Switching status determination device and method for determining switching status
AssigneeDenso Corporation
InventorsAtsushi Nakazawa, Nobutomo Takagi
Life of this patent
Estimating the term…
Abstract
A sampling voltage is periodically applied between contacts of a switch of a device to determine a status of the switch. When a CPU is in a sleep state and the status of the switch is determined closed, the CPU is activated. The sampling voltage when the CPU is in the sleep state is adjusted lower than the one when the CPU is in the wakeup state. This reduces power consumption for the switch status determination. The sampling voltage adjusted at the lower level periodically adjusted to a higher level to reduce errors in the determination due to insulation films on the contacts.
Claims10
A switch status determination device comprising:
- a voltage application means that periodically applies a direct current voltage between contacts of a manual switch of a device;
- a determination means that determines a status of the manual switch;
- a voltage adjusting means for adjusting the levels of the direct current voltage applied between the contacts, wherein
- the voltage application means produces at least high and low levels of the direct current voltage for applying between the contacts, and
- the determination means determines the status of the manual switch by detecting a current flowing between the contacts when the direct current voltage is applied and the determined status is used for control of the device having the manual switch, the control is performed by a control device.
A method for determining a switching status of a manual switch of a device, comprising:
- periodically applying a direct current voltage between contacts of the manual switch;
- detecting a current flowing between the contacts;
- determining a status of the manual switch based on the current detection;
- and
- sending a determination result to a control device that controls the device having the manual switch.
Dependencies are inferred from the claim text.