STBP120 Datasheet, PDF (9/36 Pages) STMicroelectronics – Overvoltage protection device with thermal shutdown

STBP120
Figure 3. Block diagram
IN
ESD
protection
Core
negative
protection
SUPPLY
REGULATOR
VREF
VCC
VOLTAGE
REFERENCE
Pin descriptions
OSCILLATOR
CHARGE PUMP
MOSFET DRIVER ^OFF
COUNTERS
OUT
Input overvoltage
Input undervoltage
CONTROL LOGIC
Temperature ^{Thermal shutdown}
detector
FLT
MCU
INTERFACE
EN
ESD
ESD
protection protection
GND
AM00306
Figure 4. Typical application circuit^(1),(2)
AC
adapter
SYSTEM
CONNECTOR
OR
POWERED
PERIPHERALS
PERIPHERAL
SUPPLY CURRENT
CHARGING CURRENT
C1 ^IN
OUT
C2
1 µF STBP120 _{1 µF}
DC-DC
EN
CHARGER
IC
BATTERY
PACK
SUPPLY
CIRCUITS
ENABLE
RPU
FLT
EN
GND
RFLT
REN
CONTROLLER
APPLICATION
AM00314a
1. Optional resistors R_EN, R_FLT prevent damage to the controller under extreme voltage or current conditions and are not
required. Low ESR ceramic capacitor C1 is necessary to ensure proper function of the STBP120. Capacitor C2 is not
necessary for STBP120 but may be required by the charger IC.
2. The STBP120 MOSFET switch topology allows the current to also flow in the reverse direction, from OUT to IN, which can
be useful for powering external peripherals from the system connector. The charger IC should not contain the reverse
diode to prevent the battery pack voltage from appearing on the system connector. If the reverse current (supply current) is
undesirable, it may be prevented by connecting a Schottky diode in series with the OUT pin. The voltage drop between IN
and charger is increased by the voltage drop across the diode.
Doc ID 15492 Rev 4
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