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Topic: Which Diode to use to protect a Servo (Read 1 time) previous topic - next topic

Ben1234

I am running 4x Continuous Rotation Servos https://www.sparkfun.com/products/9347? at 6v (not sure about amps as it is not given in any datasheet that I can find, if you know it would be greatly appreciated). More importantly, I have read that Schottky Diodes have a smaller voltage drop, so I was wondering what the pro vs cons of using those or 1N4148 diodes to protect my servos from accidentally reversing the voltage and frying them. Is one more appropriate than the other to use for this application, as if the voltage drop is the only factor then it seems like I should always use the Schottky Diodes? Thanks in advance for your help.

Ben1234

To add the power source for the servos is 9v

MarkT

A 1N4148 cannot take the current levels of a typical servo, limited to 0.2A.  A schottky diode rated at say 4A+ continuous would be a better match for this role,
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

retrolefty


To add the power source for the servos is 9v


9 vdc can very easily damage a servo as most are rated to run at 4.8 to 6.0vdc. So you need to do something about that before dealing with reverse polarity protection.

As far as current draw for servos, most manufactures don't give much useful information as the amount varies so much with the mechanical load one might have with each different installation and application of the servo. The current is mostly a function of what the motor draws and that is related to the load on the servo. A servo at standstill with no torque load may only draw 20ma of current but can quickly draw over a 1 amp or more when turning against a load.

Lefty

Ben1234

Sorry, I forgot to mention that I have a 5v regulator between the 9v power source and the servos so really they will run at 5v, not 6v

Ben1234

If I had one of these for each servo https://www.sparkfun.com/products/10926 would this be an optimal/acceptable solution?

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