LV5781

Ordering number : ENA0663A Bi-CMOS IC LV5781 Overview 3A, Point-of-load, Chopper-type Step-down Converter The LV5781 is a 1-channel chopper-type (low-side Schottky diode) step-down switching regulator. It incorporates an 80mΩ (typical) power MOSFET to achieve high-efficiency operation for 3A output currents. The output voltage is set internally to 3.3V. By adding two external resistors, it is possible to set the voltage to any desired setting above 0.85V. Inrush current at startup can be prevented by the soft start function. Using the ON/OFF pins, the converter can be set to standby mode in which the current consumption is 10µA or less. Both the load and the IC are protected by means of the overcurrent and thermal protection functions. The converter uses the HSSOP14 miniature package. Functions • 3A, 1-channel chopper-type, step-down switching regulator • Output voltage: 3.3V • Setting of any output voltage enabled (external resistors required) • High efficiency: 90% at IOUT=1A, VO=3.3V • Miniature package: HSSOP14 • Soft start function • Standby mode • Overcurrent protection • Thermal shutdown • Fixed frequency: 180kHz Applications • LCD TVs • Game machines Any and all SANYO Semiconductor Co.,Ltd. products described or contained herein are, with regard to "standard application", intended for the use as general electronics equipment (home appliances, AV equipment, communication device, office equipment, industrial equipment etc.). The products mentioned herein shall not be intended for use for any "special application" (medical equipment whose purpose is to sustain life, aerospace instrument, nuclear control device, burning appliances, transportation machine, traffic signal system, safety equipment etc.) that shall require extremely high level of reliability and can directly threaten human lives in case of failure or malfunction of the product or may cause harm to human bodies, nor shall they grant any guarantee thereof. If you should intend to use our products for applications outside the standard applications of our customer who is considering such use and/or outside the scope of our intended standard applications, please consult with us prior to the intended use. If there is no consultation or inquiry before the intended use, our customer shall be solely responsible for the use. Specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customer' s products or equipment. To verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customer' s products or equipment. 13107 MS IM 20070112-S00004 No.A0663-1/7 LV5781 Specifications Absolute Maximum Ratings at Ta=25°C Parameter Maximum input voltage Maximum CBOOT pin voltage Maximum SW pin voltage Maximum voltage between CBOOT and SW pins Maximum voltage at FB, SS, and ENABLE pins Junction temperature Allowable power dissipation Operating temperature range Storage temperature range Tj max Pd max Topr Tstg Mounted on a circuit board *1 Vfs max Symbol VIN max VBT max VSW max VBS max Conditions Ratings 6.5 13 6.5 6.5 6.5 125 0.85 -30 to +80 -40 to +125 Unit V V V V V °C W °C °C *1: Mounted on a specified board: 114.3mm×76.1mm×1.6mm, glass epoxy. *2: To ensure that the maximum voltage is not exceeded even for an instant, check that the coil voltage and other surge voltage levels are factored in. Recommended Operating Conditions at Ta=25°C Parameter VIN pin voltage CBOOT pin voltage SW pin voltage FB, SS, and ENABLE pin voltage Symbol VIN VBT VSW VFSO Conditions Ratings 4.5 to 6 0 to 6 6 6 Unit V V V V Electrical Characteristics at Ta=25°C, VIN=5V (Unless specifically specified) Parameter Output voltage 1 Output voltage 2 Standby mode IC consumption current Operating time IC consumption current ENABLE high level voltage ENABLE low level voltage Efficiency Reference voltage FB pin bias current On resistance Soft start current Oscillation frequency Maximum on duty ratio Current limiting value Under voltage detection Under voltage detection hysteresis Thermal shutdown temperature Thermal shutdown temperature hysteresis *These are design guarantee values and no measurements are made. Symbol VOUT1 VOUT2 ICC1 ICC2 VENH VENL Effcy Vref Iref Ron ISS Fosc D max Icl Vl Vlh Ttsd Dtsd Design guarantee value* Design guarantee value* CBOOT=5V 3 145 85 4.1 3.3 0.15 3.7 0.185 180 20 4.2 0.25 IOUT=1A, VO=3.3V VIN=4.5V to 6V(±2%) 0.76 90 0.8 50 80 6.5 180 13 225 0.84 200 Conditions min FB2 pin selected Dependent on the external voltage divider ENABLE=0V ENABLE=3V 3 0.7 3.2 0.85 1 2 10 5 Ratings typ 3.3 max 3.4 V V µA mA V V % V nA mΩ µA kHz % A V V °C °C Unit No.A0663-2/7 LV5781 Package Dimensions unit : mm (typ) 3313 1.0 Pd max -- Ta Mounted on a specified board: 114.3mm×76.1mm×1.6mm, glass epoxy 14 8 Allowable power dissipation, Pd max - W 6.5 0.85 0.8 4.4 6.4 0.6 0.5 1 1.3 (2.35) 0.65 7 0.22 0.4 0.38 0.15 0.2 1.5max 0.1 (1.3) 0 -40 -20 0 20 40 60 80 100 Ambient temperature, Ta - °C 1.5 SANYO : HSSOP14(225mil) Block Diagram and Sample Application Circuits CBOOT VIN