| 摘要 |
PURPOSE:To enable to obtain stable ignition in a wide temperature range, by constituting a DC bias circuit by connecting a diode and a resistor having a high positive temperature coefficient in series to each other, and connecting an electromagnetic pickup coil at the junction of said resistance and the diode. CONSTITUTION:One end of pickup coil 1 is biased by a DC bias circuit which consists of Zener diode 2, resistance (diffused resistance or the like in IC) 3 having a high positive temperature position temperature coefficient, resistances 4, 5 and diode 6. Output of the coil 1 is impressed to input transistor 8. The transistor 8 and transistor 9 constitute a Schmitt circuit. When the output of coil 1 exceeds the threshold level of said Schmitt circuit, transistor 8 is energized and power transistor 14 is also energized via transistors 9-12. When transistor 8 is de-enrgized subsequently as the output of coil 1 is lowered, transistor 14 is also de-energized and a high voltage is produced at the secondary side of ignition coil 13, so that spark is emitted at the ignition plug. |
