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Unread 15-12-2015, 20:56
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Re: SD540 Motor Controller

Quote:
Originally Posted by Daniel_LaFleur View Post
Incorrect.

The output is 5VDC@1A not the input. The input is closer to 115VAC@0.05A or ~6Watts (assuming 1W inefficiency which is actually high).

In a phone charger (or most other chargers/USB power supply sources) you have a AC to DC converter (most likely a bridge rectifier). Then you have a buck converter (probably a transformer) and a switcher boost (High speed MosFET, inductor, and shottkey diode).


Exactly ,
Same is applicable for motor driven by these motor controller, input current and output current are not identical due to switching and stored energy in motor inductance. so you can not just calculate power dissipation in switch by looking at difference in output voltage and output voltage and output current
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