A high voltage island is formed in the semiconductor substrate for making a high voltage gate drive circuit;
The high voltage junction terminal, the high voltage junction terminal surrounded the high voltage island, the high voltage junction terminal comprises a depletion type MOS device formed around the high voltage island, the depletion type MOS device gate and drain short-circuited, the depletion type MOS device source and high side power supply terminal connected;
The collector and base of the bipolar transistor are shorted and connected with the low side power supply end, and the emitter of the bipolar transistor is connected with the gate of the depletion type MOS device.
Optionally, the high pressure island is quadrilateral, and the depletion MOS device is formed on three adjacent sides of the high pressure island.
Optionally, a high voltage level shift device is formed on the fourth side of the high voltage island.
Optionally, the depletion MOS device comprises:
A first well region having a first conducting type and a second well region having a second conducting type are formed adjacent to each other on the semiconductor substrate;
An active region having a first conductive type formed in the first well region;
A drain having a second conductive type and a third well region are formed in the second well region;
A source pole having a second conductive type formed in the third well region;
An isolation structure formed in the semiconductor substrate between an active region having a first conductive type, a drain having a second conductive type and a source having a second conductive type;
A polysilicon field plate is formed on an isolation structure between a drain having a second conductive type and a source having a second conductive type.
Optionally, the depletion MOS device also includes:
A first buried layer having a first conductive type is formed between the first well region and the semiconductor substrate;
A second buried layer having a second conductive type is formed between the third well region and the semiconductor substrate.
Optionally, the depletion MOS device also includes:
Covering the active region of the first conductive type, the drain having the second conductive type, the source having the second conductive type and the first dielectric layer of the polysilicon field plate;
A contact hole is formed in the first medium layer and filled with a conductive material;
Through the contact hole and the active region having the first conductive type, the drain having the second conductive type, the source region having the second conductive type and the polysilicon field plate connected metal extraction;
Wherein, the drain having a second conductive type and the polysilicon field plate are connected to the same metal outlet.
Optionally, the bipolar transistor is formed in a region in the semiconductor substrate located outside the high voltage junction terminal. According to the integrated circuit chip of the invention, a depletion type MOS device is formed in the high voltage junction terminal inside the chip, which can withstand high voltage, and therefore can be used as a bootstrap device, so that there is no need to use an external bootstrap diode when forming a bootstrap circuit, which improves the integration degree of the chip, simplifies the peripheral circuit, thus reducing the cost and improving the reliability.