| 摘要 |
<p>The voltages (V1,V2,V3,V4) whose relative size is to be determined are applied to a resistance and capacitance connected in series and the times taken (T1,T2,T3,T4) for the potentials appearing across the capacitor to attain a threshold (Vth) are measured and their reciprocals determined. The reciprocals are linearly related to the potentials being measured and hence they measure their relative size. The measurements may be made using a standard low cost micro-controller which has a clock and counters of 16 bit precision even though the analogue to digital convertors which are not required for this purpose are only of 8 bit precision.</p> |
