Datasheet

DocID023755 Rev 4 19/31
STC3115 Functional description
31
Figure 11. BATD and RSTIO
The BATD/CD pin used as a battery detector is an analog I/O.The input detection threshold
is typically 1.61V.
BATD/CD is also an output connected to V
CC
level when active. Otherwise, it is high
impedance.
The RSTIO/BATD signal is used to control the application system reset during the initial
OCV measurement. The RSTIO/BATD pin is a standard I/O pin with open drain output.
BATD/CD can be connected to the NTC sensor or to the identification resistor of the battery
pack. The STC3115 does not provide any biasing voltage or current for the battery
detection. An external pull-up resistor or another device has to pull the BATD/CD pin high
when the battery is removed.
Figure 12. BATD/CD pin connection when used as battery detector
BATD/CD
RSTIO/BATD
VCC
BATD_drive_high
BATD_comp_out
RSTI
RSTO
1.61 V
+
-
STC3115 STC3115
Other biasing
and/or detection
circuit
Battery
pack
BATD/CD
Rid
BATD biasing by external circuitryBATD resistor biasing
Battery pack
Rid
Ru
(>1 M)
1K
1K
BATD/CD