Facebook
Google
GitHub
Linkedin
Hi to all,
I have a similar problem.
In my case I have a 0.1uF 0603 X7R capacitor in parallel with the CR1220 battery, that powers the backup pin of a DS3231 RTC.
The DS3231 consumes from this battery, when the main power supply is not present, of the order of 100 nA.
In some equipment we have detected that the battery has discharged prematurely.
If in these devices we remove the battery, and measure the consumption of the RTC + capacitor assembly, we see a consumption of between 2.3 and 0.142 mA, which confirms that the battery has discharged prematurely.
If we unsolder the DS3231, we see that the battery's power consumption remains high. But if we unsolder the 0.1uF capacitor, the power consumption disappears. So it seems that the power consumption is caused by this capacitor.
If we check the capacity of the removed capacitor, it is correct.
Interestingly, if we replace the same capacitor we removed earlier, the current remains at 0, and therefore, the battery drain issue is no longer present.
From what I have read here and in other articles, It could be a problem of:
1- Mechanical stresses in the process of de-penalizing the equipment,
2- Or ESD:
"After an electrostatic discharge (ESD) event, a ceramic SMD capacitor might exhibit increased DC leakage current due to internal damage like cracks in the ceramic dielectric. This can lead to a reduction in insulation resistance and a subsequent increase in leakage"
https://incompliancemag.com/effectiveness-of-multilayer-ceramic-capacitors-for-electrostatic-discharge-protection/#:~:text=A simple technique to deal,in the electronic circuit industry.
A ceramic capacitor exhibiting high leakage current after being exposed to ESD (Electrostatic Discharge) can, in some cases, recover or at least reduce the leakage current after being desoldered. This is because ESD can damage the capacitor's internal structure, creating paths for leakage current. However, desoldering and potentially cleaning the capacitor may remove some of the damage or allow the capacitor to self-heal.
https://nepp.nasa.gov/files/16346/08_002_01 GSFC Teverovsky.pdf
The thing is, I'm researching this, and any help you can provide would be appreciated.
Thanks.
Mod: link to old thread.
https://forum.allaboutcircuits.com/...-of-device-installation-2.199813/post-1897201
I have a similar problem.
In my case I have a 0.1uF 0603 X7R capacitor in parallel with the CR1220 battery, that powers the backup pin of a DS3231 RTC.
The DS3231 consumes from this battery, when the main power supply is not present, of the order of 100 nA.
In some equipment we have detected that the battery has discharged prematurely.
If in these devices we remove the battery, and measure the consumption of the RTC + capacitor assembly, we see a consumption of between 2.3 and 0.142 mA, which confirms that the battery has discharged prematurely.
If we unsolder the DS3231, we see that the battery's power consumption remains high. But if we unsolder the 0.1uF capacitor, the power consumption disappears. So it seems that the power consumption is caused by this capacitor.
If we check the capacity of the removed capacitor, it is correct.
Interestingly, if we replace the same capacitor we removed earlier, the current remains at 0, and therefore, the battery drain issue is no longer present.
From what I have read here and in other articles, It could be a problem of:
1- Mechanical stresses in the process of de-penalizing the equipment,
2- Or ESD:
"After an electrostatic discharge (ESD) event, a ceramic SMD capacitor might exhibit increased DC leakage current due to internal damage like cracks in the ceramic dielectric. This can lead to a reduction in insulation resistance and a subsequent increase in leakage"
https://incompliancemag.com/effectiveness-of-multilayer-ceramic-capacitors-for-electrostatic-discharge-protection/#:~:text=A simple technique to deal,in the electronic circuit industry.
A ceramic capacitor exhibiting high leakage current after being exposed to ESD (Electrostatic Discharge) can, in some cases, recover or at least reduce the leakage current after being desoldered. This is because ESD can damage the capacitor's internal structure, creating paths for leakage current. However, desoldering and potentially cleaning the capacitor may remove some of the damage or allow the capacitor to self-heal.
https://nepp.nasa.gov/files/16346/08_002_01 GSFC Teverovsky.pdf
The thing is, I'm researching this, and any help you can provide would be appreciated.
Thanks.
Mod: link to old thread.
https://forum.allaboutcircuits.com/...-of-device-installation-2.199813/post-1897201
Last edited by a moderator:
