 servos and something else.
I would use a switching regulator, as they are much more efficient and would extend the battery life. Tiny, well designed switching regulator modules are available from Pololu.
Thanks for your help. I've opted to use a buck converter (voltage step-down module) LM2596. Seems to do the trick, and provides an excess of 3A (not continuous, but continuous amperage is around 2.2-2.5 amps).
