[SOLVED] lm311 relaxation oscillator

[ymmen]

when we give -Vee = gnd, how can the ic work as relaxation oscillator i.e. when capacitor discharges it can never go below ground level voltage and hence inverting side stays higher than non inverting side giving 0V at output instead of square wave.

 

[D.A.(Tony)Stewart]

All relaxation oscillators work on charging up a cap with some hysteresis involved.

To use a comparator , with hysteresis the cap charging must be from negative feedback R and hysteresis from positive feedback ratio Rin_equiv/Rf ~ % Hyst. ., but must be biased near Vcc/2 as in datasheet Fig 44