| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a semiconductor switch element, a driver IC or the like from being broken when a power supply is turned on. <P>SOLUTION: An FET31 is provided. The FET takes in V<SB>CC</SB>voltage from a V<SB>CC</SB>voltage source, and the V<SB>CC</SB>voltage is outputted when the FET is actuated. The collector of the bipolar transistor 32 is connected to a gate of the FET through a resistor 33, with its emitter being grounded. A V<SB>DD</SB>voltage from a V<SB>DD</SB>voltage source is inputted in the base of the bipolar transistor 32 through a resistor 34. The V<SB>CC</SB>voltage outputted from the FET is inputted in a three-terminal regulator 35. The three-terminal regulator 35 controls for stepping down the inputted V<SB>CC</SB>voltage, to output a V<SB>AA</SB>voltage. The V<SB>CC</SB>voltage outputted from the FET is supplied to a head drive circuit, and the V<SB>AA</SB>voltage outputted from the three-terminal regulator 35 is supplied to an ink-jet head. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
