Hello, I have a question regarding servo voltage.
I'm using a Raspberry pi to control servos. The negative and positive connector are connected to power source, and the signal line is connected to Raspberry Pi (through Adafruit 16 PWM servo hat actually).
It works fine with 5V and 6V servos.
But, if I were to use higher-voltaged servos, such as in the range of 7.4V -12V, can I connect the signal wire straight to Raspberry Pi?
Won't the voltage difference (5v from RPi, 12V from power source) damages the RPi?
Or the servos have one-way diodes in place to prevent current backflow?
Servo examples:
https://servodatabase.com/servo/tonegawa-seiko/ssps-105
Hitec HS
Thanks in advance for your opinions.
There are probably people who know better than me, but just to be sure maybe you should put the signal from the RPi through a transistor?
Just verifying that when you say servo, you mean the actual three wire servo with a power, ground and signal line yes? Not a two-wire motor that doesn't have any electronics in it, its just a motor (but sometimes people mistakenly call it "servo").
If it's an actual 3-wire servo, then yes you should be fine to just feed it in directly to the signal pin from the RPi GPIO. But for extra peace of mind, put a 10k resistor in series.
Yes. It's the 3 pin angular servo. Not the DC motor with 2 pin.
Glad to hear that. I'm really don't want to mess with step-up converters and such.
I guess I'll try to order one of this to see how it goes.
https://servodatabase.com/servo/hitec/hs-1000sgt
It can use 11 volt. I was afraid the 11v from LiPo would burn the RasPi GPIO pin from backflow or something, considering the GPIO is only 3V
Yeah as long as you keep your power domains separate and only feed the PWM signal (and keep common grounds) to the servo. You should be able to power the servo on whatever voltage you'd like.
Not sure how should I connect the servo/battery ground to the Pi though.
Should I just connect the servo ground (which is also connected to negative side of battery) to one of the GPIO ground pin? I suppose that would be safe?
Previously I used the Adafruit Hat power pin/lane which connected to external power, since my old servo is not too power consuming.
But according to documentation, we should hotwire the connection if there are too many Amps going through, since the hat lane is small.
So for this servo Ip just wanted to isolate the power line from the hat altogether. Hope the ground can be connected to the Pi directly. I suppose the Hat ground also can be used?
Now I've taken a closer look, the servois a 5-wire servo.
But it's not one of those 'dumb' old 5 wire servos that doesn't have electronics in it.
This one had extra red and black wire, in addition to the 3 'normal' wires.
I suppose we just connect those 2 extras to the same power supply anyway? Or is there a special way to connect them?
https://www.robotshop.com/media/catalog/product/cache/image/515x515/9df78eab33525d08d6e5fb8d27136e95/h/s/hs-1005sgt-heavy-duty-giant-scale-digital-servo-2.jpg
HS-1005SGT Heavy Duty Giant Scale Digital Servo - RobotShop
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