Renesas Electronics Corporation

Ntt Docomo, Inc.

Kazuaki Gemma

Tomohiro Akiyama

Kunio Yoshikawa

Tetsuhiro Tanno

Kumiko Yamaguchi

Tetsuhiro Sasagawa

Norihisa Yamamoto

Daisuke Wakasa

Satoshi Akita

A semiconductor device includes clock adjustment circuits, provided to a plurality of functional circuits operating in synchronization with a clock signal respectively for adjusting a delay amount for each functional circuit, and a clock path selection circuit for controlling whether a clock is transmitted to the functional circuits through any one of a plurality of paths included in the clock adjustment circuits respectively. In the semiconductor device, the clock path selection circuit outputs a path instruction signal for instructing switching of a path for transmitting a clock signal in accordance with a change in an operation state of a plurality of functional circuits.

Semiconductor device

A semiconductor device selects one start sequence of the normal start and the low-power-consumption start based on the determination result of the determination circuit. According to the configuration, the operation in the start sequence from the power supply input to the processor operation start can be selected from the operation in which the instantaneous current is suppressed and the high-speed operation based on the supplied power supply.

Semiconductor device and semiconductor system

A semiconductor device has a clock signal generation circuit that generates a clock signal, and a processing circuit that operates in accordance with the clock signal. The semiconductor device can also include an external terminal and a power source terminal that is coupled to the processing circuit. The clock signal generation circuit changes the frequency of the clock signal to be generated in accordance with the voltage value of a current consumption signal supplied to the external terminal. Further, the voltage value of the current consumption signal is changed in accordance with current consumption flowing in the power source terminal. The clock signal generation circuit can change the frequency of the clock signal to be generated in accordance with a value of an analog signal supplied to the external terminal.

Semiconductor device and electronic device

A portable terminal supplies power to a chip card therein with host power off. A power controller supplies power from a battery to a host, the chip card, and a CLF; a first switch opens/closes a power supply channel to the chip card, branching from a power supply channel from the power controller to the host; a second switch opens/closes a power supply channel to the chip card, branching from a power supply channel from the power controller to the CLF; a switch controller opens the first switch and closes the second switch if the CLF detects a contactless RF signal, if the host is off or if the portable terminal is in a low battery mode, and if the contactless RF signal conforms to the communication method of the chip card, and the switch controller closes the first switch and opens the second switch if the host is on.

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Tokyo, Japan

Kazuaki Gemma