Patent ID: 6728148
Filing Date: 2004-04-27
Classification: G11C

Abstract:
A programmed value determining circuit comprising:a programmable element whose resistance is changed depending on whether or not there is a program; a detecting portion including a first circuit and a second circuit, the first circuit including first and second switching elements that operate in response to first and second control signals respectively, the first and second switching elements and the programmable element being connected in series between a first power terminal and a second power terminal such that at least the first switching element is inserted between the first power terminal and an intermediate connection node, and at least the second switching element connected to the programmable element in series is inserted between the intermediate connection node and the second power terminal, and the second circuit converting an electric potential at the intermediate connection node to a logic level and outputting it to an output node; and latch means for latching the electric potential at the intermediate connection node to make the intermediate connection node act as a storage node of a programmed value of the programmable element, wherein during a second period subsequent to a first period after power is turned on, at least the second switching element is turned on, the storage node is connected to the second power terminal via the programmable element, and a state of the storage node is detected by the detecting portion, and during a third period after the second period, both the first and the second switching elements are turned off, and the state of the storage node is held by the latch means.