| 摘要 |
<p>A voltage controlled filter circuit with a voltage controlled resistor as a control element having a D.C. voltage applied to an ADC (analog to digital converter) compared to a supplied reference voltage, and as bits are set to HIGH or LOW level, then N Channel enhancement mode MOSFETs are turned on or off, bypassing the resistors in the ON state and placing the resistor in the current path when in the OFF state, providing control of the filter cutoff or critical frequency, critical frequency range being user selectable with external capacitor(s).</p> |
