R7711A Primary Feedback CC/CV PWM Controller for Flyback Converters General Description Features Programmable Primary-Side CC/CV Regulation The R7711A is a current mode PWM controller which Low No Load Input Power (<30mW at 230V ) AC includes primary side voltage feedback technology. It Green Mode PWM Operation controls the output voltage and current accurately without Low Start-up Current (<10mA) shunt regulator and opto-coupler on secondary side to Triple Mode PWM Operation reduce the part count and save costs. Easy EMI Solution The R7711A is designed especially for low power Built-in Jittering Frequency applications, such as chargers for cell phones, PDAs, Built-in Soft Gate Driver and other mobile products. Complete protections are Programmable Cable Drop Compensation provided, such as output Under- Voltage Protection, output Adjustable Propagation Delay Compensation Over-Voltage Protection, VDD Over-Voltage Protection, VDD Over-Voltage Protection(VDDOVP) Over-Temperature Protection, and Secondary Rectifier Output Over-Voltage Protection(OVP) Short-circuit Protection. The ultra low start-up current and Output Under-Voltage Protection(UVP) operating current of the R7711A achieves low power Secondary Rectifier Short-Circuit Protection (SRSP) consumption in standby mode. The R7711A supports Internal Over-Temperature Protection(OTP) green-mode operation to meet CEC regulations and RoHS Compliant and Halogen Free Energy-Star requirements. Applications Switching AC/DC Adaptor and Battery Charger DVD Open Frame Power Supply STB Power Cell Phone Charger Networking Power Supply Simplified Application Circuit L V OUT AC Mains (90V to 265V) N DMAG VDD R7711A COMP GATE CS GND 2 Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. R7711A-03 November 2013 www.richtek.com 1R7711A Ordering Information Pin Configurations R7711A (TOP VIEW) Package Type CS COMP D MAG E : SOT-23-6 6 5 4 Lead Plating System G : Green (Halogen Free and Pb Free) 23 Note : GATE GND VDD Richtek products are : RoHS compliant and compatible with the current require- SOT-23-6 ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Marking Information FN= : Product Code FN=DNN DNN : Date Code Functional Pin Description Pin No. Pin Name Pin Function MOSFET Gate Driver Output. Connect this pin to the Gate of an external N-Channel 1 GATE power MOSFET. 2 GND Ground of the Controller. Power Supply Input. The controller will be enabled when V exceeds V and DD TH ON 3 VDD disabled when V decreases lower than V . DD TH OFF Demagnetization Pin. Input and Output Voltage Detection from Auxiliary Winding. The current (I ) flows into this pin to achieve cable drop compensation function. CABLE 4 DMAG This pin is also used to detect the signal of the rectified input voltage for propagation delay compensation and minimum on-time control. Feedback Compensation Pin. This pin is the output of the internal operational 5 COMP transconductance amplifier (OTA) to connect a proper RC network from this pin to GND for feedback loop compensation. Current Sensing Input. Connect this pin to a current sense resistor used to detect the 6 CS current of the primary-side winding. Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com R7711A-03 November 2013 2