RT8063 3A, 2MHz, Synchronous Step-Down Converter General Description Features zz z zz High Efficiency : Up to 95% The RT8063 is a high efficiency synchronous, step-down z Adjustable Frequency : 200kHz to 2MHz DC/DC converter. Its input voltage range is from 2.7V to zz z zz No Schottky Diode Required 5.5V and provides an adjustable regulated output voltage zz z zz 0.8V Reference Allows Low Output Voltage from 0.8V to 5V while delivering up to 3A of output current. zz z zz Low Dropout Operation : 100% Duty Cycle The internal synchronous low on resistance power zz z zz Enable Function switches increase efficiency and eliminate the need for zz z zz Internal Soft-Start an external Schottky diode. The default switching zz z zz RoHS Compliant and Halogen Free frequency is set at 2MHz, if the RT pin is left open. It can also be varied from 200kHz to 2MHz by adding an external Applications resistor. Current mode operation with external z LCD TV and Monitor compensation allows the transient response to be z Notebook Computers optimized over a wide range of loads and output capacitors. z Distributed Power Systems z IP Phones Ordering Information z Digital Cameras RT8063 Package Type Pin Configurations SP : SOP-8 (Exposed Pad-Option 2) (TOP VIEW) Lead Plating System G : Green (Halogen Free and Pb Free) COMP 8 FB Note : 2 7 GND RT GND 3 6 Richtek products are : EN LX 9 4 VIN 5 LX RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. SOP-8 (Exposed Pad) Suitable for use in SnPb or Pb-free soldering processes. Marking Information RT8063GSP : Product Number RT8063 YMDNN : Date Code GSPYMDNN Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS8063-07 November 2012 www.richtek.com 1RT8063 Typical Application Circuit RT8063 L 5, 6 LX V V OUT IN 4 VIN 2.7V to 5.5V R1 C IN 10F 8 FB C OUT 3 R COMP EN 1 COMP R2 C COMP R OSC 2, 7 RT GND 9 (Exposed Pad) Note : Using all Ceramic Capacitors Table 1. Recommended Components Selection for f = 1MHz SW V (V) R1 (k ) R2 (k ) R (k ) C (pF) L (H) C (F) OUT COMP COMP OUT 3.3 75 24 33 560 2 22 2.5 51 24 22 560 2 22 1.8 30 24 15 560 1.5 22 1.5 21 24 13 560 1.5 22 1.2 12 24 11 560 1.5 22 1.0 6 24 8.2 560 1.5 22 Functional Pin Description Pin No. Pin Name Pin Function Error Amplifier Compensation Point. The current comparator threshold increases 1 COMP with this control voltage. Connect external compensation elements to this pin to stabilize the control loop. 2, Ground. The exposed pad must be soldered to a large PCB and connected to GND GND 9 (Exposed Pad) for maximum power dissipation. Enable Control Input. Float or connect this pin to logic high for enable. Connect to 3 EN GND for disable. 4 VIN Power Input Supply. Decouple this pin to GND with a capacitor. Internal Power MOSFET Switches Output. Connect these pins to the inductor 5, 6 LX together. Oscillator Resistor Input. Connecting a resistor from this pin to GND sets the 7 RT switching frequency. If this pin is floating, the frequency will be set at 2MHz internally. Feedback. Receives the feedback voltage from a resistive divider connected across 8 FB the output. Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS8063-07 November 2012 2