SG5841/J FEATURES APPLICATIONS DESCRIPTION TYPICAL APPLICATION. Product Specification. Highly-Integrated Green-Mode PWM Controller

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1 FEATURES Green-mode PWM Controller Low Start-Up Current (4uA) Low Operating Current (4mA) Programmable PWM frequency with Hopping Peak-current-mode Control Cycle-by-Cycle Current Limiting Synchronized Slope Compensation Leading-Edge Blanking Constant Output Power Limit Totem Pole Output with Soft Driving VDD Over Voltage Clamping Programmable Over Temperature Protection (OTP) Internal Open-loop Protection V DD Under-voltage Lockout (UVLO) GATE Output Maximum Voltage Clamp (8V) APPLICATIONS General-purpose switch-mode power supplies and flyback power converters, including: Power Adapters Open-Frame SMPS DESCRIPTION The highly integrated series of PWM controllers provides several features to enhance the performance of flyback converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency at light-load conditions. This green-mode function enables the power supply to easily meet international power conservation requirements. To further reduce power consumption, is manufactured by using the BiCMOS process. This allows the lowest start-up current around 4uA, and the operating current is only 4mA. As a result, large start-up resistance can be used. s built-in synchronized slope compensation achieves stable peak-current-mode control. The proprietary internal saw-tooth power-limiter ensures constant output power limit over a wide AC input voltages, from 90VAC to 64VAC. provides many protection functions. In addition to cycle-by-cycle current limiting, the internal open-loop protection circuit ensures safety should an open-loop or output-short-circuit failure occurs. PWM output is disabled till V DD drops below the UVLO lower limit. Then, the controller starts up again. For OTP, an external NTC thermistor can be applied for over-temperature protection. is available in an 8-pin DIP or SOP package. TYPICAL APPLICATION System General Corp

2 MARKING DIAGRAMS PIN CONFIGURATION SG584HTP XXXXXXXXYWWV H: J = with Frequency Hopping Null = without Frequency Hopping T: D = DIP, S = SOP P: Z = Lead Free Null=regular package XXXXXXXX: Wafer Lot Y: Year; WW: Week V: Assembly Location GND FB VIN RI GATE VDD SENSE RT ORDERING INFORMATION Part Number Frequency Hopping Package SG584JSZ Yes 8-Pin SOP (Lead Free) SG584JDZ Yes 8-Pin DIP (Lead Free) SG584SZ No 8-Pin SOP (Lead Free) SG584DZ No 8-Pin DIP (Lead Free) PIN DESCRIPTIONS Pin No. Symbol Function Description GND Ground Ground. FB Feedback 3 VIN Start-Up Input 4 RI 5 RT Reference Setting Temperature Detection 6 SENSE Current Sense The signal from the external compensation circuit is fed into this pin. The PWM duty cycle is determined in response to the signal from this pin and the current-sense signal from Pin 6. If FB voltage exceeds a threshold, the internal protection circuit will disable PWM output after a predetermined delay time. For start-up, this pin is pulled high to the rectified line input via a resistor. Since the start-up current requirement of the is very small, a large start-up resistance can be used to minimize power loss. A resistor connected from the RI pin to GND pin will provide the with a constant current source. This determines the center PWM frequency. Increasing the resistance will reduce PWM frequency. Using a 6KΩ resistor RI results in a 65KHz center PWM frequency. For over-temperature protection. An external NTC thermistor is connected from this pin to GND pin. The impedance of the NTC will decrease at high temperatures. Once the voltage of the RT pin drops below a fixed limit, PWM output will be disabled. Current sense. The sensed voltage is used for peak-current-mode control and cycle-by-cycle current limiting. 7 VDD Power Supply Power Supply. If VDD exceeds a threshold, the internal protection circuit will disable PWM output. 8 GATE Driver Output The totem-pole output driver for the power MOSFET. It is internally clamped below 8V System General Corp

