NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE AND METHOD OF TESTING THE SAME

摘要

Provided is a non-volatile semiconductor storage device which can be downsized with a simple circuit without impairing the function of an error correcting section, and a method of testing the non-volatile semiconductor storage device. An error correction circuit is configured to perform error detection and correction of merely the same number of bits as data bits, and a circuit for performing error detection and correction of check bits is omitted to downsize the circuit. A multiplexer for, in a testing state, replacing a part of the data bits read out from a storage element array with the check bits, and inputting the check bits to the error correction circuit is provided. Thus, error detection and correction of the check bits are performed to enable shipment inspection concerning the check bits as well.

主权项

1. A non-volatile semiconductor storage device, comprising:
a non-volatile semiconductor storage element array for storing data bits and check bits, the non-volatile semiconductor storage element array comprising, as a basic unit, one unit including an m-data-bit storage element and an n-check-bit storage element; an error correction code generating circuit for generating an error correction code based on the data bits and the check bits of the one unit read out from the non-volatile semiconductor storage element array; a control signal generating circuit for outputting a control signal for switching between a first state and a second state; a multiplexer for inputting second state data including at least the check bits and first state data having, of the data bits, the same number of bits as the second state data, and selecting between the first state data and the second state data based on the control signal to output selected one of the first state data and the second state data; and an error correction circuit for performing error correction of merely the same number of bits as the data bits based on data of the data bits excluding the first state data, the selected one of the first state data and the second state data, and the error correction code.