I was trying to blink LEDs from a TS555IN today, and discovered the
> awful truth that its output stage stinks. =A0Somehow it's rated for 10mA
> source, 50mA sink (at 12V, 2V max. Vds(sat)). =A0The datasheet happens
> to overlook the fact that internal voltages change when the output is
> loaded. =A0Specifically, in astable mode, frequency drops and duty cycle
> drops. =A0When heavily loaded, oscillation stops altogether.
The output's buffered--that shouldn't happen.
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Are you taking feedback off the output pin? That would make it load sensitive. The original application circuits used the discharge pin instead.
-- Cheers, James Arthur