| 摘要 |
PROBLEM TO BE SOLVED: To provide a high voltage-resistant level shift circuit that decreases the gate-source voltage of an N-channel or P-channel transistor(TR), with a voltage produced by a current flowing to a 1st or 2nd voltage generating means so as to reduce generated heat in the TR. SOLUTION: Figure shows the high voltage-resistant level shift circuit. A resistor or a constant current source employing a depletion mode MOSFET or the like is preferably employed for RN1, RP1 being voltage generating means and RN2, RP2 being load means. A Zener diode may be used for ZN1, ZP1 which are voltage-limiting means but it is superior to employ a MOS diode (a diode resulting from short-circuiting a source and a gate of a MOSFET) for the ZN1, ZP1, because a Zener voltage is suppressed to be lower. RN3, RP3 being current limit means are resistors and added to the ZN1, ZP1 which are the MOS diodes, in order to limit a current flowing through the ZN1, ZP1. However, when there is no need to limit the flowing current, naturally the resistors need not be added. |
