I am working on a circuit to drive servos for a small bot I'm working on. I tried using darlingtons to build an h-bridge, but after several failed attempts and after branding a transistor shape on my finger while checking to see if it was hot I decided to use relays instead.
I have changed the reverse option from a 5v output of a microcontroller to a push button to voltage for simplicities sake.
What I am trying to figure out is the necessary resistance for the section of the circuits hooked up to the coils of the relays. Each relay has a 5vDC nominal range with 89.3mA nominal current.
There is also a voltage dropout of .25vDC
The Formula I am using is as follows
R1+R2+Rx=E/I
56+56+Rx=5/.00893
Rx=447.91
Here are my questions:
Based on this info I need a 447Ohm resistor to achieve the correct current?
Does the voltage dropout affect the equation?
Is there anything else I need to be aware of?
**broken link removed**
well I found the problem iwth this...... I made a mistake in my calculations.... shoutl be .089 not .0089
I have changed the reverse option from a 5v output of a microcontroller to a push button to voltage for simplicities sake.
What I am trying to figure out is the necessary resistance for the section of the circuits hooked up to the coils of the relays. Each relay has a 5vDC nominal range with 89.3mA nominal current.
There is also a voltage dropout of .25vDC
The Formula I am using is as follows
R1+R2+Rx=E/I
56+56+Rx=5/.00893
Rx=447.91
Here are my questions:
Based on this info I need a 447Ohm resistor to achieve the correct current?
Does the voltage dropout affect the equation?
Is there anything else I need to be aware of?
**broken link removed**
well I found the problem iwth this...... I made a mistake in my calculations.... shoutl be .089 not .0089