Daddy J
Newbie level 1
I want to output a square wave of 180 Khz.
what is the simplest way to achieve this?
Please use layman language as I am not trained in this.
I found this on My question is;
is this capable of 180 Khz and hohw do I establish this output?
The following is pasted from the .pdf.
11 Crystal Controlled Oscillator
A simple yet very stable oscillator can be obtained by using a quartz crystal resonator as the feedback
element. Figure 15 gives a typical circuit diagram of this. This value of R 1
and R 2
are equal so that the
comparator will switch symmetrically about +V CC /2. The RC time constant of R 3
and C 1
is set to be several
times greater than the period of the oscillating frequency, insuring a 50% duty cycle by maintaining a DC
voltage at the inverting input equal to the absolute average of the output waveform.
14 AN-74 LM139/LM239/LM339 A Quad of Independently Functioning SNOA654–May 2004
Comparators Submit Documentation Feedback
Copyright © 2004, Texas Instruments Incorporated
www.ti.com MOS Clock Driver
Figure 15. Crystal Controlled Oscillator
When specifying the crystal, be sure to order series resonant along with the desired temperature
coefficient and load capacitance to be used.
what is the simplest way to achieve this?
Please use layman language as I am not trained in this.
I found this on My question is;
is this capable of 180 Khz and hohw do I establish this output?
The following is pasted from the .pdf.
11 Crystal Controlled Oscillator
A simple yet very stable oscillator can be obtained by using a quartz crystal resonator as the feedback
element. Figure 15 gives a typical circuit diagram of this. This value of R 1
and R 2
are equal so that the
comparator will switch symmetrically about +V CC /2. The RC time constant of R 3
and C 1
is set to be several
times greater than the period of the oscillating frequency, insuring a 50% duty cycle by maintaining a DC
voltage at the inverting input equal to the absolute average of the output waveform.
14 AN-74 LM139/LM239/LM339 A Quad of Independently Functioning SNOA654–May 2004
Comparators Submit Documentation Feedback
Copyright © 2004, Texas Instruments Incorporated
www.ti.com MOS Clock Driver
Figure 15. Crystal Controlled Oscillator
When specifying the crystal, be sure to order series resonant along with the desired temperature
coefficient and load capacitance to be used.