| 摘要 |
PURPOSE: A pumping voltage control circuit is provided to improve back-bias voltage level instability or coupling with VPP voltage as forming a discharge path of the back-bias voltage. CONSTITUTION: A voltage distributor comprises a plurality of resistances(R1~R4) connected between pumping voltage(VPP) and ground power(VSS). The voltage distributor applies voltage of a predetermined level, voltage-divided through the resistance, to a PMOS transistor(P1) if pumping voltage is in a stable state. A discharge control voltage controller determines control voltage of a pumping voltage discharge unit by using the voltage distributed from the voltage distributor. The discharge control voltage controller comprises the PMOS transistor and an NMOS transistor(N2) connected between external power(VDD) and the ground power. The pumping voltage discharge unit includes an NMOS transistor(N1). A pumping voltage level sensor controls a pumping operation of a pumping unit(30). |
