| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a key press detecting circuit for detecting the status of a key. <P>SOLUTION: The key press detecting circuit comprises: a discharging circuit which discharges when the key (K1) is pressed; and a voltage detecting circuit, which comprises a combination of a PNP transistor (T2) and an NPN transistor (T3), wherein when the discharging circuit discharges for a predefined period, the PNP transistor (T2) will be turn on, which causes the NPN transistor (T3) to be turned on and to output a second signal for a second function. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
