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Totem pole output what is
Totem pole output what is












Powering the switching IC is not such a problem, as the top of C4 – the Cuk capacitor, is at a relatively stable dc voltage relative to local-IC-0V, and so a three-terminal regulator (LDO or dc-dc) could easily do that, maybe with a diode to prevent the regulators input capacitor from messing with the Cuk capacitor, or Cuk capacitors triangle wave from pushing through the regulator.

totem pole output what is

However, the traditional T元41+optocoupler feedback used in isolated ac-dc power supplied could easily cross this, I claim…. The graph right shows the horrendous waveform across which feedback signals would have to jump – the local IC 0V is a -34V 333kHz square wave relative to the output’s 0V. There is a huge drawback with this scheme, as neither the input+output 0V (triangle symbol in circuit diag), nor the negative output, have a dc connection to the IC’s local 0V. LTspice note: I had to delay the start of the input ramp to avoid giving the simulation tool a headache. And if LTspice has done its work well, it looks like this technique would indeed work as the output (lower line on graph left) settles to -2x the input voltage in this converter, whose input fet (top fet in diagram above) has a 2:1 on-off ratio.














Totem pole output what is