RT4803WSC

RT4803 2.5MHz, Synchronous Boost Regulator with Bypass Mode Features General Description 4 Few External Components: 0.47 H Inductor The RT4803 allows systems to take advantage of new and 0603 Case Size Input and Output Capacitors battery chemistries that can supply significant energy Input Voltage Range: 1.8V to 5V when the battery voltage is lower than the required Output Range from 2.85V to 4.4V voltage for system power ICs. By combining built-in VSEL = L 3.3V power transistors, synchronous rectification, and low VSEL = H 3.55V supply current this IC provides a compact solution for Maximum Continuous Load Current: 2A at V > IN systems using advanced Li-Ion battery chemistries. 2.65V Boosting V to 3.35V OUT The RT4803 is a boost regulator designed to provide a Up to 96% Efficient minimum output voltage from a single-cell Li-Ion battery, True Bypass Operation when V > Target V IN OUT even when the battery voltage is below system Internal Synchronous Rectifier minimum. In boost mode, output voltage regulation is Soft-Start with True Load Disconnect guaranteed to a maximum load current of 2A. Forced Bypass Mode Quiescent current in Shutdown Mode is less than 1 A, V Control to Optimize Target V SEL OUT which maximizes battery life. The regulator transitions Short-Circuit Protection smoothly between Bypass and normal Boost Mode. 2 I C Controlled Interface The device can be forced into Bypass Mode to reduce Ultra low Operating Quiescent Current quiescent current. Small WL-CSP 16B Package The RT4803 is available in the WL-CSP-16B 1.67x1.67 Discharge Function (BSC) package. Applications Single-Cell Li-Ion, LiFePO4 Smart-Phones or Tablet 2.5G/3G/4G Mini-Module Data Cards Simplified Application Circuit RT4803 VOUT VIN C IN C OUT + - L1 LX To pull high voltage VSEL EN nBYP PGOOD SDA SCL AGND PGND Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS4803-01 October 2015 www.richtek.com 1 RT4803 Ordering Information Pin Configurations (TOP VIEW) RT4803 Package Type A1 A2 A3 A4 WSC : WL-CSP-16B 1.67x1.67 (BSC) EN PGOOD VIN VIN B1 B2 B3 B4 Note : VSEL SCL VOUT VOUT Richtek products are : C1 C2 C3 C4 nBYP SDA LX LX RoHS compliant and compatible with the current D1 D2 D3 D4 requirements of IPC/JEDEC J-STD-020. AGND PGND PGND PGND Suitable for use in SnPb or Pb-free soldering processes. WL-CSP-16B 1.67x1.67 (BSC) Marking Information 0G : Product Code W : Date Code 0GW Functional Pin Description Pin No. Pin Name Pin Function A1 EN Enable. When this pin is HIGH, the circuit is enabled. Power Good. It is a open-drain output. PGOOD pin pulls low automatically if A2 PGOOD the overload or OTP event occurs. A3, A4 VIN Input Voltage. Connect to Li-Ion battery input power source. Output Voltage Select. When boost is running, this pin can be used to select B1 VSEL output voltage 2 B2 SCL Serial Interface Clock. (Pull down if I C is non-used). B3, B4 VOUT Output Voltage. Place C as close as possible to the device. OUT Bypass. This pin can be used to activate Forced Bypass Mode. When this C1 nBYP pin is LOW, the bypass switches are turned on and the IC is otherwise inactive. 2 C2 SDA Serial Interface Date Line. (Pull down if I C is non-used). C3, C4 LX Switching node. Connect to inductor. Analog Ground. This is the signal ground reference for the IC. All voltage D1 AGND levels are measured with respect to this pin. Power Ground. This is the power return for the IC. The C bypass OUT D2, D3, D4 PGND capacitor should be returned with the shortest path possible to these pins. Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS4803-01 October 2015 2