| 摘要 |
PROBLEM TO BE SOLVED: To achieve highly reliable disconnection detection in a semiconductor integrated circuit device having an analog/digital conversion circuit block.SOLUTION: A semiconductor integrated circuit device includes: T type switch circuits TS[k] disposed between input ports A[k] and an input terminal Ain of an analog/digital conversion circuit ADC, each including PMOS transistors MP1, MP2 and MPc and NMOS transistors MN1, MN2 and MNc; and a PMOS transistor MPu for pre-charging Ain to a power supply voltage VCCA. In the case of detecting the presence/absence of a disconnection from the A[k] to signal input terminals Vint[k], firstly the Ain is pre-charged via the MPu to the VCCA, and the MN2 and the MP2 are driven to be ON, and the MN1, MP1, MPc and MNc are driven to be OFF, and secondly the MPu is controlled to be OFF, and the MN1, MN2, MP1 and MP2 are controlled to be ON, and the MPc and the MNc are controlled to be OFF. |
