MAX8819A Datasheet, PDF (17/29 Pages) Maxim Integrated Products – PMIC with Integrated Chargers and Smart Power Selector in a 4mm x 4mm TQFN

PMIC with Integrated Chargers and Smart
Power Selector in a 4mm x 4mm TQFN
PREQUALIFICATION
V_BATREG
FAST-CHARGE
(CONSTANT CURRENT)
FAST-CHARGE
(CONSTANT VOLTAGE)
TOP-OFF
DONE
V_BATPRQ
I_CHGMAX
I_PREQUAL
I_TOPOFF
0
HIGH
IMPEDANCE
LOW
Figure 2. Li+/Li-Poly Charge Profile
Battery Charger
Figure 2 shows the typical Li+/Li-Poly charge profile for
the MAX8819_, and Figure 3 shows the battery charger
state diagram.
With a valid DC input that is not suspended, the battery
charger initiates a charge cycle once CEN is driven
high. It first detects the battery voltage. If the battery
voltage is less than the prequalification threshold
(3.0V), the charger enters prequalification mode and
charges the battery at 10% of the maximum fast-charge
current while deeply discharged. Once the battery volt-
age rises to 3.0V, the charger transitions to fast-charge
mode and applies the maximum charge current. As
charging continues, the battery voltage rises until it
approaches the battery regulation voltage (4.2V typ)
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