3 BLOCK DIAGRAM 584J only System General Corp

4 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit V VDD Supply Voltage 30 V V VIN Input Terminal 30 V V FB Input Voltage to FB Pin -0.3 to 7 V V SENSE Input Voltage to SENSE Pin -0.3 to 7 V V RT Input Voltage to RT Pin -0.3 to 7 V V RI Input Voltage to RI Pin -0.3 to 7 V P D Power Dissipation (T A < 50 C ) RΘ j-a RΘ j-c Thermal Resistance (Junction-Air) Thermal Resistance (Junction-Case) DIP 800 SOP 400 DIP 8.5 SOP 4 DIP 59.7 SOP 80.8 T J Operating Junction Temperature -40 to +5 C T STG Storage Temperature Range -55 to +50 C T L Lead Temperature (Wave soldering or IR, 0 seconds) 60 C V ESD,HBM ESD Capability, HBM Model 3.0 KV V ESD,MM ESD Capability, Machine Model 50 V * All voltage values, except differential voltages, are given with respect to GND pin. * Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. mw C/W C/W RECOMMENDED OPERATING CONDITIONS Symbol Parameter Value Unit T A Operating Ambient Temperature -0 to +85 C * For proper operation ELECTRICAL CHARACTERISTICS (VDD = 5V, T A = 5 C, unless noted) VDD Section Symbol Parameter Test Condition Min. Typ. Max. Unit V DD-OP Continuously Operating Voltage 4.7 V V DD-ON Start Threshold Voltage V V DD-OFF Minimum Operating Voltage 9 0 V I DD-ST Start-up Current V DD =V DD-ON 0.6V 4 30 ua I DD-OP Operating Supply Current V DD =5V, RI=6KΩ, GATE=OPEN 4 5 ma V DD-CLAMP V DD Over-voltage-clamping level 8 9 V t D-VDDCLAMP V DD Over-voltage-clamping Debounce Time RI=6KΩ us RI Section Symbol Parameter Test Condition Min. Typ. Max. Unit RI NOR RI Operating Range KΩ RI MAX Max. RI value for Protection 30 KΩ RI MIN Min. RI value for Protection 0 KΩ System General Corp

5 Oscillator Section Symbol Parameter Test Condition Min. Typ. Max. Unit F OSC Normal PWM Frequency Center Frequency RI=6KΩ Hopping Range RI=6KΩ (584J only) ±3.7 ±4. ±4.7 t HOP Hopping Period RI=6KΩ (584J only) ms F OSC-G Green-mode Frequency RI=6KΩ 8 5 KHz F DV Frequency Variation Versus V DD Deviation V DD =.5V to 4.7V 5 % F DT Frequency Variation Versus Temp. Deviation T A =-0 to 85 C 5 % KHz Feedback Input Section Symbol Parameter Test Condition Min. Typ. Max. Unit A V FB Input to Current Comparator Attenuation /3.75 /3. /.75 V/V Z FB Input Impedance 4 7 KΩ V FB-OPEN FB Output High Voltage FB pin open 5 6 V V FB-OLP FB Open-loop Trigger Level V t D-OLP The delay time of FB pin Open Loop Protection RI=6KΩ ms V FB-N Green-mode Entry FB Voltage RI=6KΩ.9..3 V V FB-G Green-mode Ending FB Voltage RI=6KΩ V FB-N -0.5 V Current-Sense Section Symbol Parameter Test Condition Min. Typ. Max. Unit Z SENSE Input Impedance KΩ V STHFL Current Limit Flatten Threshold Voltage V V STHVA Current Limit Valley Threshold Voltage V STHFL V STHVA 0. V t PD Propagation Delay to GATE Output RI=6KΩ ns t LEB Leading Edge Blanking Time RI=6KΩ ns System General Corp

6 GATE Section Symbol Parameter Test Condition Min. Typ. Max. Unit DCY MAX Maximum Duty Cycle % V GATE-L Output Voltage Low V DD =5V, I O =50mA.5 V V GATE-H Output Voltage High V DD =.5V, I O =50mA 7.5 V tr Rising Time V DD =5V, C L =nf ns tf Falling Time V DD =5V, C L =nf ns I O Peak Output Current V DD =5V, GATE=6V 30 ma V GATE-CLAMP Gate Output Clamping Voltage V DD =4.7V 8 9 V RT Section Symbol Parameter Test Condition Min. Typ. Max. Unit I RT Output Current of RT pin RI=6KΩ ua V RTTH V RT-RLS Trigger Voltage for Over-temperature Protection OTP Release Voltage V V RTTH t D-OTP Over-temperature Debounce. RI=6KΩ us V System General Corp

7 TYPICAL CHARACTERISTIC Start-up Current (IDD-ST) vs Temperature Operating Supply Current (IDD-OP) vs Temperature IDD-ST (ua) 8 4 IDD-OP (ma) Operation Current (IDD-OP) vs VDD Voltage 7.0 Start Threshold Voltage (VDD-ON) vs Temperature IDD-OP (ma) GATE = 000pF GATE = OPEN V DD-ON (V) VDD Voltage (V) V DD-OFF (V) Min. Operating Voltage (VDD-OFF) vs Temperature Fosc (Khz) PWM Frequency (Fosc) vs Temperature System General Corp

