Srikanth Kotagiri

Keep the Realtime Clock running on the iMX53QSB withouth the +5V Wall supply

Discussion created by Srikanth Kotagiri on Sep 22, 2011
Latest reply on Oct 8, 2013 by Martin Ernst



   I am trying to preserve the date/time values in android when I remove the 5V Wall power supply. The imx53 Hardware reference( IMX53QSBRM) states in Section 3.20


" On the Quick Start board, there are two through-holes (JP1 and JP2) next to the power connector. These through-holes are positioned to hold a Lithium coin cell battery (Sanyo ML1220-VM1 or equivalent). For proper operation, the coin cell posts should be soldered direction to the Quick Start board, with the positive terminal connected to JP1 and the negative terminal connected to JP2. The DA9053 PMIC will charge the coin cell when 5V Wall Power is available. When 5V Wall Power is removed, the coin cell will provide power only to the RTC power rail (VLDO1) supplying power to the i.MX53 processor. The length of time a coin cell can power the RTC subsystem may vary" 


  I have tried it but the date/time settings are lost when the power is removed for more than 5 seconds. Dis anyone else try this?