That's true for a constant output voltage. But if the power supply is in the current limit (constant current) mode then it simply adjusts the output voltage to maintain the selected current. Thus the resistance of the load has no effect on the current since, if the load resistance changes, so does the power supply output voltage thus maintaining the same output current.How is it that you can simply turn the current delivered to your circuit up or down on a bench DC power supply?
As of right now I think that it's the resistance of the load that determines the draw. What am I missing?
You are missing the idea that a power supply can be used as a constant voltage supply or a constant current supply. It's either a constant voltage with the capability to deliver up to a certain amount of current or a constant current supply that is capable of delivering up to a certain maximum voltage limit. Each of these has their advantages and weaknesses. It's up to you to pick which one will do the job best at this moment.How is it that you can simply turn the current delivered to your circuit up or down on a bench DC power supply?
What am I missing?
Bench supplies can operate in either constant voltage or constant current mode. There are two different control loops inside the PS.How is it that you can simply turn the current delivered to your circuit up or down on a bench DC power supply?
As of right now I think that it's the resistance of the load that determines the draw. What am I missing?
Don't know why you say that. You can control current to the same degree that you can control voltage. Both are bounded by the voltage and current limits of the power supply. Stay within those limits and you can have full control of either the current or the voltage, as desired (assuming the power supply has both current and voltage control circuits such as shown by Stuntman).Current can only be limited and not controlled It is done by varying the voltage.