POWER SUPPLY CIRCUIT, POWER SUPPLY SYSTEM, AND PORTABLE TERMINAL DEVICE

• Main Authors: TAKAGAHARA KAZUHIKO, KAWANO RYUSUKE, ISHIHARA TAKAKO, KOIZUMI HIROSHI, ONO KAZUYOSHI
• Format: Patent
• Language: English; Japanese
• Published: 12.11.2015
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

PROBLEM TO BE SOLVED: To provide a power supply device capable of stably supplying a power supply voltage without damaging the stability of a circuit as a power supply destination.SOLUTION: A power supply circuit (1) includes: an input terminal (PIN) to which a voltage is supplied; a linear regulator (10) which drops and outputs an input voltage (VBAT); a monitoring part (12) which monitors the voltage supplied to the input terminal; a detection part (13) which detects that the voltage supplied to the input terminal is less than a reference value on the basis of the monitor result of the monitoring part; and a control part (11) which controls the supply of the input voltage to the linear regulator. The control part blocks the supply of the input voltage to the linear regulator when the detection part detects that the voltage supplied to the input terminal is less than the reference value. 【課題】電源供給先の回路の安定性を損なうことなく、安定した電源電圧の供給が可能な電源装置を提供する。【解決手段】本発明に係る電源回路（１）は、電圧が供給される入力端子（ＰＩＮ）と、入力電圧（ＶＢＡＴ）を降圧して出力するリニアレギュレータ（１０）と、前記入力端子に供給された電圧を監視する監視部（１２）と、前記監視部による監視結果に基づいて前記入力端子に供給された電圧が基準値よりも低くなったことを検出する検出部（１３）と、前記リニアレギュレータに対する前記入力電圧の供給を制御する制御部（１１）とを有し、制御部は、前記検出部が前記入力端子に供給された電圧が基準値よりも低くなったことを検出したら、リニアレギュレータに対する前記入力電圧の供給を遮断することを特徴とする。【選択図】図１