RS2030G

Page No. : 1/7 RS2030X Lowest Cost Green-Power Off-Line PWM Controller Description The RS2030 is a high performance green-power offline power supply PWM controller. It features a scalable driver for driving external NPN (13003) or MOSFET transistors for line voltage switching. This proprietary architecture enables many advanced features to be integrated into a small package (TO-92), resulting in lowest total cost solution. The RS2030 automatically enters the CRM (Cycle Reset Mode) under light-load/zero-load conditions. Consuming only 0.15W in standby, the RS2030 features over-current, short circuits and under-voltage protection mechanisms. This can minimize standby power consumption and achieve green-power functions. With a very low start-up current, the RS2030 could use a large value start-up resistor Features Low Start-up Current 0.15W Standby Power Emitter Drive Allows Safe NPN Flyback Use Cycle-by-cycle current limiting Built-in Synchronized Slope Compensation Current Mode Operation Over-Current Protection (OCP) Short Circuits Protection (SCP) Under-voltage Protection with Auto-restart Proprietary Scalable Output Driver HBM ESD Voltage > 5000V 67kHz or 100kHz Fixed Switching Frequency Low EMI Technique Bullt-in high Voltage MOSFET (>30V) Selectable 400mA to800mA Current Limit Compatible with ACT30 & AP3700 Applications Battery Charger Adapter Standby Power Supplies Universal Off-Line Power Supplies Typical Application Circuit DS-RS2030X-EN-V1 Dec, 2007 www.Orister.com Page No. : 2/7 Pin Assignment & Description Pin 1 2 3 Name VDD GND SW Description Power Supply Pin. Connect to optocoupler's emitter. Internally limited to 5.6V max. Bypass to GND with a proper compensation network. Ground Output Pin. Connect to emitter of the high voltage NPN or MOSFET. RS2030X Part No. RS2030A RS2030B RS2030C RS2030D RS2030E RS2030F RS2030G RS2030H Freq. 67kHz 100kHz 67kHz 100kHz 67kHz 100kHz 67kHz 100kHz Peak Current 400mA 400mA 400mA 400mA 800mA 800mA 800mA 800mA Freq. Jitter Y Y N N Y Y N N Package TO-92 TO-92 TO-92 TO-92 TO-92 TO-92 TO-92 TO-92 Block Diagram DS-RS2030X-EN-V1 Dec, 2007 www.Orister.com Page No. : 3/7 Absolute Maximum Ratings PARAMETER VDD Pin Voltage VDD Current SW Pin Voltage SW Current Maximum Power Dissipation (TO-92) Operating Junction Temperature Storage Temperature Lead Temperature (Soldering, 10 sec) ESD Voltage (HBM) Value -0.3 ~ 6 20 -0.3~30 Internally limited 0.6 -40 ~+150 -55 ~+150 300 5500 Unit V mA V A W o C o C o C V Electrical Characteristics (Ta=27°C unless otherwise noted, VDD = 4.5V.) PARAMETER VDD Start Voltage SW Start Voltage VDD Under-voltage Threshold VDD Clamp Voltage Startup Supply Current VDD Supply Current Switching Frequency Maximum Duty Cycle Minimum Duty Cycle Effective Current Limit VDD to SW Current Coefficient VDD Dynamic Impedance SW Driver On-Resistance SW Rise Time SW Fall Time SW Switch Off Current SYMBOL VSTART VSWST VUV VVDD (Max) IDDST IDD fSW DMAX DMIN ILIM GGAIN RVDD RSW ISW=100mA 1nF load, 15Ω pull-up 1nF load, 15Ω pull-up Driver off RS2030A RS2030B VDD = 5.0V VDD = 5.0V VDD = VUV + 0.1V 380 760 62 90 62.7 Falling edge IVDD=10mA VDD = 4V before VUV TEST CONDITIONS Rising edge MIN 5.20 8.00 3.40 5.40 TYP 5.40 8.60 3.60 5.60 0.20 1.50 67 100 66.7 3.5 400 800 0.29 9 3.0 30 20 5 10 420 840 MAX 5.60 9.20 3.80 5.80 0.40 2.00 72 110 71.7 UNIT V V V V mA mA kHz % % mA A/V kΩ Ω ns ns uA DS-RS2030X-EN-V1 Dec, 2007 www.Orister.com Page No. : 4/7 OPERATION DESCRIPTION Current Model Compared to voltage model control, current model control has a current feedback loop. When the voltage of the sample resistor peak current of the primary winding reaches the internal setting value VTH, comparator reverse, register reset and power BJT or MOSFET cut-off. So that to detect and modulate the peak current cycle by cycle could control the output of the power supply. The current feedback has a good linear modulation rate and a fast input and output dynamic impact avoid the pole that the output filter inductance brings and the second class system descends to first class and so it widens the frequency range and optimizes overload protection and short circuit protection. Startup Current and Under Voltage Lockout The startup current of RS2030 is set to be very low (3uA) so that a large value startup resistor can therefore be used to minimize the power loss. For AC to DC adaptor with universal input range design, a 1.5 MΩ, 1/8 W startup resistor and a 10uF/25V VDD hold capacitor could be used. The turn-on and turn-off threshold of the RS2030 is designed to 5.4V/3.6V. During startup, the hold-up