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    OUTPUT CONTROL OF DC-DC CONVERTER CORRESPONDING TO FLUCTUATION IN SWITCHING FREQUENCY
    1.
    发明专利
    OUTPUT CONTROL OF DC-DC CONVERTER CORRESPONDING TO FLUCTUATION IN SWITCHING FREQUENCY 失效

    公开(公告)号：JPH10304659A

    公开(公告)日：1998-11-13

    申请号：JP9705098

    申请日：1998-04-09

    Applicant: ST MICROELECTRONICS SRL

    Inventor： ADRAGNA CLAUDIO ,  GATTAVARI GIUSEPPE ,  FAGNANI MAURO

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

    Abstract: PROBLEM TO BE SOLVED: To make the output of a DC/DC converter constant by clamping an error amplifier output signal of a control circuit to a voltage proportional to the amplitude of DC signals inversely proportional to the frequency or by giving an offset equal to a voltage difference between a constant voltage and DC signal to a signal occurred in a current sensing resistor. SOLUTION: A sawtooth wave signal generated by an oscillator is detected by a capacitor Cosc of an RC group. A process of generating a DC signal having an amplitude inversely proportional to that frequency, a process of clamping an error amplifier E/A output voltage to a voltage having an amplitude proportional to the amplitude of the DC signal, or a process of off-setting a signal in a current sensing resistor by a voltage, corresponding to the difference between the constant voltage and DC signal is carried out. By doing this, it becomes possible to obtain a method and a compensating circuit which can be easily realized independently of the characteristics of synchronous signal controlling the switching frequency, and can make the output power of a converter constant against the changes in switching frequency.

    2.
    发明专利
    未知

    公开(公告)号：DE60025324D1

    公开(公告)日：2006-03-30

    申请号：DE60025324

    申请日：2000-03-17

    Applicant: ST MICROELECTRONICS SRL

    Inventor： GATTAVARI GIUSEPPE ,  ADRAGNA CLAUDIO ,  FAGNANI MAURO

    IPC: H02M3/335

    Abstract: A method and a circuit for disabling a converter while allowing its self-recovery, the converter circuit comprising a transformer (T1) provided with an auxiliary winding (L1) self-supplying, after start-up, an integrated circuit (IC) containing the programming, driving, controlling and protecting circuitry of the converter, a start-up circuit directly connected to a power source, a rectifying circuit (D1, C1) of the voltage induced in the auxiliary winding (L1), supplying through a voltage regulator stage (R1, Z1, T1) the integrated circuit at a regulated voltage (Vreg), at least an external line comprising a sensor of an electrical or physical quantity to be monitored (NTC, Rs), biased to a reference voltage, functionally coupled to a disable input pin (A-REC) of the integrated circuit for disabling it when a certain threshold value is surpassed. The method consists in using the regulated self-supply voltage of the converter (Vreg) as biasing voltage of the external sensor line and as reference voltage of an hysteresis comparator monitoring the signal representing the monitored quantity produced an the external sensor line. Upon the switching of the hysteresis comparator the integrated converter circuit (IC) is turned off and the limiting value of the rectified voltage (Vcc) self-supplying the integrated converter circuit (IC) is markedly reduced by short-circuiting to ground a portion (Z4, Z5) of a sectionable voltage clamp chain (Z2, Z3, Z4, Z5) coupled between the output (Vcc) of the rectifying circuit (D1, C1) and a common ground node of the circuit.

    4.
    发明专利
    未知

    公开(公告)号：DE60003809D1

    公开(公告)日：2003-08-14

    申请号：DE60003809

    申请日：2000-07-28

    Applicant: ST MICROELECTRONICS SRL

    Inventor： GATTAVARI GIUSEPPE ,  ADRAGNA CLAUDIO

    IPC: H02M1/00 ,  H02M1/42

    Abstract: A converter directly connectable to the mains comprises a rectifier stage of the network voltage, a power factor correction pre-regulating circuit supplied with the rectified network voltage and producing a DC voltage of a certain nominal value, a DC-DC converter supplied with the DC voltage of a certain nominal value and producing a pre-established DC voltage on an output node, sensing means producing a signal representative of the current level of load being supplied by the converter. The power consumption of the converter is lowered by a control circuit fed with the signal representative of the level of load that generates a disabling signal of the power factor corrector pre-regulating circuit as long as the level of load does not exceed a certain pre-established threshold.

    6.
    发明专利
    未知

    公开(公告)号：ITMI20031315D0

    公开(公告)日：2003-06-27

    申请号：ITMI20031315

    申请日：2003-06-27

    Applicant: ST MICROELECTRONICS SRL

    Inventor： ADRAGNA CLAUDIO ,  GATTAVARI GIUSEPPE

    IPC: G05F1/70 ,  H02M1/00 ,  H02M1/42

    Abstract: A device is provided for the correction of the power factor in forced switching power supplies. The device includes a converter, and a first control circuit coupled with the converter so as to obtain a regulated voltage on the output terminal from an alternating network input voltage. The converter includes a power transistor, and the first control circuit is suitable for driving the power transistor in every switching cycle comprising the turn-on time and the turn-off time of the power transistor. The device for the correction of the power factor further includes a second control circuit coupled to the first control circuit and capable of modulating the turn-off time of the power transistor.

    8.
    发明专利
    未知

    公开(公告)号：DE602005016352D1

    公开(公告)日：2009-10-15

    申请号：DE602005016352

    申请日：2005-10-11

    Applicant: ST MICROELECTRONICS SRL

    Inventor： ADRAGNA CLAUDIO ,  FAGNANI MAURO ,  GATTAVARI GIUSEPPE

    IPC: H02M1/42

    Abstract: The present invention describes is a device for power factor correction in forced switching power supply unit, comprising a converter (20) and a control device (100) coupled with the converter (20) so as to obtain from an input alternating mains voltage (Vin) a direct regulated voltage (Vout) on the output terminal. The converter (20) comprises a power transistor (M) and the control device (100) comprises an error amplifier (3) having in input on the inverting terminal a first signal (Vr) proportional to the regulated voltage (Vout) and on the non-inverting terminal a reference voltage (Vref), a drive circuit (4-7, 10) of the power transistor (M) coupled with the output terminal of the error amplifier (3). The control device (100) comprises means (42, Cff, 101, Rt, 102) suitable for generating a current signal (It) representative of the effective input voltage; said current signal (It) is in input on the inverting terminal of said error amplifier (3) to vary said regulated voltage (Vout) in reply to variations of the effective input voltage.

    10.
    发明专利
    未知

    公开(公告)号：DE60003809T2

    公开(公告)日：2004-06-03

    申请号：DE60003809

    申请日：2000-07-28

    Applicant: ST MICROELECTRONICS SRL

    Inventor： GATTAVARI GIUSEPPE ,  ADRAGNA CLAUDIO

    IPC: H02M1/00 ,  H02M1/42

    Abstract: A converter directly connectable to the mains comprises a rectifier stage of the network voltage, a power factor correction pre-regulating circuit supplied with the rectified network voltage and producing a DC voltage of a certain nominal value, a DC-DC converter supplied with the DC voltage of a certain nominal value and producing a pre-established DC voltage on an output node, sensing means producing a signal representative of the current level of load being supplied by the converter. The power consumption of the converter is lowered by a control circuit fed with the signal representative of the level of load that generates a disabling signal of the power factor corrector pre-regulating circuit as long as the level of load does not exceed a certain pre-established threshold.

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