Datasheet 2.7V to 5.5V Input, 3A Integrated MOSFET Single Synchronous Bu ck DC/DC Converter BD9A302QWZ General Description Key Specifications BD9A302QWZ is a synchronous buck DC/DC Input Voltage Range: 2.7V to 5.5V converter with built-in low on-resistance power Output Voltage Range: 0.8V to VIN x 0.7V MOSFETs. This IC is capable of providing current up Output Current: 3A(Max) TM to 3A. The SLLM control provides excellent Switching Frequency: 1MHz(Typ) efficiency characteristics in light-load conditions which High-Side MOSFET ON-Resistance: 50m (Typ) make the product ideal for equipment and devices that Low-Side MOSFET ON-Resistance: 50m (Typ) demand minimal standby power consumption. The Standby Current: 0A (Typ) oscillating frequency is high at 1MHz using a small value of inductor. BD9A302QWZ is a current mode Package W (Typ) x D (Typ) x H (Max) control DC/DC converter and features high-speed UMMP008AZ020 2.00mm x 2.00mm x 0.40mm transient response. Phase compensation can also be set easily. Features Single Synchronous Buck DC/DC Converter TM SLLM (Simple Light Load Mode) Control Over Current Protection Short Circuit Protection Thermal Shutdown Protection Under Voltage Lockout Protection UMMP008AZ020 Package (Backside Heat Dissipation) Applications UMMP008AZ020 Step-Down Power Supply for DSPs, FPGAs, Microprocessors, etc. Laptop PCs / Tablet PCs / Servers LCD TVs Storage Devices (HDDs/SSDs) Printers, OA Equipment Distributed Power Supplies, Secondary Power Supplies Typical Application Circuit BD9A302QWZ VIN VIN BST MODE MODE 0.1F 10F 0.1F VOUT Enable SW EN 1.5H ITH 22F2 R 2 FB R ITH GND C R ITH 1 Figure 1. Application Circuit Product structure : Silicon monolithic integrated circuit This product has no designed protection against radioactive rays www.rohm.com TSZ02201-0F3F0AJ00100-1-2 2017 ROHM Co., Ltd. All rights reserved. 1/36 TSZ22111 14 001 14.Mar.2017 Rev.001 BD9A302QWZ Pin Configuration (TOP VIEW) VIN 1 8 GND E-PAD EN 2 7 FB BST 3 6 ITH SW 4 5 MODE Figure 2. Pin Configuration Pin Descriptions Pin No. Pin Name Function Power supply terminal for the switching regulator and control circuit. 1 VIN Connecting 10F and 0.1F ceramic capacitors are recommended. Enable terminal. Turning this terminal signal Low (0.8V or lower) forces the device to enter the shutdown mode. 2 EN Turning this terminal signal High (2.0V or higher) enables the device. The EN terminal must be properly terminated. Terminal for bootstrap. 3 BST Connect a bootstrap capacitor of 0.1F between this terminal and SW terminal. The voltage of the bootstrap capacitor is the gate drive voltage of the High-Side MOSFET. Switch terminal. The SW terminal is connected to the source of the High-Side MOSFET and drain of the Low-Side MOSFET. Connect a bootstrap capacitor of 0.1F between the SW 4 SW terminal and BST terminal. In addition, connect an inductor of 1.5H considering the direct current superimposition characteristic. Terminal for setting switching control mode. Turning this terminal signal Low (0.2V or lower) forces the device to operate in fixed frequency PWM mode. Turning this terminal signal High 5 MODE (0.8V or higher) enables the SLLM control and the mode is automatically switched between SLLM control and fixed frequency PWM mode. Do not change this terminal voltage during operation. Terminal for the output of the error amplifier and the input of the current comparator. 6 ITH Connect phase compensation components to this terminal. 7 FB Inverting input terminal for the error amplifier. 8 GND Ground terminal for the output stage of the switching regulator and the control circuit. Backside heat dissipation pad. Connecting to the PCB ground plane by using multiple vias - E-PAD provides excellent heat dissipation characteristics. www.rohm.com TSZ02201-0F3F0AJ00100-1-2 2017 ROHM Co., Ltd. All rights reserved. 2/36 TSZ22111 15 001 14.Mar.2017 Rev.001