Sensor device and semiconductor device requiring said sensor device

Abstract

The present invention provides a sensor device that reduces the circuit footprint without compromising the reliability of detection and judgment results, and enables stable state transitions by suppressing fluctuations caused by noise. [Solution] The sensor device 10 is a device that maintains the current pole detection state and outputs an output signal So corresponding to the pole detection state, and includes a binarization circuit 30 that generates a binarization signal S02 indicating whether or not the detection result of the magnetic flux density B is inconsistent with the current pole detection state, a monitoring circuit 40 that outputs a count control signal S05 to continue counting when the inconsistent state has occurred twice in a row, the current time and the time immediately preceding it, a counter 60 that continues or initializes the counting operation in accordance with the count control signal S05 and outputs an output latch signal S08 when the count reaches a set value N, and an output register 90 that switches the signal level of the output signal So by transitioning the current pole detection state in accordance with the output latch signal S08.

Claims

1. A sensor device that maintains the current pole detection state and outputs an output signal corresponding to the current pole detection state, A sensor element that detects magnetic flux density, A binarization circuit that generates a binarization signal indicating whether the detection result of the magnetic flux density by the sensor element is inconsistent with the current pole detection state, A monitoring circuit monitors whether the mismatch state has occurred for a predetermined number of consecutive times based on the binarized signal, and outputs a count control signal according to the monitoring result. A counter that continues or initializes the counting operation in accordance with the count control signal and outputs an output latch signal when the count reaches a set value, The system includes an output register that switches the signal level of the output signal by transitioning the pole detection state in accordance with the output latch signal, The monitoring circuit outputs the count control signal to the counter to continue counting when the mismatched state has occurred at least twice in a row, in the current instance and the one immediately preceding it. A sensor device characterized by the following features.

2. The binarization circuit determines the signal level of the binarized signal based on whether the magnetic flux density exceeds a certain threshold, using a first threshold as a reference when the current pole detection state is a state in which the first pole side is detected, and a second threshold as a reference when the current pole detection state is a state in which the second pole side is detected. The sensor device according to claim 1.

3. The monitoring circuit outputs the count control signal to initialize the counter count if the mismatched state has not occurred twice in a row, in the current instance and the immediately preceding instance. The sensor device according to claim 1 or 2.

4. The aforementioned monitoring circuit is A first flip-flop circuit to which the binarized signal is input, The output of the first flip-flop circuit is input to a second flip-flop circuit, The system includes a logic circuit that outputs the count control signal based on the output of the first flip-flop circuit and the output of the second flip-flop circuit. A sensor device according to any one of claims 1 to 3.

5. The setting value used to determine the count of the counter is 2 to the power of m, where m is a natural number. The system further includes a determination circuit that determines whether the count of the counter has reached the set value and generates the output latch signal. The determination circuit has m input terminals to which the output signals of the m flip-flop circuits constituting the counter are each input, and is composed of an AND circuit that performs an AND operation on the signals supplied to the m input terminals. A sensor device according to any one of claims 1 to 4.

6. The output register toggles in response to a change in the signal level of the output latch signal to a predetermined level, inverting the signal level of the output signal. A sensor device according to any one of claims 1 to 5.

7. A semiconductor device comprising a semiconductor substrate on which a sensor device according to any one of claims 1 to 6 is formed.

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