主权项 |
1. A high side circuit drive method for transmitting a low potential system input signal to a high potential system, the method comprising:
generating, with a pulse generation circuit, a set signal which is a differential pulse becoming dominant from the rising edge of an input low potential system control signal, and a reset signal, which is a differential pulse becoming dominant from the falling edge of the low potential system control signal; turning on and off, a first level shift circuit including an n-type channel switching element, in accordance with the set signal, and a resistance element being connected in series, and a second level shift circuit configured by an n-type channel switching element, in accordance with the reset signal, wherein a resistance element is connected in series; holding, by a latch circuit, a high side circuit output condition from an output value of the first level shift circuit and an output value of the second level shift circuit; generating, by a driver circuit, a signal driving a high potential side switching element based on an output of the latch circuit; wherein: a latch malfunction protection circuit is configured such that a predetermined condition of the output values of the first and second level shift circuits is not transmitted to a latch input, a logical sum circuit having each of the output values of the first and second level shift circuits as inputs, a first p-type channel semiconductor element, the source terminal of which is connected to a high side circuit high potential side power supply potential and the drain terminal of which is connected to the output of the first level shift circuit, and a second p-type channel semiconductor element, the source terminal of which is connected to the high side circuit high potential side power supply potential and the drain terminal of which is connected to the output of the second level shift circuit, are provided, the output terminal of the logical sum circuit is connected to the gate terminals of the first and second p-type channel semiconductor elements, and the set signal and reset signal of the pulse generator circuit are both put at an H level for a certain period by, when one differential pulse, which is dominant, of the pulse generator circuit is generated, the other differential pulse, the output of which is secondary, being output a certain time after the generation of the dominant differential pulse. |