Boost capacitor for an H-bridge integrated circuit motor controller having matching characteristics with that of the low-side switching devices of the bridge
AssigneeSTMicroelectronics S.r.l.
InventorAlbino Pidutti
Life of this patent
Estimating the term…
Abstract
An H-bridge circuit having a boost capacitor coupled to the gate of the low-side driver. A driver, in the form of a switching transistor is connected between the load and ground, thus providing a low-side driver. A capacitor is coupled to the gate of the low-side driver to provide a boosted voltage for rapid turn on of the gate. The size of the capacitor selected to be similar to the size of the capacitance associated with the low-side driver transistor.
Claims21
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second voltage supply lines, said circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of a respective low-side switching device, wherein said boost capacitor enable circuit includes a boosted inverter circuit;
- and
- a pull-down circuit having a current carrying terminal connected to the switching terminal of each respective low-side switching device and having a control terminal connected as an input for grounding the switching terminal of the respective low-side switching device in response to an input signal.
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second supply lines, said circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of the respective low-side switching device;
- an additional switching device having a control terminal and first and second current carrying terminals;
- a current source coupled in series with said first and second current carrying terminals of the additional switching device;
- an additional capacitor coupled across said first and second current carrying terminals of the additional switching device;
- and
- an electrical connection between the control terminal of the additional switching device and the switching terminal of at least one of the low-side switching devices.
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second voltage supply lines, said circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of a respective low-side switching device, wherein said boost capacitor enable circuit includes a boosted inverter circuit;
- an additional switching device having a control and first and second current carrying terminals thereof, said control terminal being coupled to said first current carrying terminal;
- a current source coupled in series with said first and second current carrying terminals of said additional switching device between said first and second voltage supply lines;
- an additional capacitor coupled across said first and second current carrying terminals of said additional switching device, wherein said additional capacitor is effective to reduce a control terminal-to-second current carrying terminal capacitance of said additional switching device;
- and
- an electrical connection between the control terminal of the additional switching device and the switching terminal of the respective low-side switching device.
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second voltage supply lines, said circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of a respective low-side switching device, wherein said boost capacitor enable circuit includes a boosted inverter circuit;
- a current source having an output coupled to the switching terminal of a low-side switching device;
- and
- a transfer gate selectively coupling the output of the current source to the switching terminal under control of an input signal.
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second voltage supply lines, said integrated H-bridge circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of a respective low-side switching device, wherein said boost capacitor enable circuit includes a boosted inverter circuit;
- an additional switching device coupled to one of the low-side switching devices and having a control and first and second current carrying terminals;
- and
- an additional capacitor coupled across said first and second current carrying terminals of said additional switching device.
An integrated H-bridge circuit including first and second pairs of high-side and low-side switching devices to selectively couple an electrical load between first and second voltage supply lines, said circuit comprising:
- a boost capacitor coupled to a switching terminal of each of said low-side switching devices, said boost capacitor having a capacitance substantially equivalent to an input capacitance of an associated one of said low-side switching devices;
- a boost capacitor enable circuit coupled to the boost capacitor to enable a boosted capacitor voltage to be provided on the switching terminal of a respective low-side switching device, wherein said boost capacitor enable circuit includes a boosted inverter circuit;
- an additional switching device having a control and first and second current carrying terminals thereof, said control terminal being coupled to said first current carrying terminal;
- a current source coupled in series with said first and second current carrying terminals of said additional switching device between said first and second voltage supply lines;
- an additional capacitor coupled across said first and second current carrying terminals of said additional switching device;
- and
- an electrical connection between the control terminal of the additional switching device and the switching terminal of the respective low-side switching device.
Dependencies are inferred from the claim text.