- Published in issue 12/1993 on page 64
BASIC timer I
The time-determining element in the present circuit is capacitor C1, which is charged via a current source based on T1. The voltage across the capacitor is, therefore, a ramp. A comparison of this ramp with apreset voltage gives a fairly accurate time indication. With values shown in the present circuit, that time lies between 1 and 10 minutes.