2.7V to 5.5V Input ,3A Integrated MOSFET Single Synchronous Buck DC/DC Converter BD9B331GWZ General Description Key Specifications ROHMs high efficiency switching regulator, Input Voltage Range: 2.7V to 5.5V BD9B331GWZ, is a step-down converter designed to Output Voltage Range: 0.6V to PVCC0.8V produce a low voltage output of 0.6V~3.3V from a Output Current: 3.0A (Max) 2.7V~5.5V power supply line. It offers high efficiency in Switching Frequency: 1.3MHz(Typ) all load ranges by automatic PFM/PWM adjustment. It High Side FET ON Resistance: 23m(Typ) employs an On time control system to provide faster Low Side FET ON Resistance: 23m(Typ) transient response to sudden change in load. Standby Current: 0A (Typ) Operating Temperature Range: -40C to +85C Features Fast transient response with On time control system. Package(s) W(Typ) x D(Typ) x H(Max) High efficiency for all load range with synchronous UCSP30L1: 1.98mm x 1.80mm x 0.33mm rectifier (Nch/Nch FET) and adaptive PFM/PWM system. Adjustable Soft-start function. Thermal and UVLO protection. Short-circuit current protection with pulse count Shutdown function. Applications Power supply for LSI including SoC, DSP, Micro computer and ASIC Laptop PC / Tablet PC / Server . LCD TV, Storage Devices (HDD / SSD) Printer Amusement UCSP30L1 Secondary power supply Typical Application Circuit(s) VIN PGD PVCC PGD BST AVCC CIN CBST EN L BD9B331GWZ VOUT SW EN SS FB COUT CSS RES AGND PGND Figure 1. Typical Application Circuit Product structure : Silicon monolithic integrated circuit This product has no designed protection against radioactive rays . www.rohm.com TSZ02201-0J3J0AJ00810-1-2 2015 ROHM Co., Ltd. All rights reserved. 1/27 TSZ22111 14 001 27.MAY.2015 Rev.002 DatasheetDatasheet BD9B331GWZ Pin Configuration (BOTTOM VIEW) D C B A 123 4 Figure 2. Pin Configuration Pin Description(s) Pin No Symbol Function Pin No Symbol Function A1 FB C1 EN Output feedback pin Enable pinHigh active A2 AGND C2 SS Ground pin Soft start capacitor connection pin A3 PGND C3 SW Power ground pin Switch pin A4 PGND Power ground pin C4 SW Switch pin B1 PGD D1 AVCC Power good open drain pin Power supply input pin Reserved pin B2 RES D2 BST Bootstrap pin (Connect to Ground) B3 SW D3 PVCC Switch pin Power supply input pin B4 SW D4 PVCC Switch pin Power supply input pin Block Diagram(s) PVcc AVcc 22uF 1000pF ILIM EN UVLO BST FB 0.1uF Control On Time Modulation Logic 1uH + VOUT Error Amp SW On Time DRV + SS 22uF Over shoot reduction Amp REF PGND TSD 0.8REF 0.85REF PGD RES AGND 100pF Figure 3. Block Diagram www.rohm.com TSZ02201-0J3J0AJ00810-1-2 2015 ROHM Co., Ltd. All rights reserved. 2/27 TSZ22111 15 001 27.MAY.2015 Rev.002