| 摘要 |
PROBLEM TO BE SOLVED: To reduce a reactive current when a voltage converting operation stops, and improve the power efficiency by providing a control function for preventing a reverse current generated during a low load and flowing from an output terminal to a power supply in a voltage boosting voltage converter used for a cellular phone and a PDA. SOLUTION: Voltage potentials of a source and a drain of a switching transistor between a voltage boosting coil and the output terminal are compared. When the reverse current is generated and flows from the output terminal to the power supply, a control circuit operates so as to turn off the switching transistor and prevents the reverse current generated during the low load and flowing from the output terminal to the power supply. COPYRIGHT: (C)2005,JPO&NCIPI
|
