| 摘要 |
<p>PURPOSE:To use a current mirror type sense amplifier and a precharge type readout circuit by switching and to save power consumption, by connecting them commonly for the readout of data from a ROM cell, and supplying a mode switching signal to switch a fast operation and a slow operation. CONSTITUTION:When a readout enable signal 101 is set at an 'H', a state is set at a readout operation state, and when it is set at an 'L', the state is set in a standby mode and non-operating state. The AND output of the signal 101 and a slow and fast mode switching signal 102 goes to a sense amplifier control signal 104 in the fast operation, and it is inputted to a data readout circuit 109. The AND output of the signal 101, the negative phase of the signal 102, and a pre-charge control clock 103 goes to a sampling control signal in the slow operation, and it is inputted to a ROM cell part 110. The AND output of the signal 101, the negative phase of the control signal 104, and a control signal 105 goes to a pre-charge type readout signal 106, and it is inputted to the data readout circuit 109.</p> |
