OB2571TCPA

OB2571x High Performance QR mode Primary-Side Power Switch GENERAL DESCRIPTION FEATURES  Primary-side sensing and regulation operates in QR mode without TL431 and opto-coupler  High precision constant voltage and current regulation at universal AC input  Programmable CV and CC regulation  Integrated power MOSFET  Good dynamic response  Programmable Brownout Protection and Line OVP Protection(For 2571Lx only)  Built-in line compensation for tight CC regulation  Built-in fixed cable compensation  Built-in primary winding inductance compensation  Built-in control loop compensation  Built-in leading edge blanking (LEB)  Ultra low start-up current and low operating current  Comprehensive protection coverage with auto-recovery  VDD over voltage protection (VDD OVP)  VDD under voltage lockout with hysteresis (UVLO)  Cycle-by-cycle current limiting  Feedback open loop protection (OLP)  Output short circuit protection (SCP) OB2571x is an excellent primary side regulation controller with CC/CV operation for medium level power AC/DC charger and adapter applications. The device integrates an internal power MOSFET and operates in QR mode to provide high efficiency along with several functions of built-in protections. It removes the need for secondary feedback circuitry to lower the total bill of material cost. Proprietary Constant Voltage (CV) and Constant Current (CC) control is integrated as shown in the figure below. In CV control, the controller changes the mode of operation according to load condition. At full loading, the controller operates in quasi-resonant (QR) mode in the universal line voltage. The primary side regulation power supplies up to high power without the efficiency limitation of DCM or audible noise. In CC control, OB2571x samples the Vcs peak current and the demagnetization pulse to regulation the output current. The current and output power setting can be adjusted externally by the sense resistor Rs at CS pin. OB2571x offers comprehensive protection coverage with auto-recovery feature including Cycle-by-Cycle current limiting, VDD OVP, OLP, SCP, OTP etc. OB2571x consumes less than 75mW input power at no- load condition with high line voltage. OB2571x is offered in SOP8 package. APPLICATIONS Medium level Power AC/DC offline SMPS for  Cell phone charger  Tablet PC  AC/DC adapter  Set-top box power supplies Figure.1. Typical CC/CV Curve TYPICAL APPLICATION ©On-Bright Electronics Confidential -1- Datasheet OB_DOC_DS_2571xA0 OB2571x High Performance QR mode Primary-Side Power Switch GENERAL INFORMATION Pin Configuration The pin map is shown as below for SOP8. 1 8 DRAIN 2 7 DRAIN GND 3 6 DRAIN CS 4 5 DRAIN VDD FB Absolute Maximum Ratings Parameter VDD Voltage FB Input Voltage Drain Voltage (off state) CS Input Voltage Min/Max Operating Junction Temperature TJ Operating Ambient Temperature TA Min/Max Storage Temperature Tstg Lead Temperature (Soldering, 10secs) Ordering Information Part Number Description OB2571TCP SOP8, Halogen-free in Tube OB2571TCPA SOP8, Halogen-free in T&R OB2571ATCP-H SOP8, Halogen-free in Tube OB2571ATCPA-H SOP8, Halogen-free in T&R OB2571LTCP-H SOP8, Halogen-free in Tube OB2571LTCPA-H SOP8, Halogen-free in T&R OB2571ALTCP SOP8, Halogen-free in Tube OB2571ALTCPA SOP8, Halogen-free in T&R Value -0.3 to 30V -0.3 to 7V -0.3 to Bvdss -0.3 to 7V -40 to 150 ℃ -20 to 85 ℃ -55 to 150 ℃ 260 ℃ Note: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute maximum-rated conditions for extended periods may affect device reliability. Recommended Operating Condition Symbol Parameter Range VDD VDD Supply Voltage 9 to 25V Package Dissipation Rating Package RθJA (℃/W) SOP8 85 OB2571x High Performance QR mode Primary-Side Power Switch X X Package - X Package Green P:Halogen-free C:SOP8 ©On-Bright Electronics X Confidential -2- Packing BVdss Blank:Tube H:650V A: Tape/Reel Datasheet OB_DOC_DS_2571xA0 OB2571x High Performance QR mode Primary-Side Power Switch Marking Information YWWZZZ OB2571TCP A S Y:Year Code WW:Week Code(01-52) ZZZ:Lot Code C:SOP8 Package P:Halogen-free Package A:Character Code S:Internal Code(Optional) YWWZZZ OB2571TCP AL S Y:Year Code WW:Week Code(01-52) ZZZ:Lot Code C:SOP8 Package P:Halogen-free Package AL:Character Code S:Internal Code(Optional) TERMINAL ASSIGNMENTS Pin Num Pin Name I/O 1 VDD P Power Supply 2 FB I The voltage feedback from auxiliary winding. Connected to resistor divider from auxiliary winding reflecting output voltage. 3 GND P Ground 4 CS I Current sense input. Connect a sense resistor from this pin to ground. 5,6,7,8 DRAIN O Internal MOSFET DRAIN output ©On-Bright Electronics Description Confidential -3- Datasheet OB_DOC_DS_2571xA0