Problem with quartz ABS07 oscillator

[sbrana]

in my project I have a pcf8583 connected to quartz abs07 smd I have mounted on board abs07 but the quartz not oscilled ,I have substitued abs07 smd quarz with trough hole quartz and quartz oscille, I don't understand the substituction I can think that it is a problem of capacitor but in the schematic I don' t have capacitor!!!

 

[FvM]

Re: oscillator problem

1. In the PCF8583 datasheet, a 5 - 25 pF trimmer capacitance is specified. I would be primarly necessary for adjusting the frequency but also influences oscillator behaviour. I would try if a capacitor in this place has a positive effect.

2.ABS07 has a Rs,max spec. of 70k but PCF8583 allows for 40 k only. If Rs is actually above 40k, it may be a reason to have no oscillation.