| 摘要 |
PURPOSE:To perform a leakage test of a cell with ease by having a circuit which controls a holding current and a read current. CONSTITUTION:A holding current applied by wordtops WT 1-1-1-n flows to constant current sources 6-1-6-n for the holding current. The constant current sources 6-1-6-n are controlled in their current values by a controlling signal from a holding current controlling circuit 7. Digit lines DL2-1 and DR3-1 are connected to cells 4-11-4-n1, and also to a digit decoder 5-1. Digit lines DL2-2-2-m and DR3-2-3-m are also connected in the same way. Digit decoders DS5-1-5-m are connected to a constant current source 10 for a read current, and when the digit decoder selected by an address signal is logically turned on, a read current flows on the digit line connected to the selected digit decoder. The constant current source 10 is controlled in its current value by the control signal from a read current control circuit 8. |
