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عدد المساهمات : 369 تاريخ التسجيل : 10/01/2010 العمر : 33 الموقع : دورا - الخليل - فلسطين العمل/الترفيه : هندسة كمبيوتر المزاج : جيد
| موضوع: Self-powered Sine to Square wave Converter الجمعة فبراير 19, 2010 12:03 pm | |
| Self-powered Sine to Square wave ConverterConverts sine to square waves without a power-sourceUseful as a test instrument for audio purposes Circuit diagram:Parts:R1_____________1M 1/4W Resistor R2___________100K Linear Potentiometer C1,C2________100µF 25V Electrolytic Capacitors C3____________10nF 63V Polyester Capacitor D1,D2_______1N4148 75V 150mA Diodes IC1___________4069 Hex Inverter IC Device purpose:This circuit is intended to provide good square waves converting a sine wave picked-up from an existing generator. Its main feature consists in the fact that no power-source is needed: thus it can be simply connected between a sine wave generator and the device under test. The input sine wave feeds a voltage doubler formed by C1, C2, D1 & D2 that powers the IC. IC1A amplifies the input sine wave, other inverters included in IC1 squaring the signal and delivering an output square wave of equal mark/space ratio and good rise and fall times through the entire 20Hz-20KHz range. Notes:
- Best performances are obtained with an input sine wave amplitude from 1V RMS onwards.
- Output square wave amplitude is proportional to input amplitude.
- Minimum sine wave input amplitude needed for good performance: 750mV RMS.
- Output square wave amplitude with 1V RMS input: 3V peak to peak, with R2 set at max.
- Minimum output square wave amplitude: 2V peak to peak, with R2 set at max.
- Substituting the two silicon diodes with germanium types (e.g. AA118, AA119), the minimum input threshold can be lowered.
This circuit won £50 and was published on ELECTRONICS WORLD "Circuit Ideas", February 2000 issue, page 135. | |
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