| 摘要 |
<p>PURPOSE: To improve reliability at a low power supply voltage and to reduce power consumption by supplying well bias to the well of a specified transmission transistor. CONSTITUTION: When a power supply voltage Vcc is supplied, a supply circuit 32 is driven through an oscillation circuit 34 for the well bias. In such a manner, the well voltage of the transmission transistors TR 28 and 30 is generated. Thus, this voltage boosting circuit is stably operated. When signals VCCH are enabled, the oscillation circuit 20 for a boosted voltage is operated, a Vpp main pump circuit 22 is driven and the boosted voltage Vpp is generated and transmitted to a boosting node 36 through the channel of the TRs 28 and 30 to be conducted/non-conducted corresponding to the control of CVSL circuits 24 and 26. The boosted voltage Vpp from the circuit 22 is transmitted to the node 36 without a voltage drop. The voltage Vpp is supplied to the internal circuit of a memory unit, and in the case that the voltage Vpp becomes lower than a prescribed level, a similar operation is repeated and a fixed boosted voltage Vpp is supplied. In such a manner, the power consumption is reduced.</p> |
