HIGH SIDE DRIVER WITHOUT DEDICATED SUPPLY IN HIGH VOLTAGE APPLICATIONS

• US 20180234015A1
• Filed: 02/14/2017
• Published: 08/16/2018
• Est. Priority Date: 02/14/2017
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Degen, Peter Theodorus Johannes
• Granted Patent: US 10,103,629 B2
• Time in Patent Office: Days
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: H03K 17/063 in field-effect transistor switches
• CPC Class Codes: H03K 19/01714 by bootstrapping, i.e. by positive feed-back
• CPC Class Codes: H03K 2217/0045 Full bridges, determining the direction of the current through the load
• CPC Class Codes: H03K 2217/0063 High side switches, i.e. the higher potential [DC] or life wire [AC] being directly connected to the switch and not via the load
• CPC Class Codes: H03K 2217/0072 Low side switches, i.e. the lower potential [DC] or neutral wire [AC] being directly connected to the switch and not via the load
• CPC Class Codes: H03K 2217/0081 Power supply means, e.g. to the switch driver
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A DC-to-DC converter is disclosed. The SMPS driver includes a highside switch having a first terminal, a second terminal and a gate. The first terminal is coupled to an input voltage terminal. The SMPS driver further includes a lowside switch having a first terminal, a second terminal and a gate. The first terminal of the lowside switch is coupled to the second terminal of the highside switch and the second terminal of the lowside switch is coupled to ground. A diode is coupled to the gate of the lowside switch on one side and to a capacitor on the other side. An integrated circuit (IC) is included to generate control signals for switching the highside switch and the lowside switch. The IC includes a highside supply pin, a highside gate control pin, a half bridge pin, a lowside gate control pin and a ground pin. The gate of the lowside switch is coupled to the lowside gate control pin, the highside supply pin is coupled to the diode and the capacitor is coupled to the half bridge pin.

Claims

1. A DC-to-DC converter, comprising:

a highside switch having a first terminal, a second terminal and a gate, wherein the first terminal is coupled to an input voltage terminal;

a lowside switch having a first terminal, a second terminal and a gate, wherein the first terminal of the lowside switch is coupled to the second terminal of the highside switch and the second terminal of the lowside switch is coupled to ground;

a diode coupled to the gate of the lowside switch on one side and to a capacitor on the other side; and

an integrated circuit (IC) configured and arranged to generate control signals for switching the highside switch and the lowside switch via one of the control signals coupled to activate the lowside switch and to charge the capacitor, wherein the IC includes a highside supply pin, a half bridge pin, a lowside gate control pin and a ground pin, wherein the gate of the lowside switch and the capacitor are coupled to receive the control signal.

2. The DC-to-DC converter of claim 1, wherein the IC includes a first driver that is coupled to the half bridge pin and the highside supply pin, wherein in response to the control signal switching, the lowside switch is configured and arranged to deactivate and the integrated circuit is configured and arranged to use the charge of the capacitor to activate the highside switch via its gate.

3. The DC-to-DC converter of claim 2, wherein the IC further includes a highside gate control pin, and the gate of the lowside switch is coupled to the lowside gate control pin, the highside supply pin is coupled to the diode and the capacitor is coupled to the half bridge pin, and the first driver is controlled by a binary control signal that cause the first driver to couple the half bridge pin or the highside supply pin to the highside gate control pin.

4. The DC-to-DC converter of claim 1, wherein the IC includes a second driver that is coupled to the lowside gate control pin, a switch voltage line and the ground pin.

5. The DC-to-DC converter of claim 4, wherein the second driver is controlled by a binary control signal that cause the second driver to couple the ground pin or the switch voltage line to the lowside gate control pin.

6. The DC-to-DC converter of claim 4, wherein the switch voltage line is configured to carry a switching voltage that is lower than the voltage at the input voltage terminal.

7. The DC-to-DC converter of claim 1, wherein the input voltage terminal is configured to accept up to 400V.

8. The DC-to-DC converter of claim 1, wherein the highside switch and the lowside switch are configured and arranged to be activated in response to a voltage at their respective gates in the range of 8V to 20V.

9. A switch mode power supply (SMPS) comprising the DC-to-DC converter of claim 1.

18. The DC-to-DC converter of claim 1, wherein the capacitor is configured and arranged to charge via energy from the lowside switch.

19. The DC-to-DC converter of claim 1, wherein the IC is configured and arranged to control the diode and the capacitor in:

a first mode in which the capacitor is charged via energy from the gate of the lowside switch; and

a second mode in which the charge at the capacitor from the first mode is used to activate the highside switch.

20. The DC-to-DC converter of claim 19, wherein the IC is configured and arranged to control the diode and the capacitor in the second mode in response to the control signal switching and transitioning the lowside switch to deactivate.

10. A DC-to-DC converter, comprising:

two highside switches, each having a first terminal, a second terminal and a gate, wherein the first terminal is coupled to an input voltage terminal;

two lowside switches, each having a first terminal, a second terminal and a gate, wherein the first terminal of the lowside switch is coupled to the second terminal of the highside switch and the second terminal of the lowside switch is coupled to ground;

two diodes, each coupled to the gate of one of the lowside switches on one side and to a capacitor on the other side; and

an integrated circuit (IC) configured and arranged to generate control signals for switching each of the highside switches and each of the lowside switches, wherein the IC is configured and arranged to generate a first control signal to activate the lowside switches and to charge the capacitors, wherein the IC includes an IC package having two highside supply pins, two highside gate control pins, two half bridge pins, two lowside gate control pins and a ground pin, wherein the gate of the each of the lowside switches and the capacitors are respectively coupled to receive the first control signal.

11. The DC-to-DC converter of claim 10, wherein the IC includes a first driver that is coupled to one of the highside gate control pins, one of the half bridge pins and one of the highside supply pins, wherein the gate of the each of the lowside switches is coupled to one of the lowside gate control pins, one of the highside supply pins is coupled to one of the diodes and the capacitor is coupled to one of the half bridge pins.

12. The DC-to-DC converter of claim 11, wherein the first driver is controlled by a binary control signal that cause the first driver to couple one of the half bridge pins or one of the highside supply pins to one of the highside gate control pins.

13. The DC-to-DC converter of claim 10, wherein the IC includes a second driver that is coupled to one the lowside gate control pins, a switch voltage line and the ground pin.

14. The DC-to-DC converter of claim 13, wherein the second driver is controlled by a binary control signal that cause the second driver to couple the ground pin or the switch voltage line to one of the lowside gate control pins.

15. The DC-to-DC converter of claim 10, wherein the highside switches and the lowside switches are switchable through a voltage in the range of 8V to 20V.

16. The DC-to-DC converter of claim 10, wherein in response to the control signal switching, the lowside switches are configured and arranged to deactivate and the IC is configured and arranged to use the charge of the capacitor to activate the highside switches via their respective gates.

17. The DC-to-DC converter of claim 10, wherein the capacitors are configured and arranged to charge via energy from the lowside switch and the IC is configured and arranged to provide a second control signal and to use the charge of the capacitors to activate the highside switches.