Title:
DC-DC CONVERTER
Document Type and Number:
Japanese Patent JP3233035
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a DC-DC converter in which a switching element can be driven perfectly even when the input voltage drops to decrease the output current.
SOLUTION: A bootstrap circuit 2 is connected between the drain and source of an N-MOSFET Q1, and an FET drive circuit 3 is connected between the gate of the N-MOSFET Q1 and the joint of a diode DB and a capacitor CB comprising the bootstrap circuit 2. A smoothing circuit 1 comprising a diode D1, a coil L1 and an output circuit Co and a voltage dividing resistor 4 for detecting the output voltage comprising resistors R1, R2 are connected to the output side of the N-MOSFET Q1. Furthermore, an error amplifier 5 and a pulse width modulation circuit 6 are connected between the FET drive circuit 3 and the joint of the resistors R1, R2 comprising the voltage dividing resistor 4. The pulse width modulation circuit 6 is also connected with a variable frequency circuit 11.
Inventors:
Yasuyuki Morishima
Masanari Tago
Masanari Tago
Application Number:
JP21132696A
Publication Date:
November 26, 2001
Filing Date:
August 09, 1996
Export Citation:
Assignee:
MURATA MANUFACTURING CO.,LTD.
International Classes:
H02J1/00; H02M3/155; (IPC1-7): H02M3/155; H02J1/00
Domestic Patent References:
| JP5304768A | ||||
| JP9285110A |