The Total Level-leakage Protection Chip Full-custom Design

Most of the general leakage current protector chips today are poor in control precision and are subject to the interference mistaking action frequently. In this paper a new type of multifunctional general leakage current protector chip is presented, .some features of this chip are listed below:(1) The validity of the input signal is discriminated. The chip use digital control circuit to check the width , the continuity and the duration of the input pulse, making the chip out of mistaking actions caused by interference.(2) The chip use the digital circuit to realize the time control replacing the RC circuit, which can be more accurate. In this way, the matching precision among different protection levels can greatly improved, the numbers of peripheral discrete devices can be reduced.(3) The chip can be programmable to suit different application conditions through two programmable pins. It can also provides convenience to the matching among different protection levels.(4) The switch is controlled smartly. The chip can judge the stability of the electric net, and decide the switch to be off or on.(5) The chip has the function of warning. If something unexpected happens, the chip will warn the people to avoid the damage.(6) The chip has the advantage of low power dissipation by using the CMOS digital circuit. The total power dissipation is only 1.5mW.(7) The chip has the advantage of low cost because of small area designed by the full-custom approach. The area of the final product chip is only 2mm~2.The chip is a mixed-signal chip, it joined the MPW plan launched by ICC, it was taped out in Shanghua Semiconductor Corp., Wuxi. It was processed in 5V 0.6um CMOS process(twin well, double metal, double polysilicon). The test chip area is 4mm~2 with 28 test pins.