BATTERY MANAGEMENT SYSTEM WITH MOSFET BOOST SYSTEM

• US 20120274395A1
• Filed: 04/27/2012
• Published: 11/01/2012
• Est. Priority Date: 04/28/2011
• Status: Active Grant

• Current Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Original Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Inventors: Deam, David
• Granted Patent: US 8,729,957 B2
• Time in Patent Office: Days
• US Class Current: 327/538
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0036 using connection detecting circuits H02J7/0034 takes precedence
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 1/36 Means for starting or stopping converters
• CPC Class Codes: H03K 17/302 in field-effect transistor switches
• CPC Class Codes: H03K 2217/0027 Measuring means of, e.g. currents through or voltages across the switch
• CPC Class Codes: H03K 2217/0054 Gating switches, e.g. pass gates
• CPC Class Codes: H03K 2217/0081 Power supply means, e.g. to the switch driver

Abstract

A boost converter for driving the gate of n-channel MOSFET power devices is described. The boost converter includes a monitoring circuit and a kick start circuit to quickly bring the boost converter online when required to drive the MOSFET on.

Claims

1. A boost system for driving a high side n-channel MOSFET, comprising:

a boost converter configured to supply a boost voltage to a gate of an n-channel MOSFET;

a boost converter power supply for providing a first current to the boost converter to power the boost converter;

a second boost converter power supply for providing a second current to the boost converter, the second current being larger than the first current, the second boost converter power supply operating for a selected period of time to start the boost converter until the output of the boost converter reaches a selected voltage level.

2. The boost system of claim 1, further comprising a voltage monitoring circuit for monitoring the output of the boost converter.

3. The boost system of claim 2, further comprising a switch disposed between the boost converter and the gate of the n-channel MOSFET, the switch responsive to a signal from the voltage monitoring circuit to provide a voltage to the gate of the n-channel MOSFET when the voltage monitoring circuit determines the output of the boost converter exceeds a selected threshold and is stable.

4. The boost system of claim 1, wherein the first current is about 2 milliamps.

5. The boost system of claim 1, wherein the second current is about 30 milliamps

6. The boost system of claim 1, wherein the second boost converter power supply includes an RC timing circuit that provides for current flow from the second boost converter power supply for a selected period of time.

7. The boost system of claim 1, wherein the second boost converter power supply includes a pull down resistor, a switch, and an RC timing circuit, with the pull down resistor connected to the output of the first boost converter power supply.

8. The boost system of claim 1, further comprising a boost enable switch, the boost enable switch being responsive to a signal from a processor to turn on the first and second boost converter power supplies.

9. The boost system of claim 2, wherein the voltage monitoring circuit includes a means for monitoring hysteresis in the circuit.

10. The boost system of claim 1, wherein the first current is about 2.5 milliamps.

11. A compact, high power battery utilizing the boost system of claim 1.

12. The compact, high power battery of claim 11, wherein the battery has a weight less than or equal to three pounds.

13. The compact, high power battery of claim 11, wherein the battery has a weight to energy ratio in the range of 0.06 pounds/watt hour and 0.03 pounds/watt hour.

14. The compact, high power battery of claim 13, wherein the weight to energy ratio is approximately 0.0357 pounds/watt hour.

15. The compact high power battery of claim 11, wherein the battery has a weight to power ratio in the range of 0.002 pounds/watt and 0.0015 pounds/watt.

16. The compact high power battery of claim 11, wherein the battery has a weight to power ratio of approximately 0.00167 pounds/watt.