Sorry, but a load of rubbish!.
You can have voltage and no current, but you can't have current and no voltage - of course the voltage causes the current.
But you can't show scientific reasons to support your position.
You can have V w/ no I only under *static* conditions, i.e. a charged cap with a steady dc voltage. This is all V no I. But a lossless inductor is the counterpart of the cap scenario. A superconducting inductor has I w/ no V. Again, these are *static* conditions. Thus I exists w/o V, just as V exists w/o I. Of course caps have physical inductance, as inductors also have physical capacitance, but at dc, these have no influence.
In actual practice, there is no such thing as static. The cap could not acquire V unless I was inputted originally. The inductor could not acquire I w/o V. There is no such thing as "true dc" since all caps and inductors had to be energized initially.
Under *dynamic* or time-changing conditions, I cannot exist w/o V, and V cannot exist w/o I. In a cap, I leads V per Eli the ice man. Any change in V takes place AFTER a change in I. Thus the ac current cannot be "caused" by the ac voltage. The effect cannot precede the cause, as it is illogical. For an inductor, a change in current takes place after the voltage change. Thus I cannot cause V.
Two quantities, I & V, cannot exist alone, can only exist together, and depending on conditions, either can change before or after the other. This relationship is clearly not one of causality. In the static condition, either one can exist w/o the other. Clearly, neither can be the cause of the other.
The notion that "V causes I" is a common misconception easily obtained since all physical power sources are designed and optimized for constant voltage operation. The wall outlet has V but negligible I until you plug something into it. But the power company could just as well generate constant current. A short across the current source keeps the voltage at zero. Placing a load across and removing the short develops a voltage across the load. Here the current is always present, then a voltage develops when loaded.
V & I are mutually inclusive. Asking or stating which is the cause or effect is a chicken and egg viscous circle. They cannot exist separately.
MrAl
Of course MOSFET gates can need substantial current. I design power electronics as well as small signal circuitry. I use MOSFETs and IGBTs to convert power up to 800 volts, and 30 amps, with 10 hp motors. I even have rolled my own FET gate drivers that deliver substantial peak current to drive through the "Miller plateau" to switch the device as rapidly as possible. I know FET gate drives. The fact that FET gates need current is not under discussion. What the app note was referring to was under low frequency conditions. A FET used to switch on and off at a very slow rate needs very small gate drive. Using FETs in PWM mode in the 100's or even 10's of kHz requires high peak currents for the gate. But the AVERAGE gate current is MUCH LESS than the peak. A bjt, OTOH, needs high average base current even at dc or low frequencies. That is a marked difference.
Bill Beatty's site refutes all OEM semiconductor teachings. Bill claims to know more than Fairchild, Texas Instruments, On Semiconductor etc. That is quite a claim! His theory is filled with false assumptions, half truths, omissions, rush to judgment etc., and in fairness, some limited measure of truth. Bill and I exchanged emails a while ago. If you or anyone is interested, I could forward that email.
If Bill is right, the semi companies would have discovered what he claims a half century ago. They have billions in funds, research labs with state of the art equipment. Do you seriously believe that these PhD semiconductor physicists ALL got it wrong for over 50 years in many countries and companies? And, that Bill "discovered" what all of them couldn't grasp?
Get serious!
