Hello,
Currently I'm trying to design a 4s 18650 charger. For my design I have chosen the LT1513 SEPIC charging IC due to its simplicity. In the manual it has a weird formula for choosing the value of R1 and when I try to use their formula my R1 value isn't even close to what they specify.
If I'm understanding the way the charger works properly I need the following values to program the correct charging voltage.
R1=155k
R2=12.4k
Thus giving me a charging voltage of 16.8v and a reference voltage of 1.245v
I have attached the manual for reference
More about my project:
12v-16.8v battery operating range
Desired charging current 1-1.5A
Using 4 18650 ~3000mah cells in series with a balance board at the battery.
I have not picked a transformer or rectifier so I'm not sure what my input voltage/max current will be. Probably ~25v to get the full potential charging current.
Currently I'm trying to design a 4s 18650 charger. For my design I have chosen the LT1513 SEPIC charging IC due to its simplicity. In the manual it has a weird formula for choosing the value of R1 and when I try to use their formula my R1 value isn't even close to what they specify.
If I'm understanding the way the charger works properly I need the following values to program the correct charging voltage.
R1=155k
R2=12.4k
Thus giving me a charging voltage of 16.8v and a reference voltage of 1.245v
I have attached the manual for reference
More about my project:
12v-16.8v battery operating range
Desired charging current 1-1.5A
Using 4 18650 ~3000mah cells in series with a balance board at the battery.
I have not picked a transformer or rectifier so I'm not sure what my input voltage/max current will be. Probably ~25v to get the full potential charging current.
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