STBC03 Datasheet, PDF (19/34 Pages) STMicroelectronics – Li-Ion linear battery charger with LDO and load switches

STBC03
6.5
6.6
6.7
BATSNS, BATSNSFV
Functional pin description
Battery voltage sense pin. The BATSNS pin must be connected as close as possible to the
battery positive terminal to ensure the maximum accuracy on the floating voltage and on
the battery voltage protection thresholds. The BATSNSFV pin can be used to fix the VFLOAT
value by connecting a proper external series resistor to BATSNSFV. The battery floating
voltage can be set up to 4.45 V according to the following equation:
Equation 2:
𝑉𝑓𝑙𝑜𝑎𝑡_{𝑎𝑑𝑗}
=
𝑉𝑓𝑙𝑜𝑎𝑡_{𝑑𝑒𝑓}
∗
(1
+
𝑅_{𝑓𝑙𝑜𝑎𝑡}
1𝑀Ω
)
𝑉
=
4.2
∗
(1
+
𝑅_{𝑓𝑙𝑜𝑎𝑡}
1𝑀Ω
)
𝑉
Example: to set the battery floating voltage for 4.35 V, refer to the following equation.
Equation 3:
𝑅_{𝑒𝑥𝑡}
=
1𝑀Ω
∗
(𝑉𝑓4í µí±™í µ.í±œ2í µí±Ží µí µí±‰í±¡^{𝑎𝑑𝑗}
−
1)
=
1𝑀Ω
∗
4.35𝑉
( _{4.2𝑉}
−
1)
=
35.7𝐾Ω
If the BATSNSFV pin is connected to the battery positive terminal, the floating voltage is
set for its 4.2 V default value.
BAT
External battery connection pin (positive terminal). A 4.7 µF ceramic bypass capacitor must
be connected to GND.
IN
5 V input supply voltage pin. The STBC03 is powered off from this pin when a valid voltage
source is detected, meaning a voltage higher than VUVLO and lower than VINOVP. A 10 µF
ceramic bypass capacitor must be connected to GND.
DocID029927 Rev 2
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