| 摘要 |
<p>PURPOSE:To accurately perform duty conversion without receiving any influence from the waveform of input signals by obtaining pulses of a required duty by comparing charging voltages of two charge circuits the charging and discharging of which are controlled synchronously to the input signals in phase and which have different charging time constants. CONSTITUTION:A 1st capacitor 3 is charged by means of a 1st constant-current circuit constituted of a resistance 1 and transistor 2 and a 2nd capacitor 7 is charged by means of a 2nd constant-current circuit constituted of a resistance 5 and transistor 6. Switches 4 and 8 respectively short-circuit the terminals of the capacitors 3 and 7. A sample-and-hold circuit is constituted of buffers 9 and 12, switch 10, and capacitor 11 and the switches 4, 8, and 10 are turned on and turned off in fixed cycles by means of a sample-and-hold control circuit 14. A comparator 13 compares the output voltage of the buffer 12, namely, the charging voltage of the capacitor 7 with the charging voltage of the capacitor 3 and outputs a converted signal to an output terminal 18.</p> |
