Circuit arrangement comprising a monitoring device

Patent metadata

Field	Value
Publication number	US-9566920-B2
Application number	US-201113979248-A
Country	US
Kind code	B2
Filing date	Dec 22, 2011
Priority date	Jan 21, 2011
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

A circuit arrangement and a method are provided to avoid an uncontrolled discharge of the battery of a motor vehicle in the event of a defective initialization of an electronic control unit in the motor vehicle. The initialization process is monitored, and the result thereof controls a supply voltage which is fed via a voltage-monitoring line to a monitoring device of a bus-transceiver only when a successful initialization is detected, or the feeding or the generation of the supply voltage is interrupted when successful initialization is not detected. If the monitoring device does not detect the required supply voltage, e.g. at an appropriate time, then it cuts off power to the supply voltage unit that generates the supply voltage.

First claim

The invention claimed is:

1. A circuit arrangement for a motor vehicle,
wherein the motor vehicle has a signal bus adapted to carry an activation signal, and an external voltage source, and
wherein said circuit arrangement comprises:
an external input voltage terminal adapted to be connected to the external voltage source;
a signal bus terminal adapted to be connected to the signal bus;
a bus transceiver that includes a voltage monitoring device, wherein said bus transceiver is connected to said external input voltage terminal and to said signal bus terminal and is adapted to receive the activation signal from the signal bus via said signal bus terminal;
a controllable voltage supply arrangement that includes a controlled voltage output connected to a first monitoring input of said voltage monitoring device, a first voltage node and optionally an optional second voltage node, a supply voltage unit connected and adapted to supply a first voltage to said controlled voltage output via said first voltage node and optionally to supply an optional second voltage to said second voltage node if present, and a voltage control device that is connected to said first voltage node and to said controlled voltage output and that is adapted to control said first voltage supplied by said supply voltage unit via said first voltage node to said controlled voltage output;
a first switch that is connected between said external input voltage terminal and said supply voltage unit, and that has a first switch control input thereof connected to a control output of said bus transceiver; and
a control arrangement that includes a microcontroller, wherein said control arrangement is connected by a voltage supply line to said first voltage node or to said second voltage node and is connected by a control line to a control input of said voltage control device;
wherein said microcontroller is adapted to execute an initialization process, and said control arrangement is adapted to control said voltage control device via said control line responsive to and dependent on a status of said initialization process as indicated by a status signal of said microcontroller.

2. The circuit arrangement according to claim 1 , wherein said bus transceiver is adapted to control said first switch, via said control output and said first switch control input, responsive to and dependent on a voltage condition monitored by said voltage monitoring device at said first monitoring input of said voltage monitoring device.

3. The circuit arrangement according to claim 1 , wherein said first voltage node is connected by said voltage supply line to said control arrangement.

4. The circuit arrangement according to claim 1 , wherein said controllable voltage supply arrangement includes said second voltage node, said supply voltage unit is connected and adapted to supply said second voltage to said second voltage node, and said second voltage node is connected by said voltage supply line to said control arrangement.

5. The circuit arrangement according to claim 1 , wherein said controllable voltage supply arrangement includes said second voltage node, said supply voltage unit is connected and adapted to supply said second voltage to said second voltage node, said voltage monitoring device further has a second monitoring input, and said second voltage node is connected to said second monitoring input.

6. The circuit arrangement according to claim 5 , wherein said first voltage node is not connected to said control arrangement.

7. The circuit arrangement according to claim 1 , wherein said controllable voltage supply arrangement does not include said optional second voltage node, and said supply voltage unit is not adapted to supply said optional second voltage.

8. The circuit arrangement according to claim 2 , wherein said voltage control device is a second switch interposed and connected between said first voltage node and said controlled voltage output.

9. The circuit arrangement according to claim 1 , wherein said voltage control device is arranged and adapted to control said supply voltage unit with respect to supplying said first voltage to said first voltage node.

10. The circuit arrangement according to claim 9 , wherein said voltage control device is incorporated in said supply voltage unit.

11. The circuit arrangement according to claim 9 , wherein said voltage control device comprises a voltage stabilizer that is connected to and controllable by said control arrangement via said control line.

12. The circuit arrangement according to claim 2 , wherein said control arrangement further includes a system monitoring device connected with said microcontroller and connected with said control line, wherein said system monitoring device is adapted to monitor said status of said initialization process as indicated by said status signal, and is adapted to control said voltage control device via said control line responsive to and dependent on said status of said initialization process.

13. The circuit arrangement according to claim 2 , wherein the signal bus is a FlexRay bus, and said first voltage is a VIO voltage supplied at a VIO voltage output of said supply voltage unit connected to said first voltage node.

14. The circuit arrangement according to claim 2 , wherein the signal bus is a CAN bus, and said first voltage is a VCC voltage supplied at a VCC voltage output of said supply voltage unit connected to said first voltage node.

15. A method of operating a circuit arrangement in a motor vehicle, comprising steps:
a) in response to an activation signal provided to a bus transceiver of said circuit arrangement, with said bus transceiver switching on electrical power to a voltage supply arrangement of said circuit arrangement;
b) after said step a), producing at least one voltage with said voltage supply arrangement;
c) supplying from said voltage supply arrangement, to a microcontroller of a control arrangement of said circuit arrangement, a supply voltage among said at least one voltage;
d) after said step c), operating said microcontroller to execute an initialization process;
e) in said control arrangement monitoring a status of said initialization process as indicated by a status signal of said microcontroller;
f) in response to and dependent on said status, selectively applying, to a monitoring input of a voltage monitoring device of said bus transceiver, a monitored voltage among said at least one voltage, wherein said monitored voltage may be the same as or different from said supply voltage;
g) with said voltage monitoring device, monitoring a voltage condition at said monitoring input; and
h) in response to and dependent on said voltage condition monitored with said voltage monitoring device, with said bus transceiver selectively switching off said electrical power to said voltage supply arrangement when said voltage condition fails to satisfy a specified condition.

16. The method according to claim 15 , wherein said step f) comprises applying said monitored voltage to said monitoring input only when said status indicates that said initialization process is successful.

17. The method according to claim 15 , wherein said status indicates that said initialization process is successful when said monitoring in said step e) determines at least one of the following:
a) a predetermined stage of said initialization process is reached,
b) said initialization process is completed, or
c) said initialization process is completed and a watchdog of said circuit arrangement is triggered for a first time.

18. T

Assignees

• Melzl Hubert
• Weber Reinhart
• Haug Harald
• Continental Automotive Gmbh

Inventors

• Melzl Hubert
• Weber Reinhart
• Haug Harald

Classifications

• G06F1/28 Primary

  Supervision thereof, e.g. detecting power-supply failure by out of limits supervision · CPC title

• B60R16/03 Primary

  for supply of electrical power to vehicle subsystems {or for (circuit arrangements for charging batteries H02J7/00)} · CPC title

• G06F11/0751

  Error or fault detection not based on redundancy (power supply failures G06F1/30; network fault management H04L41/06) · CPC title

• G06F11/0739

  in a data processing system embedded in automotive or aircraft systems · CPC title