about that LDO

May 24, 2012 23 Replies

My understanding of this circuit is qualitative, and a mathematical analysis would take far, far longer than there is justification or time for. The fet is in its ohmic region, so mathematical analysis would be terrible. But I did simulate it and tune the compensation to make sure that it behaves nicely over the range of expected loads. That is a bit safer than throwing in 100 pF and walking away. It wouldn't be stable with 100 pF.

John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators

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ys since you have a gate drive power supply a factor of 10x the output and = the main drive is a common drain and not a common source.

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gh performance marvels.

me of their transient response photos, and the 3083 is biased well away fro= m dropout in its tests. Both of those circuits make some attempt to close t= heir error loops out to the MHz regime, whereas your power source follower = swamps the output feedback with the integrating capacitor starting in low K= Hz.

performance marvels.

of their transient response photos, and the 3083 is biased well away from dropout in its tests. Both of those circuits make some attempt to close their error loops out to the MHz regime, whereas your power source follower swamps the output feedback with the integrating capacitor starting in low KHz.

VDS

performance marvels.

of their transient response photos, and the 3083 is biased well away from dropout in its tests. Both of those circuits make some attempt to close their error loops out to the MHz regime, whereas your power source follower swamps the output feedback with the integrating capacitor starting in low KHz.

VDS

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