DRIVE CIRCUIT
The invention is directed to testing breakdown voltage characteristics of a plurality of output transistors in a batch in a drive circuit instead of measurement using probe needles. A drive circuit includes output transistors made of high breakdown voltage P-channel type MOS transistors, switching control circuits, output terminals, diodes and a control terminal on a semiconductor die. The diodes are made of high breakdown voltage P-channel type MOS transistors in which the source and gate are connected. The anodes of the diodes are connected to the drains of the corresponding output terminals, respectively. The cathodes of the diodes are commonly connected to the control terminal through a wiring.
1 . A drive circuit comprising:
a plurality of output transistors, each of the output transistors comprising a P-channel type MOS transistor comprising a source configured to receive a positive voltage;
a plurality of switching control circuits controlling switching of corresponding output transistors;
a plurality of output terminals, each of the output terminals being connected to a drain of a corresponding output transistor;
a plurality of rectifiers, each of the rectifiers comprising an anode connected to a drain of a corresponding output transistor; and
a control terminal connected to cathodes of the rectifiers.
2 . The drive circuit of claim 1 , wherein each of the rectifiers comprises a P-channel type MOS transistor comprising a source and a gate that are connected.
3 . The drive circuit of claim 1 , wherein a pair of an output transistor and a switching control circuit is disposed under a corresponding output terminal.
4 . The drive circuit of claim 1 , further comprising a voltage application circuit applying a negative voltage to the control terminal in a state where the output transistors are turned off by the switching control circuits.
5 . The drive circuit of claim 1 , further comprising a voltage application circuit initializing voltages of the drains of the output transistors by applying a predetermined voltage to the control terminal.
6 . The drive circuit of claim 1 , further comprising a plurality of vacuum fluorescent displays connected to corresponding output terminals.