RT9746WSC Richtek

RT9746 VBUS OVP with a PTVS Diode General Description Features PTVS Diode Embedded for VBUS Surge Protection The RT9746 is an overvoltage protection devices feature a Warning Indicator for OVP or UVP low 35m (typ) RON internal FET with PTVS diode. The 28V Maximum Rating for DC Adapter PTVS also protects the devices from surges up to 100V. Integrated Over-Voltage and Over Current When the input voltage exceeds the overvoltage threshold, Protection FET on VBUS for Fault Isolation the internal FET is turned off to prevent damage to the protected down stream components. Applications The internal Over Voltage Thresholds (OVP) are preset to Cellular Phone 6.8V typical. The RT9746 also feature an over-current Smart Handheld Device protection and up to 4.5A. The RT9746 is offered in a small WL-CSP-12B (BSC) Pin Configurations package provides small PCB area applications. (TOP VIEW) Ordering Information A1 A2 A3 A4 GND GND VOUT VOUT PTVS RT9746 B1 B2 B3 B4 GND WRNB VOUT VIN Package Type PTVS C1 C2 C3 C4 WSC : WL-CSP-12B 1.92x1.27 GND OVPFB VIN VIN PTVS OVP Threshold Option Default : 6.8V WL-CSP-12B 1.92x1.27 (BSC) A : 11.5V B : 14.5V Marking Information C : 6.2V Note : RT9746WSC 3C : Product Code Richtek products are : W : Date Code RoHS compliant and compatible with the current require- 3CW ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Simplified Application Circuit RT9746 Adaptor VIN VOUT Charger C OUT C IN R2 VDDIO OVPFB R3 R1 WRNB Processor GND PTVS GND Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS9746-00 March 2016 www.richtek.com 1RT9746 Functional Pin Description Pin No Pin Name Pin Function A1 GND Common Ground Of Internal Circuits. A2, A3, B2 VOUT Output from VBUS Load-Switch. B1 WRNB Inverse Warning Signal (OCP,OTP, OVP, UVLO) Flag Output (Open-Drain). A4, B4, C4 GND PTVS Common Ground of Power TVS Diode. B3, C2, C3 VIN VBUS from Power Adaptor. C1 OVPFB External OVP Adjustment Setting. (if no used, be surely tied to GND) Function Block Diagram VIN VOUT OCP Pre- Regulator GND PTVS GND Power OTP FET POR UVLO Digital Control External WRNB I/O Buffer & Internal OVP OVP OVPFB SEL Operation The RT9746 is a VBUS OVP protector switch. The OVP function is optimized to protect low voltage system from abnormal high input voltage (up to 28V) in handheld application. RT9746 is also embedded Power-TVS diode (PTVS) on VBUS pin for surge protection. If surge waveform is above 30V, it will be clamped to 30V due to PTVS diode. When plugging in VBUS, the OCP will be soft-start in 8ms in order to reduce in rush current and internal VOUT deglitch time is 16/32/64/128ms which is set by fuse. The OCP after soft-start is up to 4.5A for high current application. Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS9746-00 March 2016 2