I have my Customised MP2759A board.I want to charge 12V lead Acid battery.But my STAT led continuous blink at 2MHz and ACOK led continuous ON with or without Battery connection.my configuration is
Resistor value for CELL to AGND is 60K ( 3 Cell)
Resisor value for VB is pull up using 10K (4.4 V)
Resistor value for VLIM - R1 is 10K and R2 is 220K ( 28V )
Resistor RILIM value is 50K
Resistor RISET value is 50K
at VLIM pin it shows me 1.2V. i checked my battery voltage it is 12V.is there any wrong with my configuration.my led status are not changing with and without battery connection
The MP2759A is specifically meant for charging Li-ion or Li-polymer batteries. These types of chargers typically provide constant current and have Li-ion protections built in like OVP and safety timers.
The MP2759A was not designed to charge acid lead batteries and I would not be able to guarantee its ability to charge or maintain the battery for this type of battery. I believe this is the reason you are seeing faults with this charger.
Lead acid batteries take longer to charge so this is likely why the STAT LED is indicating that the safety timer expiring. They also would require a constant voltage output, while the MP2759A provides constant output voltage in phase 4, the other phases (specifically phase 3 CC) could cause issues.