The pulse-width stability of multivibrators-power supply effects

Those factors which influence the timing cycle of astable and monostable multivibrators are discussed in detail and a relation is derived which may be used to predict the sensitivity of frequency (or pulse width) to supply voltage changes. A compensating technique based upon the insertion of a compensating voltage into the multivibrator circuit is presented and discussed. Several compensating circuits are presented along with relations which may be used to estimate the compensating voltage required at a given operating point to reduce this sensitivity to zero. The efficacy of this compensating technique is illustrated by means of experimental results from several examples.