| ??? 02/11/08 18:23 Read: times |
#150609 - This is a real disappointment Responding to: ???'s previous message |
Erik Malund said:
What magnitude of noise and ripple have you observed with your switchers?
the magnitude of noise an ripple "I have observed" will, of course, be proportional to how much filtering I put on the board. So, how much did you observe, or, as is your usual practice, did you not attempt to observe anything at all? I routinely add a pi filter after the switcher and have absolutely no interest in knowing what the noise an ripple would be should I decide to save those $0.11 which I have no intention of doing.
How does Vcc behave after power is switched off? Just like any other form of regulation of course You stop supplying your filter capacitors, and your filter capacitors start discharging. This reaffirms my previous conclusion, namely, that you've not bothered to observe anything at all in your designs. Do you really just stick things in and hope they do what you expect? Erik With all the claims you've made about how things work, whether in RESET or Commm's, I'd have thought you'd have examined the your own work product at least superficially. However, it seems you've never, ever, looked at the Vcc of your designed product after it's assembled, just to see what the behavior of Vcc is. Don't your products have to meet specifications of any sort? Don't you wonder whether they meet those specifications? Do you have any idea what the power-gnd noise levels in your products are? Do you even care? The switchers I've used don't behave in the same way as linear supplies. The some of the linear regulators work differently, too. Apparently you haven't noticed that, yourself. I wonder why that is. RE All I was asking for was the numbers, ripple, random noise, Vcc rise time Vcc fall time, and maybe a comment or even a picture or two about how the supply and circuitry interact during the power-on and power-off transient. |



