CONSTANT VOLTAGE CIRCUIT

• Main Author: SHINOHARA MASATOSHI
• Format: Patent
• Language: English; Japanese
• Published: 04.04.2019
• Subjects: CONTROLLING; PHYSICS; REGULATING; SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES

To provide a constant voltage circuit that can reduce fluctuation of output voltage.SOLUTION: The constant voltage circuit 30 includes a first resistance R1 that includes: a first terminal connected to a power supply voltage terminal and a second terminal connected to the first node n1; a first transistor Q2 of a first electrical conduction shape that includes the first terminal connected to the power supply voltage terminal, the second terminal connected to the second node n6 and a control terminal connected to the first node n1; a first diode in serial connection between the first node n1 and the ground voltage terminal; a Zener diode Dz1 and a second transistor Q4 of a second electrical conduction shape which is different from the first electrical conduction shape in serial connection between the first node n1 and the ground voltage terminal; a second resistance R4 and a third resistance Q3 of the first electrical conduction shape in serial connection between the first node n1 and the ground voltage terminal; and a third resistance R2 and a fourth resistance R3 in serial connection between the second node n6 and the ground voltage terminal.SELECTED DRAWING: Figure 2 【課題】出力電圧の変動を低減することができる定電圧回路を提供する。【解決手段】定電圧回路３０は、電源電圧端子に接続される第１端子と、第１ノードｎ１に接続される第２端子とを含む第１抵抗Ｒ１と、電源電圧端子に接続される第１端子と、第２ノードｎ６に接続される第２端子と、第１ノードｎ１に接続される制御端子とを含む第１導電形の第１トランジスタＱ２と、第１ノードｎ１と接地電圧端子との間に直列に接続される第１ダイオードと、第１ノードｎ１と接地電圧端子との間に直列に接続されるツェナーダイオードＤｚ１及び第１導電形と異なる第２導電形の第２トランジスタＱ４と、第１ノードｎ１と接地電圧端子との間に直列に接続される第２抵抗Ｒ４及び第１導電形の第３トランジスタＱ３と、第２ノードｎ６と接地電圧端子との間に直列に接続される第３抵抗Ｒ２及び第４抵抗Ｒ３と、を備える。【選択図】図２