The D21G Proto I received from Mouser does not have a battery installed for the RTC.
1) Is unit suppose to ship with a battery?
2) What battery model is correct? Nothing in datasheet and top board picture shows a CR1220 while schematic has CR1225.
The units ship without the Lithium coin battery; we cannot send any international shipments containing batteries.
The standard battery is CR1220. It might be possible to fit the slightly thicker CR1225 in the holder but we have not tested that.
I tried the CR1225 (I had some in store, and no CR1220 readily available) and I did not dare force them in the holder.
Better stick to the CR1220 or, even better, BR1220 (high temperature version), much more reliable over 35°C, which is frequent in cabinets.
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