| 摘要 |
A level shifting circuit converts an input signal that varies between ground and a first voltage to a shifted signal that varies between ground and a second voltage higher than the first voltage. The level shifting circuit has two branches, in each of which a p-channel transistor and two n-channel transistors are connected in series between the second voltage and ground. When the two n-channel transistors in each branch are turned off, a clamping circuit clamps the node between them to the first voltage level, so that neither n-channel transistor has to withstand the full difference between the second voltage and ground. The level shifting circuit can accordingly be fabricated with transistors of small size, reducing the cost of driving circuits, light-emitting-diode print heads, and image forming apparatus in which the level shifting circuit is used.
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