Parallel synchronized operation for a half-bridge configuration in a switch mode power supply
AssigneeRenesas Electronics America Inc.
InventorTetsuo Sato
Life of this patent
Estimating the term…
Abstract
One or more embodiments relate to a circuit that can be used to prevent cross conduction in an SMPS including multiple half-bridge modules connected in parallel to a single output inductor and driven by a single pulse width modulation (PWM) signal. According to certain aspects, each high-side driver and low-side driver in a single half-bridge module is synchronized in their switching with corresponding high-side drivers and low-side drivers in other half-bridge modules.
Claims20
A cross conduction prevention circuit for a switch-mode power supply coupled to receive an input voltage, an input current, and provide an output voltage and an output current to a load comprising a plurality of half-bridge circuits connected in parallel,
- each of the plurality of the half-bridge circuits comprising:
- a high-side (HS) driver and a low-side (LS) driver,
- the HS driver and the LS driver both having an on state and an off state,
- the HS driver and the LS driver both coupled to change from the on state to the off state and vice versa in response to a pulse width modulation signal (PWM) signal,
- the cross conduction prevention circuit comprising:
- each HS driver in each half-bridge circuit being configured to output its own state and configured to sense a combined state of all the LS drivers via an LS synchronizing (sync) signal before turning on,
- each LS driver in each half-bridge circuit being configured to output its own state and also configured to sense a combined state of all the HS drivers via a LS synchronizing signal before turning on,
- wherein all the HS drivers are coupled to change from the off state to the on state in a synchronous manner only when the combined state of all the LS drivers is off, and
- wherein all the LS drivers are coupled to change from the off state to the on state in a synchronous manner only when the combined state of all the HS drivers is off to prevent any current from any HS driver to any LS driver or vice versa.
A method for preventing cross conduction for a switch-mode power supply coupled to receive an input voltage, an input current, and provide an output voltage and an output current to a load comprising a plurality of half-bridge circuits connected in parallel,
- each of the plurality of the half-bridge circuits comprising:
- a high-side (HS) driver and a low-side (LS) driver,
- the HS driver and the LS driver both having an on state and an off state,
- the HS driver and the LS driver both coupled to change from the on state to the off state and vice versa in response to a pulse width modulation signal (PWM) signal,
- the method comprising:
- configuring each HS driver in each half-bridge circuit to output its own state and
- sensing a combined state of all the LS drivers via an LS synchronizing (sync) signal before being turned on,
- configuring each LS driver in each half-bridge circuit to output its own state and sensing a combined state of all the HS drivers via a LS synchronizing signal before being turned on,
- coupling all the HS drivers to change from the off state to the on state in a synchronous manner only when the combined state of all the LS drivers is off,
- coupling all the LS drivers to change from the off state to the on state in a synchronous manner only when the combined state of all the HS drivers is off, and
- preventing any current from any HS driver to any LS driver or vice versa.
A cross conduction prevention system for a switch-mode power supply to receive an input voltage, an input current, and provide an output voltage and an output current to a load comprising a plurality of half-bridge circuits connected in parallel,
- each of the plurality of the half-bridge circuits comprising:
- a high-side (HS) driver and a low-side (LS) driver,
- the HS driver and the LS driver both having an on state and an off state,
- the HS driver and the LS driver both coupled to change from the on state to the off state and vice versa in response to a pulse width modulation signal (PWM) signal,
- the cross conduction prevention circuit comprising:
- each HS driver in each half-bridge circuit being configured to output its own state and configured to sense a combined state of all the LS drivers via an LS synchronizing (sync) signal before turning on,
- each LS driver in each half-bridge circuit being configured to output its own state and also configured to sense a combined state of all the HS drivers via a LS synchronizing signal before turning on,
- wherein all the HS drivers are coupled to change from the off state to the on state in a synchronous manner only when the combined state of all the LS drivers is off, and
- wherein all the LS drivers are coupled to change from the off state to the on state in a synchronous manner only when the combined state of all the HS drivers is off to prevent any current from any HS driver to any LS driver or vice versa.
Dependencies are inferred from the claim text.