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US 2024/0178754 A1Published application
Power converter
AssigneesNexperia B.V., Nexperia Technology (Shanghai) Ltd.
InventorsYasuo Matsumura, Katsuya Goto
Life of this patent
Estimating the term…
Abstract
The present disclosure relates to a power converter and to a buck DC-to-DC power converter, such as a constant-on-time (COT) Buck DC-to-DC power converter. Additionally, a COT Buck DC-to-DC converter is provided which has a seamless transition between the normal operation mode and the 100% duty operation mode.
Claims18
A power converter, comprising:
- a switching circuit configured to convert an input voltage into an output voltage, the switch circuit comprising a high side switch, a low side switch, and a switching node between the high side switch and the low side switch;
- a first comparator circuit configured to receive a reference voltage signal and a feedback voltage signal indicative of the output voltage, the first comparator circuit configured to generate a first comparing signal based upon a comparison of the feedback voltage signal and the reference voltage signal;
- a second comparator circuit configured to receive a ramp voltage signal based upon an integration of a phase signal from the switching node, and an emulated output voltage signal based upon the phase signal, the second comparator circuit configured to generate a second comparing signal based upon a comparison of the ramp voltage signal and the emulated output voltage signal;
- a mode control circuit configured to generate a state indication signal indicative of whether a ratio of the output voltage to the input voltage exceeds a predetermined threshold ratio;
- and
- a logic circuit configured to generate a switch control signal to control the switching circuit based upon the first comparing signal, the second comparing signal and the state indication signal, wherein the switch control signal is configured to cause the switching circuit to transition from a first operation mode to a second operation mode in response to a change of value of the state indication signal indicating that the ratio rises across the predetermined threshold ratio, and wherein the switch control signal is configured so that during the first operation mode, an end of on-time of the high side switch in each switching cycle of the high side switch is determined by the second comparing signal, and during the second operation mode, an end of on-time of the high side switch in each switching cycle is determined by the first comparing signal.
3 more elements
A controller for a switching circuit, wherein the switching circuit converts an input voltage into an output voltage, and comprises a high side switch, a low side switch, and a switching node between the high side switch and the low side switch, wherein the controller comprises:
- a first comparator circuit configured to receive a reference voltage signal and a feedback voltage signal indicative of the output voltage, the first comparator circuit configured to generate a first comparing signal based upon a comparison of the feedback voltage signal and the reference voltage signal;
- a second comparator circuit configured to receive a ramp voltage signal based upon an integration of a phase signal from the switching node, and an emulated output voltage signal based upon the phase signal, the second comparator circuit configured to generate a second comparing signal based upon a comparison of the ramp voltage signal and the emulated output voltage signal;
- a mode control circuit configured to generate a state indication signal indicative of whether a ratio of the output voltage to the input voltage exceeds a predetermined threshold ratio;
- and
- a logic circuit configured to generate a switch control signal for controlling the switching circuit based upon the first comparing signal, the second comparing signal and the state indication signal, wherein the switch control signal is configured to cause the switching circuit to transition from a first operation mode to a second operation mode in response to a change of value of the state indication signal indicating that the ratio rises across the predetermined threshold ratio, and wherein the switch control signal is configured so that during the first operation mode, an end of on-time of the high side switch in each switching cycle of the high side switch is determined by the second comparing signal, and during the second operation mode, an end of on-time of the high side switch in each switching cycle is determined by the first comparing signal.
2 more elements
A method for controlling a switching circuit, wherein the switching circuit converts an input voltage into an output voltage, and comprises a high side switch, a low side switch, and a switching node between the high side switch and the low side switch, the method comprising the steps of:
- generating a first comparing signal by comparing a feedback voltage signal indicative of the output voltage with a reference voltage signal;
- generating a second comparing signal by comparing a ramp voltage signal based upon an integration of a phase signal from the switching node with an emulated output voltage signal based upon the phase signal;
- generating a state indication signal indicative of whether a ratio of the output voltage to the input voltage exceeds a predetermined threshold ratio;
- and
- generating a switch control signal for controlling the switching circuit based upon the first comparing signal, the second comparing signal and the state indication signal, wherein the switch control signal is configured to cause the switching circuit to transition from a first operation mode to a second operation mode in response to a change of value of the state indication signal indicating that the ratio rises across the predetermined threshold ratio, and wherein the switch control signal is configured so that during the first operation mode, an end of on-time of the high side switch in each switching cycle of the high side switch is determined by the second comparing signal, and during the second operation mode, an end of on-time of the high side switch in each switching cycle is determined by the first comparing signal.
2 more elements
Dependencies are inferred from the claim text.