�8�7INTRODUCTION:
�8�7 The CE8425 devices provide a power supply solution for products powered by either a one-cell Li-Ion or Li-polymer, or a two to three-cell alkaline, NiCd or NiMH battery. The converter generates a stable output voltage that is either adjusted by an external resistor pider or fixed internally on the chip. It provides high efficient power conversion and is capable of delivering output currents up to 1.5A at 5V at a supply voltage down to 2V. The implemented boost converter is based on a fixed switching frequency (500kHz typical), current-mode controller using a synchronous rectifier to obtain maximum efficiency. Boost switch and rectifier switch are connected internally to provide the lowest leakage inductance and best EMI behavior possible. The current-mode control scheme provides fast transient response and good output voltage accuracy. At light load, the converter will automatically enter into Pulse Frequency Modulation (PFM) operation to reduce the dominant switching losses. During PFM operation, the IC consumes very low quiescent current and maintains high efficiency over a wide load current range. The converter can be disabled to minimize battery drain. During shutdown, the load is completely disconnected from the battery. A low-EMI mode is implemented to reduce ringing and, in effect, lower radiated electromagnetic energy when the converter enters the discontinuous conduction mode The device allows use of small inductors and output capacitors for USB devices.
FEATURES:
�8�5 97% Efficiency at VOUT=5V from 3.3V Input
�8�5 Device Quiescent Current: 37μA (Typ)
�8�5 Guaranteed 2.5A Output Current at VOUT=5V from 3.3V Input
�8�5 500kHz PWM Switching Frequency
�8�5 Synchronous and Embedded Power
MOSFETs, No Schottky Diode Required
�8�5 Low RDS(ON) (main switch/synchronous switch) at 5.0V output: 20/40mohm
�8�5 Input Voltage Range: 1.8V to 5.25V
�8�5 Fixed and Adjustable Output Voltage Options
from 2.5V to 5.5V
�8�5 5A Peak Switch Current Limit
�8�5 Input Under Voltage Lockout
�8�5 Load Disconnect During Shutdown
�8�5 Output Over Voltage Protection
�8�5 Low Battery Comparator
�8�5 Internal Soft-Start to Limit Inrush Current
�8�5 Pulse Frequency Modulation Operation for Improved Efficiency at Low Output Power
�8�5 Low EMI-Converter
(Integrated Anti-ringing Switch)
�8�5 Current Mode Operation with Internal
Compensation for Excellent Line and Load Transient Response
�8�5 Logic Controlled Shutdown(<1μA)
�8�5 Over-Temperature Protection
�8�5 Available in 2.1mm x 2.1mm QFN10 Package
�8�5 Lead Free and Green Devices Available
(RoHS Compliant)
�8�7APPLICATIONS：
�8�5 All Single Cell Li or Dual Cell Battery Operated Products as Tablet PC, Smartbook and Other Portable Equipment
�8�5 USB Hosts Without Native 5V Supplies
�8�5 USB Charging Port (5V)
�8�5 DC/DC Micro Modules
�8�5 Portable Audio Players
�8�5 Power Bank
5A, 500KHz Synchronous Boost Converter with Output Disconnect
替代SY7065,性价比高.2.5A移动电源同步整流方案最佳升压IC
公司名称： 深圳市新泰陞科技有限公司
姓名： 陈俐玲
电话： 86655148
传真：0755-83286065
QQ : 485406174
手机： 13480315997
地址：深圳市南山区深南大道与前海路交汇处海岸卡夫诺东座2314