BOOT(SW+VIN) Pre-Drive FB_GND FB0 FB1 FB2 OERRAMP 6.5µA S/D OCP OSC 180kHz Error Amp PWM comparator SW VOUT SS 3.2V Enable Internal Reg ON OFF GND Vref 1.25V UVLO S/D TSD S/D No.A0663-3/7 LV5781 Pin Assignment and Sample Application Circuits G N D 1 FB_GND ON 2 ENABLE OFF 3 SS 4 FB1 5 VIN 6 SW 7 PGND G N D FB0 14 FB2 13 OERRAMP 12 CBOOT 11 VIN 10 SW 9 VIN 8 3.3V Sample Application Circuit 1 G N D 1 FB_GND ON 2 ENABLE OFF 3 SS 4 FB1 5 VIN 6 SW 7 PGND G N D FB0 14 FB2 13 OERRAMP 12 CBOOT 11 VIN 10 SW 9 VIN 8 VOUT Sample Application Circuit 2 *The capacitor between the FB0 and VOUT pins and capacitor between the OERRAMP pin and GND (the capacitors shown inside the broken lines in the diagram) are used for phase compensation. Their capacitance is intended to stop oscillation when oscillation is caused by the status of the output capacitor. As such, they can be left open under normal circumstances. No.A0663-4/7 LV5781 Pin Functions Pin No. 1 2 3 4 5, 8, 10 6, 9 7 11 12 13 14 Pin name FB_GND ENABLE SS FB1 VIN SW PGND CBOOT OERRAMP FB2 FB0 Description GND of output voltage setting pins FB0 and FB2. It is connected to GND for use when pin FB2 is used. Output ON/OFF with an active-high polarity. When set to L, the current consumption is reduced to 10µA or less. Soft start time constant setting. The charge current is set to approx. 6.5µA and when a capacitor of 0.1µF is connected between this pin and GND, the output rises in approx. 12ms. Test pin for verifying the internal reference voltage. It must be set to open for actual use. Power input. It is used with voltages ranging from 4.5V to 6V. Inductor drive output Power GND pin. This is the output GND. It is connected so that where at all possible, no impedance is shared with other GND pins (GND, FB_GND). For generating the gate voltage of the internal high-side n-channel MOS transistor. A capacitor with a capacitance of at least 0.1µF (max. 2.2µF) is connected between this pin and the SW pin for use. Transconductance-type Error_Amp output. An integration constant is provided between this pin and GND to implement phase compensation. Used to feed back the output voltage to this pin when the output voltage is to be set to 3.3V. In such a case, FB_GND is connected to GND. Refer to application circuit 1. When the output voltage is to be set to a desired value, connect resistors between FB0 and GND and between FB0 and VOUT to feed back the output voltage to this pin. In such a case, leave FB_GND and FB2 open. Refer to application circuit 2. Heat sink fin GND Analog GND (connected to GND). Input Equivalent Circuits Pin No. Pin Name GND 5, 8, 10 VIN Equivalent Circuit VIN GND 1 4 13 14 FB_GND FB1 FB2 FB0 VIN 116kΩ FB2 50kΩ FB1 118kΩ FB0 54.5kΩ FB_GND GND Continued on next page No.A0663-5/7 LV5781 Continued from preceding page Pin No. 2 Pin Name ENABLE Equivalent Circuit VIN 55kΩ ENABLE 100kΩ GND 3 SS VIN 6.5µA 300Ω FB0 300Ω 97kΩ Vref 100Ω SS GND 6, 9 7 11 SW PGND CBOOT CBOOT VIN SW PGND GND 12 OERRAMP VIN OERRAMP 1kΩ GND No.A0663-6/7 LV5781 SANYO Semiconductor Co.,Ltd. assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein. SANYO Semiconductor Co.,Ltd. strives to supply high-quality high-reliability products, however, any and all semiconductor products fail or malfunction with some probability. It is possible that these probabilistic failures or malfunction could give rise to accidents or events that could endanger human lives, trouble that could give rise to smoke or fire, or accidents that could cause damage to other property. When designing equipment, adopt safety measures so that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective circuits and error prevention circuits for safe design, redundant design, and structural design. In the event that any or all SANYO Semiconductor Co.,Ltd. products described or contained herein are controlled under any of applicable local export control laws and regulations, such products may require the export license from the authorities concerned in accordance with the above law. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any information storage or retrieval system, or otherwise, without the prior written consent of SANYO Semiconductor Co.,Ltd. Any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification" for the SANYO Semiconductor Co.,Ltd. product that you intend to use. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. Upon using the technical information or products described herein, neither warranty nor license shall be granted with regard to intellectual property rights or any other rights of SANYO Semiconductor Co.,Ltd. or any third party. SANYO Semiconductor Co.,Ltd. shall not be liable for any claim or suits with regard to a third party's intellctual property rights which has resulted from the use of the technical information and products mentioned above. This catalog provides information as January, 2007. Specifications and information herein are subject to change without notice. PS No.A0663-7/7