公开(公告)号：AU2002347601A1

公开(公告)日：2004-04-08

申请号：AU2002347601

申请日：2002-09-20

Applicant: ST MICROELECTRONICS SRL

Inventor： ADRAGNA CLAUDIO ,  FAGNANI MAURO ,  PIDUTTI ALBINO

IPC: H02M1/00 ,  H02M1/42

Abstract: A power factor correction device for switching power supplies is described, which comprises a converter ( 20 ) and a control device ( 100; 200; 300 ) coupled with said converter ( 20 ) in such a way as to obtain from a input network alternated voltage (Vin) a direct regulated voltage (Vout) at the output terminal. The converter ( 20 ) comprises a power transistor (M) and the control device ( 100; 200; 300 ) comprises an error amplifier ( 3 ) having in input at the inverting terminal a first signal (Vr) proportional to said regulated voltage (Vout) and at the non-inverting terminal a voltage reference (Vref), at least one capacitor (C) having a first terminal and a second terminal which are coupled respectively with the inverting terminal and the output terminal ( 31 ) of the error amplifier ( 3 ) and a driving circuit ( 4-6 ) of said power transistor (M) which is coupled with the second terminal of said capacitor (C). The control device ( 100; 200; 300 ) comprises interruption means (SW) placed between the output terminal ( 31 ) of said error amplifier ( 3 ) and the second terminal of said capacitor (C) and control means ( 103; 103, 301-303 ) able to activate said interruption means (SW) so as to control the interruption of the connection between the error amplifier ( 3 ) and said driving circuit ( 4-6 ) for at least one time period (T) lower than the time period (Tciclo) in which said control device ( 100; 200; 300 ) is operative.

公开(公告)号：DE69724094D1

公开(公告)日：2003-09-18

申请号：DE69724094

申请日：1997-04-09

Applicant: ST MICROELECTRONICS SRL

Inventor： ADRAGNA CLAUDIO ,  GATTAVARI GIUSEPPE ,  FAGNANI MAURO

IPC: H02M3/28 ,  H02M3/335 ,  H04N3/185

Abstract: The power output of a static DC_DC converter employing a current mode PWM controller is controlled upon the varying of the switching frequency, by detecting the sawtooth signal produced by the local oscillator generating a DC signal with amplitude inversely proportional to the frequency and by alternatively clamping the output voltage of the error amplifier of the PWM controller at a voltage proportional to the amplitude of said DC signal or by offsetting the signal present on the currents sensing resistor by a voltage corresponding to the difference between a constant voltage and said DC signal.

公开(公告)号：ITVA930023A1

公开(公告)日：1995-04-24

申请号：ITVA930023

申请日：1993-10-22

Applicant: ST MICROELECTRONICS SRL

Inventor： FAGNANI MAURO ,  FERRARIO BRUNO ,  SANDRI PAOLO

IPC: H03F3/343 ,  H03F1/00 ,  H03F1/30