Easy Crystal Impedance Checker Circuit


Posted on Sep 9, 2012

On occasion, microprocessors/microcomputers and microprocessor crystals just aren`t compatible with each other. Many microprocessor data sheets specify maximum values for a crystal`s equivalent series resistance (Rs) that aren`t met by some crystals advertised for microprocessor/ microcomputer use. As a result, a crystal with an Rs value greater than the maximum specified for the chip might cause problems, such as a balky or even inoperative clock oscillator. To tackle this problem, a suspected crystal can be given a quick check for Rs with a simple test setup that consists of a sweep generator, oscilloscope, and three resistors (see the figure). When the frequency source is brought to the crystal`s frequency, output 2 will maximize.


Easy Crystal Impedance Checker Circuit
Click here to download the full size of the above Circuit.

If it exceeds the amplitude of output 1, the crystal`s Rs value will be less than the Rs reference resistor`s value. If it doesn`t exceed output l`s amplitude, the crystal`s Rs value is too large.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

4 Watt audio Amplifier
Unipolar-to-dual-supply-converter
Antenna Low Power RF & Wireless Connectivity
a more practical capacitor powered
H1277 HIGH SENSITIVITY HALL EFFECT SENSOR IC WITH FG OUTPUT
Temperature Monitor with Alarm
GVI Digital Remote Control
Operational Amplifier Voltage Comparator Circuits
Pressure Measurement from five-channel low-power programmable sensor signal processor AD7714
Making small tube amplifier 01



Top