Power converter controller with input current slope adjustment
First Claim
1. A transient event detector to detect whether a magnitude of a slope of an input current signal exceeds a slope threshold, the transient event detector comprising:
- a first reference generator coupled to scale the input current signal to generate a first reference current signal that tracks the input current signal;
an adjustable low-pass filter circuit coupled to receive the input current signal and to generate a filtered input current signal in response thereto, wherein the adjustable low-pass filter circuit has a cutoff frequency such that a magnitude of a slope of the filtered input current signal is less than the magnitude of the slope of the input current signal during a transient event; and
a first comparator coupled to generate an event detection signal that indicates the presence of the transient event in response to a value of the filtered input current signal reaching a value of the first reference current signal, wherein the adjustable low-pass filter circuit is configured to increase the cutoff frequency in response to the event detection signal indicating the presence of the transient event to increase the magnitude of the slope of the filtered input current signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A transient event detector includes a first reference generator, an adjustable low-pass filter, and a comparator. The first reference generator coupled to scale the input current signal to generate a first reference current signal that tracks the input current signal. The adjustable low-pass filter circuit is coupled to receive the input current signal and to generate a filtered input current signal such that a magnitude of a slope of the filtered input current signal is less than the magnitude of the slope of the input current signal during a transient event. The first comparator is coupled to generate an event detection signal that indicates the presence of the transient event in response to a value of the filtered input current signal reaching a value of the first reference current signal. The adjustable low-pass filter circuit is configured to increase the cutoff frequency in response to the event detection signal.
-
Citations
22 Claims
-
1. A transient event detector to detect whether a magnitude of a slope of an input current signal exceeds a slope threshold, the transient event detector comprising:
-
a first reference generator coupled to scale the input current signal to generate a first reference current signal that tracks the input current signal; an adjustable low-pass filter circuit coupled to receive the input current signal and to generate a filtered input current signal in response thereto, wherein the adjustable low-pass filter circuit has a cutoff frequency such that a magnitude of a slope of the filtered input current signal is less than the magnitude of the slope of the input current signal during a transient event; and a first comparator coupled to generate an event detection signal that indicates the presence of the transient event in response to a value of the filtered input current signal reaching a value of the first reference current signal, wherein the adjustable low-pass filter circuit is configured to increase the cutoff frequency in response to the event detection signal indicating the presence of the transient event to increase the magnitude of the slope of the filtered input current signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An input control circuit for use in a controller of a power converter that includes a variable current circuit coupled to conduct a variable current between input terminals of the power converter, the input control circuit comprising:
-
a current source coupled to selectively provide an analog current signal to the variable current circuit in response to an enable signal; and a transient event detector coupled to receive an input current signal representative of a current that is input to the input terminals of the power converter and to generate the enable signal in response to a magnitude of a slope of the input current signal exceeding a slope threshold, wherein the variable current circuit is configured to increase the variable current in response to the analog current signal to reduce the magnitude of the slope of the input current signal, wherein the transient event detector comprises; a first reference generator coupled to scale the input current signal to generate a first reference current signal that tracks the input current signal; an adjustable low-pass filter circuit coupled to receive the input current signal and to generate a filtered input current signal in response thereto, wherein the adjustable low-pass filter circuit has a cutoff frequency such that a magnitude of a slope of the filtered input current signal is less than the magnitude of the slope of the input current signal during a transient event; and a first comparator coupled to generate the enable signal in response to a value of the filtered input current signal reaching a value of the first reference current signal, wherein the adjustable low-pass filter circuit is configured to increase the cutoff frequency in response to the enable signal to increase the magnitude of the slope of the filtered input current signal. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. A power converter, comprising:
-
a variable current circuit coupled to conduct a variable current between input terminals of the power converter; a controller coupled to the variable current circuit, the controller including; a current source coupled to selectively provide an analog current signal to the variable current circuit in response to an enable signal; and a transient event detector coupled to receive an input current signal representative of current that is input to the input terminals of the power converter and to generate the enable signal in response to a magnitude of a slope of the input current signal exceeding a slope threshold, wherein the variable current circuit is configured to increase the variable current in response to the analog current signal to reduce the magnitude of the slope of the input current signal; an energy transfer element coupled between an input and an output of the power converter; and a power switch coupled to the energy transfer element, wherein the controller further comprises a drive signal generator to generate a drive signal to control switching of the power switch to control a transfer of energy across the energy transfer element from the input to the output of the power converter. - View Dependent Claims (18)
-
-
19. A bleeder controller for controlling a magnitude of a variable current conducted by bleeder circuitry between input terminals of a device, wherein the magnitude of the variable current is controllable in response to a control signal, the bleeder controller comprising:
-
a control signal output to be coupled to output the control signal to the bleeder circuitry; an input current sense input to be coupled to receive an input current sense signal representative of the current input into the input terminals of the device; a low pass filter to low pass filter the input current sense signal and output a filtered input current sense signal; a comparator to compare the filtered input current sense signal with a version of the input current sense signal and to react to higher frequency components in the version of the input current sense signal, wherein the higher frequency components have been filtered from the filtered input current sense signal by the low pass filter; and control signal circuitry to set the control signal that is output to the control signal output, the control signal circuitry to set the control signal such that conduction of the variable current between the input terminals is responsive to the reaction to the higher frequency components by the comparator. - View Dependent Claims (20, 21, 22)
-
Specification