| 摘要 |
PROBLEM TO BE SOLVED: To avoid the misoperation of a DC-DC converter and to eliminate the use of a switch and a circuit, which are out of rating. SOLUTION: A control circuit of the pulse width modulation DC-DC converter comprises: a current amplifier for generating a signal corresponding to control of input voltage and a switch signal; a compensator for generating a signal in accordance with a current amplifier output signal and a modulation signal; a comparator for comparing a compensator output signal and the amplifier output signal and generating a reset signal; a latch circuit for latching the signal in accordance with the control of the reset signal and a setting signal; a timing generator having a first low potential pulse amplified at the time of a heavy load state and having a second low potential pulse which is separately amplified at the time of a light state; a driving circuit for generating a driving signal in accordance with a latch circuit output signal, driving the switch, generating the switch signal and controlling the current amplifier; and a pressure lowering circuit and a differential amplifier for generating a signal in accordance with control of output voltage of the pressure lowering circuit and reference voltage. COPYRIGHT: (C)2005,JPO&NCIPI
|
