PROGRAMMABLE REFERENCE VOLTAGE GENERATING CIRCUIT, AND ITS LAYOUT METHOD

摘要

PROBLEM TO BE SOLVED: To provide a reference voltage generating circuit that programmably generates a reference voltage according to an external code and to provide its layout method. SOLUTION: The programmable reference voltage generating circuit is provided with a reference voltage bias part 501 comprising; a 1st diode type transistor 510 connected between a power source voltage VDDQ and an internal reference voltage Vref- in; and a 2nd diode type transistor 512 connected between the internal reference voltage Vref- in and a ground voltage VSSQ, and with a reference voltage bias part 520 that increases or decreases the internal reference voltage Vref- in in response to thermometer codes U[6:0], D[6:0] for converting external binary codes.