| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an infrared receiving circuit easy to realize a small size of body at a low manufacturing/ maintenance cost without requiring a complex control system. <P>SOLUTION: The infrared receiving circuit includes a lag lead filter circuit for adjusting a gain for an amplifier by two stages, such as a first gain for an input signal at low frequency and a second gain for an input signal at high frequency. Thus, even if the peak to peak value changes in two stages according to the frequency, the peak to peak value of the output signal can be controlled to almost the same value, regardless of the frequency of the signal. In this case, a lag lead filter circuit is used, so a switch or an input terminal of a switching signal for changing the gain, an additional power supply for an amplifier, and a control system for switching become unnecessary. <P>COPYRIGHT: (C)2004,JPO |
