The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 2005
Filed:
May. 09, 2002
Nobuya Uda, Hyogo, JP;
Nobuya Uda, Hyogo, JP;
Renesas Technology Corp., Tokyo, JP;
Mitsubishi Electric System LSI Design Corporation, Itami, JP;
Abstract
An input circuit of a one-chip microcomputer is connected to an external switching circuit. When an analog input signal of a significant level generated in the external switching circuit is received at an analog input terminal of the input circuit, an A/D conversion start request signal is generated in an A/D conversion start request generating circuit and is sent to an A/D converter. The operation of the A/D converter is started in response to the A/D conversion start request signal, the analog input signal received at the analog input terminal is converted into digital data, and an A/D conversion finish signal is sent from the A/D converter to a CPU of the one-chip microcomputer. The operation of the CPU is started in response to the A/D conversion finish signal, and the digital data is readout to the CPU. Therefore, the A/D converter, the CPU or a clock is not operated to wait for an analog input signal generated in the external switching circuit, but the A/D converter is operated for the A/D conversion, and the CPU is operated to read out the digital data. Accordingly, an electric power consumed in the A/D converter, the CPU and the clock can be reduced.