| abstract |
A malfunction caused by calibration command contention is prevented. A channel CHA including a data output circuit 41A whose output impedance is adjusted according to an adjustment code CODE, a channel CHB including a data output circuit whose output impedance is adjusted according to an adjustment code CODE, and calibration execution An arbitration circuit 200 that arbitrates the signals ZQEXEA and ZQEXEB, and a calibration execution circuit 100 that generates an adjustment code CODE under the control of the arbitration circuit 200 are provided. Even if a calibration command is issued for any channel, a common adjustment code is generated for each channel, so even if calibration commands conflict, the adjustment code is generated correctly. It becomes possible to do. [Selection] Figure 4 |