To provide a rotation number detection system which performs stable rotation number detection for both lower rotation numbers and higher rotation numbers.
The rotation number detection system comprises a pulse counter 12 which derives a predetermined number of continuous pulses, wherein the number depends on the rotation number of an object to be detected, a logarithmic convertor 18 to which pulse outputs derived from the pulse counter 12 are inputted and which derives a pulse number of pulse outputs, wherein the pulse number is equivalent to the logarithm of the pulse number of the pulse outputs, and a D/A convertor 19 which converts pulse outputs derived from the logarithmic convertor 18 from a digital signal to an analog signal. An output by the D/A convertor 19 is derives as a rotation number signal.
| JPS59226866 | ARITHMETIC UNIT OF SAFE INTER-CAR DISTANCE |
| JP2003534628 | [Title of Invention] Lighting device |
| JPH09325051 | DISPLAY DEVICE |
Masuo Oiwa
Toshihide Kodama
Keigo Murakami
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