DatasheetsPDF.com

RT9709 Dataheets PDF



Part Number RT9709
Manufacturers RichTek
Logo RichTek
Description Integrated Over Voltage Protection Circuit
Datasheet RT9709 DatasheetRT9709 Datasheet (PDF)

RT9709 Integrated Over Voltage Protection Circuit General Description The RT9709 is an integrated circuit (IC) optimized to protect low voltage system from abnormal high voltage input 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. It also monitors its own temperature and turns the MOSFET off when the chip temperature exceeds 140°C. The RT9709 can supportAC charger or USB charger. When the in.

  RT9709   RT9709



Document
RT9709 Integrated Over Voltage Protection Circuit General Description The RT9709 is an integrated circuit (IC) optimized to protect low voltage system from abnormal high voltage input 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. It also monitors its own temperature and turns the MOSFET off when the chip temperature exceeds 140°C. The RT9709 can supportAC charger or USB charger. When the input voltage exceeds the OVP threshold, the IC turns off the MOSFET within 1us to remove the power before any damage occurs. The current in the 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 has a 4-bit binary counter that accumulates during an OCP event. When the total count reaches 16 times, the MOSFET will be turned off permanently unless the input power is recycled. The IC also monitors the battery voltage VB. When the battery voltage exceeds 4.4V and last for more than 180us the RT9709 will turn off the MOSFET. The internal logic control will turn off and latch the MOSFET when the battery over-voltage event reaches 16 times. Pin Configurations (TOP VIEW) VIN 1 VIN 2 GND 3 WRN 4 NC 5 NC 6 GND 13 12 NC 11 VOUT 10 VOUT 9 ILIM 8 VB 7 EN WDFN-12L 4x3 VIN 1 VIN 2 GND 3 WRN 4 NC 5 GND 11 9 10 VOUT 9 VOUT 8 ILIM 7 VB EN WDFN-10L 3x3 Features z Fully Integrated Protection Circuit for Three Protection Variables ` User Programmable OCP Threshold ` Input OVP Less than 1us ` Battery OVP z Up to 30V Over Voltage Protection z High Accuracy Protection Threshold z High Immunity of False Triggering Under Transients z Warning Indication Output z Enable Input z Thermally Enhanced WDFN Package z RoHS Compliant and Halogen Free Applications z Cellular Phones z Digital Cameras z PDAs and Smart Phones z Portable Instruments Ordering Information RT9709 Note : Package Type QW : WDFN-12L 4x3 (W-Type) QWB : WDFN-10L 3x3 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) OVP Default : 6.8V A : 5.85V B : 6.25V Richtek products are : ` RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. ` Suitable for use in SnPb or Pb-free soldering processes. Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. DS9709-02 April 2011 www.richtek.com 1 RT9709 Typical Application Circuit VIN CIN WRN RT9709/A/B VIN VOUT VIN VOUT GND VB WRN NC ILIM EN Charger RVB + Battery EN RILIMIT Functional Pin Description Pin No. WDFN-12L 4x3 WDFN-10L 3x3 1, 2 1, 2 Pin Name VIN Pin Function Input Power Source Pin. 3 4 5, 6, 12 3 GND Ground Pin. This is an open-drain logic output that turns LOW when any 4 WRN protection event occurs. 5 NC No Internal Connection. 7 6 EN Enable Input Pin. Pull this pin to low or leave it floating to enable the IC. Force this pin to high to disable the IC. Battery Voltage Monitoring Input Pin. This pin is connected to 8 7 VB the battery pack positive terminal via resistor. 9 10, 11 8 9, 10 ILIM VOUT Over-Current Protection Threshold Setting Pin. Connect a resistor between this pin and GND to set the OCP threshold. Output Voltage Pin. Output through the MOSFET. 13 (Expose Pad) 11 (Exposed Pad) GND The exposed pad must be soldered to a large PCB and connected to GND for maximum thermal dissipation. Function Block Diagram VIN VOUT VREF Ibias VDD BASE Driver OCP OCP Seting ILIM INOVP UVLO Control Logic BATOVP Buffer VB EN EN Logic OTP WRN GND www.richtek.com 2 DS9709-02 April 2011 RT9709 Absolute Maximum Ratings (Note 1) z Supply Input Voltage, VIN -------------------------------------------------------------------------------------------- −0.3V to 30V z VOUT, VB --------------------------------------------------------------------------------------------------------------- −0.3V to 7V z Other Pins --------------------------------------------------------------------------------------------------------------- −0.3V to 5.5V z Power Dissipation, PD @ TA = 25°C WDFN-10L 3x3 --------------------------------------------------------------------------------------------------------- 1.429W WDFN-12L 4x3 --------------------------------------------------------------------------------------------------------- 1.667W z Package Thermal Resistance (Note 2) WDFN-10L 3x3, θJA --------------------------------------------------------------------------------------------------- 70°C/W WDFN-10L 3x3, θJC --------------------------------------------------------------------------------------------------- 7°C/W WDFN-12L 4x3, θJA --------------------------------------------------------------------------------------------------- 60°C/W WDFN-12L 4x3, θJC --------------------------------------------------------------------------------------------------.


RT9706 RT9709 RT9712


@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site.
(Privacy Policy & Contact)