Control device and method for controlling switches based on a voltage value
A control device includes a first series circuit and a second series circuit. In the first series circuit, a first switch and a first resistor are connected in series to each other. In the second series circuit, a second switch and a second resistor are connected in series to each other. A current detection circuit outputs a voltage value that corresponds to a voltage value between two ends of the first resistor. When an instruction to turn on the first switch and the second switch has been given, a control unit senses any occurrence of a failure in at least one of the first switch, the second switch, the first resistor, and the second resistor, based on the voltage value output by the current detection circuit.
1 . A control device comprising:
a first series circuit that includes a first switch and a first resistor connected in series to each other;
a second series circuit that includes a second switch and a second resistor connected in series to each other, and is connected in parallel to the first series circuit;
an instruction unit configured to give an instruction to turn on the first switch and the second switch;
a voltage output circuit including a variable resistor and a differential amplifier, the differential amplifier connected to the two ends of the first resistor, the variable resistor and the differential amplifier operative to calculate a voltage value that corresponds to a voltage value between the two ends of the first resistor and transmit the voltage value to the instruction unit;
a sensing unit configured to sense, when the instruction unit has given an instruction to turn on the first switch and the second switch, any occurrence of a failure in at least one of the first switch, the second switch, the first resistor, and the second resistor based on the voltage value output by the voltage output circuit; and
wherein the voltage value that is output by the voltage output circuit increases with an increase in the voltage value between the two ends of the first resistor,
if the voltage value output by the voltage output circuit is less than a first threshold, the sensing unit senses that a failure has occurred in at least one of the first switch, the first resistor, and the second resistor, and
if the voltage value output by the voltage output circuit is equal to or greater than a second threshold, the sensing unit senses that a failure has occurred in at least one of the second switch, the first resistor, and the second resistor, and
the first threshold is less than the second threshold.
2 . The control device according to claim 1 , further comprising:
a voltage detection circuit configured to detect a voltage value of a connection node between the first switch and the first resistor,
wherein, when having sensed that a failure has occurred in at least one of the first switch, the first resistor, and the second resistor, the sensing unit senses any occurrence of the failure in the first switch based on the voltage value detected by the voltage detection circuit.
3 . The control device according to claim 2 , further comprising
a second voltage detection circuit configured to detect a voltage value of a connection node between the second switch and the second resistor,
wherein, when having sensed that a failure has occurred in at least one of the second switch, the first resistor, and the second resistor, the sensing unit senses any occurrence of the failure in the second switch based on the voltage value detected by the second voltage detection circuit.
4 . The control device according to claim 2 , wherein an electric current flows through the first switch and the first resistor in this order,
the voltage output circuit includes:
a current output unit configured to draw the electric current from a connection node between the first switch and the first resistor, and output the drawn electric current; and
a current resistor through which the electric current output by the current output unit flows, and
the voltage output circuit outputs a voltage value between two ends of the current resistor.
5 . The control device according to claim 1 , further comprising:
a second voltage detection circuit configured to detect a voltage value of a connection node between the second switch and the second resistor,
wherein, when having sensed that a failure has occurred in at least one of the second switch, the first resistor, and the second resistor, the sensing unit senses any occurrence of the failure in the second switch based on the voltage value detected by the second voltage detection circuit.
6 . The control device according to claim 5 , wherein an electric current flows through the first switch and the first resistor in this order,
the voltage output circuit includes:
a current output unit configured to draw the electric current from a connection node between the first switch and the first resistor, and output the drawn electric current; and
a current resistor through which the electric current output by the current output unit flows, and
the voltage output circuit outputs a voltage value between two ends of the current resistor.
7 . The control device according to claim 1 , wherein an electric current flows through the first switch and the first resistor in this order,
the voltage output circuit includes:
a current output unit configured to draw the electric current from a connection node between the first switch and the first resistor, and output the drawn electric current; and
a current resistor through which the electric current output by the current output unit flows, and
the voltage output circuit outputs a voltage value between two ends of the current resistor.
8 . A control method comprising the steps of:
giving an instruction to turn on a first switch connected in series to a first resistor, and a second switch connected in series to a second resistor;
providing a variable resistor and a differential amplifier, the differential amplifier connected to the two ends of the first resistor, the variable resistor and the differential amplifier operative to calculate a voltage value that corresponds to a voltage value between the two ends of the first resistor; and
sensing, when an instruction to turn on the first switch and the second switch has been given, any occurrence of a failure in at least one of the first switch, the second switch, the first resistor, and the second resistor based on the acquired voltage value,
wherein a first series circuit that includes the first switch and the first resistor is connected in parallel to a second series circuit that includes the second switch and the second resistor, wherein the voltage value increases with an increase in the voltage value between the two ends of the first resistor, wherein if the voltage value is less than a first threshold, sensing that a failure has occurred in at least one of the first switch, the first resistor, and the second resistor, wherein if the voltage value is equal to or greater than a second threshold, sensing that a failure has occurred in at least one of the second switch, the first resistor, and the second resistor, and wherein the first threshold is less than the second threshold.
9 . A computer program product comprising a non-transitory, machine-readable medium storing instructions which, when executed by at least one programmable processor, caused at least one programmable processor to execute the steps of:
giving an instruction to turn on a first switch connected in series to a first resistor, and a second switch connected in series to a second resistor;
processing a voltage value determined by a variable resistor and a differential amplifier, wherein the differential amplifier connected to the two ends of the first resistor, the voltage value corresponding to a voltage value between two ends of the first resistor; and
sensing, when an instruction to turn on the first switch and the second switch has been given, any occurrence of a failure in at least one of the first switch, the second switch, the first resistor, and the second resistor based on the acquired voltage value,
wherein a first series circuit that includes the first switch and the first resistor is connected in parallel to a second series circuit that includes the second switch and the second resistor, wherein the voltage value increases with an increase in the voltage value between the two ends of the first resistor, wherein if the voltage value is less than a first threshold, sensing that a failure has occurred in at least one of the first switch, the first resistor, and the second resistor, wherein if the voltage value is equal to or greater than a second threshold, sensing that a failure has occurred in at least one of the second switch, the first resistor, and the second resistor, and wherein the first threshold is less than the second threshold.