Patent ID: 6229379
Filing Date: 2001-05-08
Classification: H02M

Abstract:
A negative voltage generating circuit comprising:a reference voltage generating circuit for generating a first reference voltage;a voltage dividing circuit for dividing a voltage between said first reference voltage and a negative voltage to produce a division voltage;a comparing circuit for comparing a second reference voltage and said division voltage; anda negative voltage generating section for generating said negative voltage based on the comparing result by said comparing circuit to supply to said voltage dividing circuit,wherein said voltage dividing circuit and said comparing circuit are arranged to be adjacent to each other,wherein a ground pattern of said reference voltage generating circuit and a ground pattern of said comparing circuit are connected to a common ground potential pad,wherein said voltage dividing circuit includes a first resistor section connected to said first reference voltage and a second resistor section connected to said first resistor section and said negative voltage,wherein said first and second resistor sections are formed as first and second diffusion layers in a first well of a first conductive type which is formed in a second well having a second conductive type different from said first conductive type, said second well being formed in a semiconductor region of said first conductive type, andwherein said first diffusion layer is connected to said first reference voltage at a first end, a second end of said first diffusion layer and a first end of said second diffusion layer are connected to output said division voltage, a second end of said second diffusion layer is connected to said negative voltage, and said first well is connected to said negative voltage, and said second well is connected to a positive power supply voltage.