Johnson & Johnson
Extended period timer circuits for ophthalmic devices

Abstract:

Programmable timer circuits are disclosed. One timer circuit may include a reference circuit configured to generate a bias current, a current controlled oscillator configured to receive the bias current c, and a frequency divider network configured to divide an output of the oscillator. The timer circuit may be capable of timing for 24 hour period, while using less than 5nA of quiescent current.