公开(公告)号：JPH06174762A

公开(公告)日：1994-06-24

申请号：JP17551393

申请日：1993-07-15

Applicant: ST MICROELECTRONICS SRL

Inventor： BORGATO PIERANDREA ,  DIAZZI CLAUDIO ,  PIDUTTI ALBINO

IPC: G01R19/12 ,  G01R19/165 ,  H02M3/156

Abstract: PURPOSE: To obtain a detection circuit where the output terminal requires no additional pin for producing an external signal by providing a sensor for detecting a current flowing through a feedback branch and proportional to the fluctuation of output voltage at the output terminal. CONSTITUTION: A detection circuit 39 in the apparatus comprises a current sensor 40 disposed between a pin 29 and the output terminal 41 of an error amplifier 27 and generating a current signal KDI proportional to the current DI of a compensation capacitor 28 at an output terminal 42. When the output voltage Vo fluctuates, e.g. it increases by DVo for example, it is detected only by a resistor 16. Consequently, the current increases by an amount DI equal to DVo /R2 and the current DI flows through the compensation capacitor 28 and detected by the current sensor 40. The current is proportional to the instantaneous fluctuation of the output voltage Vo . A detection circuit 39 is integrated conveniently on a control circuit 8 which does not require any additional pin on the package.

公开(公告)号：DE69222762D1

公开(公告)日：1997-11-20

申请号：DE69222762

申请日：1992-07-30

Applicant: ST MICROELECTRONICS SRL

Inventor： BORGATO PIERANDREA ,  DIAZZI CLAUDIO ,  PIDUTTI ALBINO

IPC: G01R19/12 ,  G01R19/165 ,  H02M3/156 ,  H02M1/14

Abstract: A circuit (39) for detecting voltage variations in relation to a set value, for devices (1), more specifically a power supply circuit, comprising an error amplifier (27) fed back by a compensating capacitor (28) which, under steady state operating conditions, is not supplied with current, and, in the presence of transient output voltage (Vo) of the device (1), is supplied with current (DI) proportional to the variation in voltage; the circuit (39) comprising a current sensor (40) connected to the compensating capacitor (28) for detecting the current (DI) through the same; and the output signal of the sensor (40) preferably being supplied to a circuit (43, 44) for limiting the variation in output voltage which, in the event the voltage variation exceeds a given threshold value (VR1), activates a control stage (31) connected to the output of the device.

公开(公告)号：DE69222762T2

公开(公告)日：1998-02-12

申请号：DE69222762

申请日：1992-07-30

Applicant: ST MICROELECTRONICS SRL

Inventor： BORGATO PIERANDREA ,  DIAZZI CLAUDIO ,  PIDUTTI ALBINO

IPC: G01R19/12 ,  G01R19/165 ,  H02M3/156 ,  H02M1/14

Abstract: A circuit (39) for detecting voltage variations in relation to a set value, for devices (1), more specifically a power supply circuit, comprising an error amplifier (27) fed back by a compensating capacitor (28) which, under steady state operating conditions, is not supplied with current, and, in the presence of transient output voltage (Vo) of the device (1), is supplied with current (DI) proportional to the variation in voltage; the circuit (39) comprising a current sensor (40) connected to the compensating capacitor (28) for detecting the current (DI) through the same; and the output signal of the sensor (40) preferably being supplied to a circuit (43, 44) for limiting the variation in output voltage which, in the event the voltage variation exceeds a given threshold value (VR1), activates a control stage (31) connected to the output of the device.