Re: Need help intepreting datasheet -- how much current does this IC use?
The topic of this thread has to do with two questions asked by Nathan: (1) how much current does this IC use? and, (2) Is that [20 uA] the amount of current it uses while operating? In both cases, I read his questions to be about the power supply current drawn by the IC while operating in an application circuit. I could not find the answer to his questions in the data sheet or other literature associated with it. I did not find the answers to his questions in your message. I answered his second question with, "No". I'm not willing to answer your question, "what's not to like about the spec?" within this thread because it seems to me that to do so would lead us too far away from the topic of this thread and I'm still working on Nathan's first question and related questions like, "What is a logical definition of the power supply current drawn by an IC operating in an application circuit?" and, "How might one measure the power supply current drawn by an IC operating in an application circuit?"
I have figured out how to define the power supply current for a quiescent IC in an application circuit.
I'm out of time for now. Maybe I will have more later.
--- In Electronics_101@yahoogroups.com, Donald H Locker <dhlocker@...> wrote:
> I thought it perfectly adequate - Icc is the maximum current the chip draws under the specified conditions... - what's not to like about the spec?
> > --- In Electronics_101@yahoogroups.com, "nathan_h_tna"
> > <nathan_h_tna@> wrote:
> > >
> > > I'm a student and, unfortunately, am not very good at interpreting
> > datasheets. I'm trying to figure out how much current a SN74HC12N hex
> > schmitt inverter uses.
> > >
> > > Here's the datasheet: http://www.ti.com/lit/gpn/sn74hc14
> > >
> > > Under "electrical characteristics" it says ICC = 20 uA. Is that the
> > amount of current it uses while operating?
> > >
> > > Thanks for your help!
> > >
- --- In Electronics_101@yahoogroups.com, Derek Koonce <derek@...> wrote:
>Why not just set up whatever is considered by the OP to be 'quiescent' and measure the current? Add output load, don't add output load, whatever. Just measure...
> Give them both a call - phone even. Both companies are very helpful. If
> not, send me a private reply and I'll find you someone to talk to. Why
> bother doing what could easily be found by asking. CMOS circuits are
> very low power. Since MOSFET impedance is in the 10's of megaohms, and
> these circuits are usually designed with high-value resistors for
> internal gate driving, static current consumption is very low as the
> data sheet states. If you are looking for exact values, no one can
> provide since lot-to-lot variances are involved; thus maximum values are
> usually given.
> Time is money in my case and you seem to have worked too long on this
> question. Stop beating a dead horse. ;-)
> Derek Koonce
> DDK Interactive Consulting Services