Nec Corporation

Renesas Electronics Corporation

Norihiko Ishizaki

Tatsuya Ishikawa

Yuichi Iwaya

Yoshiaki Daimon

In a system using a device not adapted to a single wire bus, a semiconductor device includes an external terminal to be coupled to a power source terminal of an external device, a port that supplies a power source voltage for the external device to the external terminal, a power manager that controls an output of the port, and a CPU that controls an operation of the power manager.

Semiconductor device and system

In a microcomputer, a high-order address bus of a control processing unit (CPU) is coupled to a first input of an address selector and an address latch having an output coupled to a second input of the address selector. An output of the address selector is connected to one input of a multiplexer having the other input connected to a high-order data bus of the CPU and an output connected to high-order address/data bus terminals. In the case that the microcomputer is coupled to only 8-bit external memories, the high-order address is outputted through the high-order address/data bus terminals during a period of accessing the external memory, and the address latch and the address selector are controlled to output the high-order address latched in the address latch through the high-order address/data bus terminals during a period of executing no access to the external memory.

Growing community of inventors

Tokyo, Japan

Norihiko Ishizaki