| 摘要 |
<p>PURPOSE:To control a Vpp pulse externally at the time of test or checking an operation margin by providing two MOS transistors (TRs) connecting a pad to a high-voltage generation circuit and giving complementary functions between its cross point and the pad and to circuits. CONSTITUTION:The pad 16 connected to apply a voltage externally is provided between a reference voltage source 1 and a RC circuit 3 and its cross point is used as a node B. Further, a 1st MOS TR 17 provided between the node B and the pad 16 and the 2nd MOD TR 18 provided between the node B and the reference voltage source 1 and functioning complementarily with the MOS TR 17 are provided. When the Vpp pulse is externally desired to control at the test, an H level signal is inputted to a gate of the MOS TR 17 and a L level signal is inputted to a gate of the MOS TR 18. Thus, the voltage inputted to a comparator 5 is a voltage fed to the pad 16 and the Vpp pulse voltage is a value obtained by dividing the voltage fed to the pad 16 by the voltage division ratio of a voltage divider 8.</p> |
