| 摘要 |
The present invention relates to a drive circuit for a switch (T) connected to a rectifier arrangement in a switching converter which provides an output voltage (Vout) from an input voltage (Vin), the drive circuit having the following features: a controller arrangement ( 40 ) having at least one control amplifier (OTA 1 ) and a compensation network ( 41 ) having at least one capacitor (C 4 , C 5 ), a signal dependent on the output voltage (Vout) being fed to said controller arrangement and the latter providing a control signal (S 4 ), a protection circuit ( 30 ), which is designed to detect at least one critical state of the switching converter and which provides a protection signal (S 3 ) in a manner dependent on the presence of a critical state, the protection circuit ( 30 ) having a discharge circuit ( 32 ) coupled to the compensation network ( 41 ), a signal generating circuit ( 20 ), to which the control signal (S 4 ) and the protection signal (S 3 ) are fed and which provides a drive signal (S 5 ) having drive pulses according to the protection signal, the duty ratio of which drive signal is dependent on the control signal (S 4 ).
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