Switching power converter controller with watchdog timer

• US 6,819,011 B2
• Filed: 11/14/2002
• Issued: 11/16/2004
• Est. Priority Date: 11/14/2002
• Status: Expired due to Fees

• Current Assignee: Exar Corporation (Maxlinear Incorporated)
• Original Assignee: FYRE Storm Incorporated (Maxlinear Incorporated)
• Inventors: Nohr, Mark J., Kernahan, Kent
• Primary Examiner(s): Patel, Rajnikant B.
• Application Number:
  US10/295,633
• Publication Number:
  US 20040095020A1
• Time in Patent Office: 733 Days
• Field of Search: 307/31, 307/35, 307/39, 307/125, 307/127, 307/40, 307/151, 307/51, 307/87, 323/222, 323/225, 323/267, 323/258, 363/41, 363/98.95, 361/683, 700/286, 700/295, 700/22, 700/296
• US Class Current: 307/35
• CPC Class Codes: G05F 3/262 using field-effect transistors only
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02M 1/0012 Control circuits using digital or numerical techniques in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/008 Plural converter units for generating at two or more independent and non-parallel outputs, e.g. systems with plural point of load switching regulators
• CPC Class Codes: H02M 1/0845 digitally controlled (or with digital control)
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/157 with digital control
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: H03M 5/08 Code representation by pulse width
• CPC Class Codes: H05B 41/2828 using control circuits for the switching elements H05B41/2827 takes precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• 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 switching power converter controller controls a plurality of switching power converters which provide power to a host microprocessor. A watchdog timer in the switching power converter controller counts down a timer unless it receives reset signals from the host microprocessor and the watchdog timer issues an interrupt to the microprocessor if the watchdog timer expires. The microprocessor in the switching power converter controller provides a reset command to the host microprocessor in response to receipt of the interrupt. If the host microprocessor does not respond to the reset command, the microprocessor causes the switching power supply controller to power down the power converters.

Claims

1. A switching power converter controller, wherein the switching power converter controller controls a plurality of switching power converters providing power to a host microprocessor, comprising:

a watchdog timer configured to countdown a timer unless it receives reset signals from the host microprocessor; and

a microprocessor;

wherein the watchdog timer is configured to issue an interrupt to the microprocessor if the watchdog timer expires, and wherein the microprocessor is configured to provide a reset command to the host microprocessor in response to the interrupt received from the watchdog timer, and wherein the microprocessor is further configured to cause the switching power supply controller to power down the plurality of power converters if the host microprocessor does not respond to the reset command.

2. The switching power converter controller of claim 1, wherein the microprocessor includes a timer for determining that the host microprocessor does not respond to the reset command.

3. The switching power converter controller of claim 1, wherein the microprocessor is configured to cause the power down of the plurality of switching power converters in a predetermined sequence.

4. The switching power converter controller of claim 3, wherein the microprocessor is configured to cause the power up of the plurality of switching power converters subsequent to the power down sequence.

5. The switching power converter controller of claim 4, wherein the microprocessor is configured to cause the power up of the plurality of switching power converters in a predetermined sequence.