| 摘要 |
PROBLEM TO BE SOLVED: To provide a charge control circuit which can charge a secondary battery in a short time. SOLUTION: The charge control circuit performs constant-current charge, until battery voltage reaches specified voltage Vch1 higher than full-charge voltage, and then it performs charge so that the battery voltage may accord with constant-voltage-control voltage, while the constant-voltage-control voltage is lowered to the full-charge voltage Vch2 gradually accompanying the decrease of the charge current. For realizing this, a regulator circuit, which supplies a constant-voltage control circuit 42 with constant-voltage-control voltage, has a mirror circuit MC, which is connected with the junction between resistors R5 and R6 constituting a resistive potential divider. The mirror circuit MC changes the voltage-dividing ratio of the resistive potential divider according to the output of the sense amplifier A1 of a constant-current control circuit 41. Hereby, the constant-voltage-control voltage (regulator voltage ) from the regulator amplifier A4 changes continuously from Vch1 to Vch2, accompanying the decrease in the charging current. COPYRIGHT: (C)2004,JPO&NCIPI |