8 70 Max. Duty Cycle (DCYMAX.) vs Temperature Trigger Voltage for Over-temperature Protection (VRTTH) vs Temperature DCY MAX. (%) V (RTTH) (V) Output Current of RT pin (IRT) vs Temperature IRT (ua) System General Corp

9 OPERATION DESCRIPTION Start-up current Typical start-up current is only 4uA so that a high resistance, and low-wattage, start-up resistor can be used to minimize power loss. For an AC/DC adapter with universal input range, a.5 MΩ, 0.5W, start-up resistor and a 0uF/5V VDD hold-up capacitor are enough for this application. Operating current Operating current is around 4mA. The low operating current enables a better efficiency and reduces the requirement of V DD hold-up capacitance. Green Mode Operation The proprietary green-mode function provides off-time modulation to continuously decrease the PWM frequency under light-load conditions. To avoid acoustic-noise problem, the minimum PWM frequency set above khz. This green-mode function dramatically reduces power consumption under light-load and zero-load conditions. Power supplies using a controller can easily meet even the most restrictive international regulations regarding standby power consumption. Oscillator Operation A resistor connected from the RI pin to GND pin generates a constant current source for the controller. This current is used to determine the center PWM frequency. Increasing the resistance will reduce PWM frequency. Using a 6KΩ resistor RI results in a corresponding 65KHz PWM frequency. The relationship between RI and the switching frequency is: 690 f PWM = (KHz) () R I (KΩ) The range of the PWM oscillation frequency is designed as 47KHz ~ 09KHz. SG584J also integrates frequency hopping function internally. The frequency variation ranges from around 6KHz to 68KHz for a center frequency 65KHz. The frequency hopping function helps reduce EMI emission of a power supply with minimum line filters. Current sensing and PWM current limiting Peak-current-mode control is utilized in to regulate output voltage and provide pulse-by-pulse current limiting. The switch current is detected by a sense resistor into the SENSE pin. The PWM duty cycle is determined by this current sense signal and V FB, the feedback voltage. When the voltage on SENSE pin reaches around V COMP = (V FB.0)/3., a switch cycle will be terminated immediately. V COMP is internally clamped to a variable voltage around 0.85V for output power limit. Leading Edge Blanking Each time the power MOSFET is switched on, a turn-on spike will inevitably occur at the sense-resistor. To avoid premature termination of the switching pulse, a leading-edge blanking time is built in. During this blanking period, the current-limit comparator is disabled, and it cannot switch off the gate drive. Under-voltage lockout (UVLO) The turn-on and turn-off threshold of are fixed internally at 6V/0V. During start-up, the hold-up capacitor must be charged to 6V through the start-up resistor so that IC will be enabled. The hold-up capacitor will continue to supply V DD before the energy can be delivered from auxiliary winding of the main transformer. V DD must not drop below 0V during this start-up process. This UVLO hysteresis window insures that hold-up capacitor is adequate to supply V DD during start-up. Gate Output / Soft Driving The BiCMOS output stage is a fast totem pole gate driver. Cross conduction has been avoided to minimize heat dissipation, increases efficiency and enhances reliability. The output driver is clamped by an internal 8V Zener diode in order to protect power MOSFET transistors against undesirable gate over voltage. A soft driving waveform is implemented to minimize EMI. Built-in Slope Compensation The sensed voltage across the current-sense resistor is used for peak-current-mode control and pulse-by-pulse current limiting. Built-in slope compensation will improve stability or prevent sub-harmonic oscillation. inserts a synchronized positive-going ramp at every switching cycle. System General Corp

