Datasheet 8.0 V to 35V, 1.5A 1ch Buck Converter with Integrated FET BD9870FPS General Description Key Specifications The BD9870FPS is a single-channel step-down Input Voltage Range: 8.0V to 35.0V switching regulator integrated with a P-Channel Output Voltage Range:1.0V to0.8Vx(VCC-IOUTxRON)V MOSFET capable of PWM operation at 900 kHz. It Output Current: 1.5A(Max) employs the use of smaller coil and circuitry to eliminate Switching Frequency: 900kHz(Typ) the need for external compensation. The circuitry Output ON-Resistance: 1.0(Typ) consists only of a diode, coil and ceramic capacitor thus Standby Current: 0A (Typ) reducing the board size significantly. Operating Temperature Range: -40C to +85C Features Package W(Typ) x D(Typ) x H(Max) Built-in P-Channel MOSFET for High Efficiency Adjustable Output Voltage Via External Resistors Soft-Start Time: 5ms (Fixed) Built-In Over-Current Protection and Thermal Shutdown Circuits ON/OFF Control Via STBY Pin Ceramic Output Capacitor Compatibility Applications TVs, Printers, DVD Players, Projectors, Gaming TO252S-5 Devices, PCs, Car Audio/Navigation Systems, ETCs, 6.50mm x 9.50mm x 1.30mm Communication Equipment, AV Products, Office Equipment, Industrial Devices, and more. Typical Application Circuit L1 VIN Vo VCC OUT D C CIN1 1 IN0 CO Figur R 1 e 6. Oscill ST BY INV ator Freq uenc R2 y vs. Suppl y GND Volta ge Figure 1. Typical Application Circuit Product structure Silicon monolithic integrated circuit This product has no designed protection against radioactive rays www.rohm.com . TSZ02201-0Q3Q0AJ00430-1-2 2014 ROHM Co., Ltd. All rights reserved. 1/16 05.Nov.2014 Rev.001 TSZ22111 14 001 STBY INV OUT OUT VCC BD9870FPS Pin Configuration TO252S-5 (TOP VIEW) GND Figure 2. Pin Configuration Pin Description Pin No. Pin Name Function 1 VCC Input power supply pin 2 OUT Internal Pch FET drain pin (Note 1) 3 OUT Internal Pch FET drain pin FIN GND Ground 4 INV Output voltage feedback pin 5 STBY ON/OFF control pin (Note 1) Normally OPEN Block Diagram VCC 1 VREF PW COMP DRIVER M OSC STBY 5 STBY CTL LOGIC 2 OUT OCP TSD Error AMP 4 INV SS GND(FIN) www.rohm.com TSZ02201-0Q3Q0AJ00430-1-2 2014 ROHM Co., Ltd. All rights reserved. 2/16 05.Nov.2014 Rev.001 TSZ22111 15 001