I'm building a 48/12V generator circuit using the TPS61040 boost convertor using a doubler and switchable feedback resistance to select between the two output ranges.
The output is exhibiting a pronounced sawtooth wave in various operating modes -
I've been able to eliminate the ramping effect in the 48V mode by removing the output 10uF cap. But it's still very pronounced in the 12V mode. Loading the output with a resistive load only increases the frequency of the ramp, but it remains in the audio range even down to 1K (and the resistor is getting pretty warm!).
Does anyone know what the thresholds are for the ramping mode? Or have any other insights/recommendations into how to control this effect?
thanks much,
Brian
