RT9718 Datasheet, PDF (1/10 Pages) Richtek Technology Corporation – Over Voltage Protection IC

RT9718
Over Voltage Protection IC
General Description
The RT9718 is an integrated circuit optimized to protect
low voltage system from abnormal high input voltage (up
to 28V). The IC monitors the input voltage, battery voltage
and the charging current to make sure all three parameters
are operated in normal range. When the input voltage
exceeds a certain OVP threshold voltage level, the IC will
turn off the power MOSFET within 1μs to remove the power
before any damage occurs. The RT9718 also can provide
a voltage output without the existence of battery.
The current in the power MOSFET is also limited to prevent
charging the battery with an excessive current. The current
limit can be programmed by an external resistor between
ILIM and GND. The OCP function also has a 4-bit binary
counter that accumulates during an OCP event. When the
total count reaches consecutive 16 times, the power
MOSFET is turned off permanently unless the input power
is recycled.
The IC also monitors the battery voltage, Once the battery
voltage exceeds 4.35V and last for more then 180us
blinking time, the RT9718 will turn off the MOSFET. The
internal logic control will turn off the power MOSFET
permanently when the battery over-voltage event occurs
for consecutive 16 times.
Ordering Information
RT9718
Package Type
QW : WDFN-8L 2x2 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)
Note :
OVP
A : 6.80V
B : 5.85V
C : 6.25V
D : 7.20V
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Features
z Fully Integrated Protection Function
` Programmable OCP
` Input OVP
` Battery OVP
z Withstand High Input Voltage Up to 28V
z Over Voltage Turn Off Time Less Than 1us
z High Accuracy Protection Thresholds
z Over Temperature Protection
z High Immunity of False Triggering Under Transients
z Warning Indication Output
z Enable Input
z Thermal Enhanced WDFN Package
z RoHS Compliant and Halogen Free
Applications
z Cellular Phones
z Digital Cameras
z PDAs and Smart Phones
z Portable Instruments
Pin Configurations
(TOP VIEW)
VIN 1
GND 2
NC 3
WRN ⁴
8 VOUT
7 ILIM
6 VB
9 _{5 EN}
WDFN-8L 2x2
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
DS9718-02 May 2011
www.richtek.com
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