capacitor must be charge to 5.4V through the startup resistor. The hysteresis is implemented to prevent the shutdown from the voltage dip during startup. Green Power Operation The power dissipation of switching mode power supply is very important in zero load or light load condition. The major dissipation result from conduction loss、switching loss and consume of the control circuit. However, all of them related to the switching frequency. There are many difference topologies has been implemented in different chip. The basic operation theory of all these approaches intended to reduce the switching frequency under light-load or no-load condition. RS2030’s green power function adapts PWM、PFM and CRM combining modulation. The PWM frequency is 65kHz/100kHz in medium or heavy load operation. Through modifying the pulse width, RS2030 could control output voltage. To decrease the standby consumption of the power supply , Chip-Rail introduces the Cycle Reset Mode technology；If the feedback current were over 1.5mA, mode controller of RS2030 would reset internal register all the time and cut off the power BJT, while the output voltage is lower than the set value, it would set register, SW pin operating again. Although the frequency of the internal OSC is invariable, the register would reset some pulses so that the practical frequency is decreased at the SW pin. RS2030 Green-Power Function Internal Synchronized Slop Compensation Although there are more advantages of the current mode control than conventional voltage mode control, there are still several drawbacks of peak-sensing current-mode converter. Especially the open loop instability when it operates in higher than 50% of the duty-cycle. RS2030 is introduced an internal slope compensation adding voltage ramp to the current sense input voltage for PWM generation to solve this problem. It improves the close loop stability greatly at CCM, prevents the sub-harmonic oscillation and thus reduces the output ripple voltage. DS-RS2030X-EN-V1 Dec, 2007 www.Orister.com Page No. : 5/7 High/Low Voltage Power Compensation The current flowing by the power BJT has an extra value ΔI = VIN × TD due to the system delay TD that the current LP detected from the sense pin to power BJT cut off in the RS2030 (Among these, VIN is the primary winding voltage of the transformer and LP is the primary wind inductance, V IN ranges from 85VAC to 264VAC.) To guarantee the output power is a constant for universal input AC voltage, there is a dynamic peak limit circuit to compensate the system delay TD that the system delay brings on. Soft Start The VDD pin of the RS2030 is the power supply voltage pin and the feedback pin, so the duty cycle will be increase with VDD voltage decreasing. The soft start performance have been implemented by increasing the duty cycle in starting. Leading-edge Blanking (LEB) Each time the power BJT is switched on, a turn-on spike will inevitably occur at the sense pin, which would disturb the internal signal from the sampling of the RSENSE. There is a 250n sec leading edge blanking time built in to avoid the effect of the turn-on spike and the power BJT cannot be switched off during this time. So that the conventional external RC filtering on sense input is no longer required. Short Circuit Protection (SCP) When the output circuit is shorted, the restart time of the RS2030 and the input power will be increased with input voltage increasing, then the power NPN BJT will be hot and destroyed. So the Chip-Rail secondary delay circuit has been introduced for decrease the restart time. TO-92 Dimension α2 DIM A B C D E F G H I α1 α2 α3 Min. 4.33 4.33 12.70 0.36 3.36 0.36 Max. 4.83 4.83 0.56 *1.27 3.76 0.56 *2.54 *1.27 *5° *2° *2° A B 1 2 3 α3 C D H I E 3-Lead TO-92 Plastic Package Package Code: A G *: Typical, Unit: mm α1 F DS-RS2030X-EN-V1 Dec, 2007 www.Orister.com Page No. : 6/7 Soldering Methods for Orister’s Products 1. Storage environment: Temperature=10oC~35oC Humidity=65%±15% 2. Reflow soldering of surface-mount devices Figure 1: Temperature profile tP TP Ramp-up TL Tsmax Temperature tL Critical Zone TL to TP Tsmin tS Preheat Ramp-down 25 t 25oC to Peak Time Profile Feature Average ramp-up rate (TL to TP) Preheat - Temperature Min (Tsmin) - Temperature Max (Tsmax) - Time (min to max) (ts) Tsmax to TL - Ramp-up Rate Time maintained above: - Temperature (TL) - Time (tL) Peak Temperature (TP) Time within 5oC of actual Peak Temperature (tP) Ramp-down Rate Time 25oC to Peak Temperature 3. Flow (wave) soldering (solder dipping) Products Pb devices. Pb-Free devices. Sn-Pb Eutectic Assembly