| 摘要 |
<p>A heavy-load driving device for a electronic watch is provided that assures reliable timekeeping operation and enables proper drive in accordance with the power supply voltage level. When drive command circuit generates an alarm-coincidence signal Sa, this signal Sa causes a preparatory judging circuit 10 to operate, so as to make a judgment, in accordance with the reduced power supply voltage level under a given load condition, as to whether or not to allow drive of a beeper device 31, a drive-enabling signal Svm being output if the judgment is to allow drive. By doing this, a heavy-load voltage detection circuit 21 starts to output a drive-time judgment signal Pvh which indicates the power supply voltage level judgment results. By means of the Svm signal, the a drive-signal control circuit 23 begins to operate, and at a drive condition selection circuit 25, in accordance with the signal Pvh, successive selection is made of a drive signal to be supplied to the beeper device 31 from the plurality of drive signals B75, B50, and B25 which are generated by the a drive-signal generating circuit 16, the selected drive signal driving the beeper device 31. <IMAGE></p> |
