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HoangTran83
11-08-2010, 06:31 PM
Is there a direct way to measure the power consumption of the propeller using a multimeter?? (measuring the amount of current the propeller draw?) I want to be able to measure the power consumption when one cog is active and also when multiple cogs are active. Will the temperature of the propeller chip be higher when multiple cogs are active vs one cog active?? any advice is greatly appreciated. Thanks

Hoang

markaeric
11-08-2010, 06:37 PM
Most multimeters should have a mode that let you measure current in series with a power supply.

Heat is a byproduct of power. It should be safe to assume that the more cogs that are running, the more current that is being used, and therefore, more heat that is being generated.

HoangTran83
11-08-2010, 06:44 PM
Will the temperature change of one cog running VS all cogs running be noticeable (measurable?).

pgbpsu
11-08-2010, 06:46 PM
A good source for this info is the propeller datasheet. It will give you an idea of what to expect in your design. Although these measurements were made in a lab. Your measurements may be different but this should give you a reference.

http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/PropellerDatasheet-v1.2.pdf

Phil Pilgrim (PhiPi)
11-08-2010, 07:16 PM
If you have a Propeller Demo Board, there's a handy jumper (labeled IVdd) that you can remove to fasten your milliammeter leads to. This allows an easy reading of current consumption on the 3.3V bus without having to make any weird adapters or having to account for the regulators' quiescent currents.

-Phil