Hi,I am using this chip Cdcs502 from Ti.I am running a 27Mhz crystal and connecting Capacitor load of 35pF ,with FS=0,the output is a clock pulse with 0.8 low and 2.1 high,i think this is fine.But the problem is when i do FS=1,the frequency gets 108Mhz but the amplitude becomes very low , the peak to peak amplitube is 800mV having a DC offset of 1.6 V...Kindly help me with this..]I need this 108Mhz signal to clock my EPM7064S. Kindly help!!
According to the datasheet, CDCS502 has 32 ohm driver impedance. It should be able to drive regular capacitive loads. However I don't have the chip and check it's behaviour.--- Quote Start --- with FS=0,the output is a clock pulse with 0.8 low and 2.1 high,i think this is fine. --- Quote End --- This is far from keeping LVCMOS level specification. Sounds like you connected a heavy resistive load to output, you should operate it basically unloaded.