| 摘要 |
A voltage regulator circuit for generating a regulated output DC voltage from a non-regulated DC or AC voltage, comprises an input rectifier circuit for rectifying the non-regulated AC voltage and a series regulator, containing a gate-controllable transistor, which regulates the output voltage supplied to it by the rectifier to a first voltage value. The transistor of the series regulator is a field-effect transistor (20) which in the ON condition charges a charging capacitor (46), the charging voltage of which forms the regulated output voltage. Connected to the gate terminal (21) of the field-effect transistor is a first threshold circuit (26, 28, 30, 32) receiving the non-regulated DC voltage which applies to this gate terminal (21) a voltage turning OFF the field-effect transistor (20) as soon as the non-regulated DC voltage exceeds a predetermined threshold value. Furthermore, connected to the gate terminal (21) of the field-effect transistor (20) is a second threshold circuit (36, 38, 40, 42) receiving the regulated output DC voltage which applies to this gate terminal (21) a voltage turning OFF the field-effect transistor (20) as soon as the regulated output DC voltage exceeds a predetermined design value.
|
