Hi all,
As per previous discussions i have changed the crystal with a load capacitance 7pf as per rtc data sheet.
for calculating the Cx1 and Cx2 using the formula
CL=(Cx1*Cx2/(Cx1+Cx2))+Cstray
CL=7pf
Cstray is taken as 4.5pf
the values of Cx1 and Cx2 is getting as 5pf
so i put both cap values of 4.7 pf
the board was kept OFF for 4 days continuously and on 5th day the variation in time was of about 53 sec as compared with std time, and in ON condition for about 48 hours the variation is about 53 sec.
why there is a variation in seconds at ON and OFF conditions??
whether the values of cap selected is correct or not?
please help...
in the data sheet for calibration of the RTC the bit CRSTRIM can be considered as "1" or "0".please explain the difference of setting CRSTRIM bit as "1" and "0"
Thank you in advance..
sara