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... a basic 80Ma vibrating motor
[...] off a standard AAA power source
[...] IE : So it runs for 1 to 10 secounds, stops for maybe 5 secounds then repeats the cycle. I was told that a 555 timer could be incorporated with some type of either transistor or resistor on a small circuit board ?.
I didnt have a clue what they where on about, but I assumed someone here would know how to achieve this ??
I have 3 other projects that I can use the timer function in to alternate the running of some minature gear motors, as an on off swith is not an option. Need to be able to connect the power source when I wish to use the device and have it do its alternating thing for a few hours, then remove power source once finished.[...] The 555 timer may not be the best option however it is all I have heard about so far.
I am currently restricted to AAA for a power source due to size constraints within the component housing. And with this power source I can get in excess of 40Hrs constant run time which is more than ample for its purpose.
If I cannot have a timer due to the power limitations, than is it possible to have some type of electrical component that will allow constant current to the motor but in varying degrees of current. IE : current starts minimal then builds to maximum then cycles back to minimal again on a repeating cycle ?. This would still give me the varying degrees of vibration that I am after without overcomplicating the circuitry and cost of the device.
Alternatively I could use a 3v power supply if a resistor could be used to reduce the output to 1.5v, if 3v is enough to run the 555 timer ?.
This circuit should do, as Your motor requires 80mA and LM555CN can output 100mA.ONtime = 0.7 * R1 * C1OFFtime = 0.7 * R2 * C1*resistance in Ohms and capacitance in FaradsBy adjusting each pot You adjust time it takes for Your motor to be ON or OFF.As I have understood You require 0.15Hz frequency (10s ON, 5s OFF). I am not really sure how 555 timer will behave for such low frequency and how stable the performance will be.P.S. Also, could someone more experienced in circuit design review the diagram, please?
Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device performance.