10 Constant Output Power Limit When the SENSE voltage, across the sense resistor Rs, reaches the threshold voltage, around 0.85V, the output GATE drive will be turned off after a small delay t PD. This delay will introduce an additional current proportional to t PD * V IN / L P. Since the delay is nearly constant regardless of the input voltage V IN. Higher input voltage will result in a larger additional current and hence the output power limit is also higher than that under low input line voltage. To compensate this variation for wide AC input range, a saw-tooth power-limiter (saw limiter) is designed to solve the unequal power-limit problem. The saw limiter is designed as a positive ramp signal (Vlimit ramp) and is fed to the inverting input of the OCP comparator. This results in a lower current limit at high-line inputs than at low-line inputs. VDD Over-voltage Clamping VDD over-voltage Clamping has been built in to prevent damage due to abnormal conditions. Once the VDD voltage is over than the VDD over voltage clamping voltage (V DD-CLAMP ), and lasts for t D-VDDCLAMP, the PWM pulses will be disable until the VDD voltage drops below the VDD over voltage clamping voltage. When VDD goes below the turn-off threshold (e.g., 0V) the controller will be totally shut down. VDD will be charged up to the turn-on threshold voltage of 6V through the start-up resistor until PWM output is restarted. This protection feature will continue to be activated as long as the over-loading condition persists. This will prevent the power supply from overheating due to over loading conditions. Noise immunity Noise on the current sense or control signal may cause significant pulse width jitter, particularly in the continuous-conduction mode. Slope compensation helps alleviate this problem. Good placement and layout practices should be followed. Avoiding long PCB traces and component leads, locating compensation and filter components near to the, and increasing the power MOS gate resistance will always help. Thermal Protection An NTC thermistor R NTC in series with a resistor Ra can be connected from pin RT to ground. A constant current I RT is output from pin RT. The voltage on RT pin can be expressed as V RT = I RT (R NTC + Ra), in which I RT = x (.3V / R I ). At high ambient temperature, R NTC will be smaller such that V RT will decrease. When V RT is less than 0.6V, the PWM will be completely turned off. Limited Power Control The FB voltage will increase every time the output of the power supply is shorted or over-loaded. If the FB voltage remains higher than a built-in threshold for longer than t D-OLP, PWM output will then be turned off. As PWM output is turned off, the supply voltage VDD will also begin decreasing. t D - OLP (ms) =.5 RI(K Ω ) () System General Corp

11 REFERENCE CIRCUIT Circuit CN 3 F VZ TR L 3 4 C R R L 3 4 C C5 4 BD 3 C4 + R5 C3 R7 D R3 D4 T 3 C6 Q R4 C7 + L3 +C8 D3 R6 Vo+ D 3 4 R9 U GND GATE FB VDD VIN SENSE RI RT R0 C R6 Q 3 C9 + R8 R R THER 4 U C R3 3 C0 U3 A K R R5 R4 VO+ BOM Reference Component Reference Component BD BD 4A/600V Q MOS 7A/600V C XC 0.68uF/300V R,R R Mohm /4W C XC 0.uF/300V R3 R 00Kohm /W C3 CC 0.0uF/500V R4 R 47ohm /4W C4 EC 0u/400V R5,R7 R 750Kohm /4W C5 YC p/50v R6 R Kohm /8W C6 CC 000pF/00V R8 R 0.3ohm W C7 EC 000uF/5V R9 R 33Kohm /8W C8 EC 470uF/5V R0 R 4.7Kohm /8W % C9 EC 0uF/50V R R 470ohm /8W C0 CC pf/50v R R 0 ohm /8W C CC 470pF/50V R3 R 4.7Kohm /8W C CC 0pF/50V(Option) R4 R 54Kohm /8W D LED R5 R 39Kohm /8W D Diode BYV95C R6 R 00ohm /8W D3 TVS P6KE6A THER Thermistor TTC04 D4 Diode FR03 T Transformer (600uH-PQ60) F FUSE 4A/50V U IC L Choke (900uH) U IC PC87 L Choke (0mH) U3 IC TL43 L3 Inductor (uh) VZ VZ 9G Q Diode 0A/00V System General Corp

12 PACKAGE INFORMATION 8PINS-DIP (D) D 8 5 Θ E E eb 4 A A A L b b e Dimensions Symbol Millimeters Inches Min. Typ. Max. Min. Typ. Max. A A A b b D E E e L eb θ System General Corp

13 8PINS-SOP(S) 8 5 C E H F 4 b e D A A Θ L Dimensions Symbol Millimeter Inch Min. Typ. Max. Min. Typ. Max. A A b c D E e F 0.38X X45 H L θ System General Corp

14 DISCLAIMERS LIFE SUPPORT System General s products are not designed to be used as components in devices intended to support or sustain human life. Use of System General s products in components intended for surgical implant into the body, or other applications in which failure of System General s products could create a situation where personal death or injury may occur, is not authorized without the express written approval of System General s Chief Executive Officer. System General will not be held liable for any damages or claims resulting from the use of its products in medical applications. MILITARY System General's products are not designed for use in military applications. Use of System General s products in military applications is not authorized without the express written approval of System General s Chief Executive Officer. System General will not be held liable for any damages or claims resulting from the use of its products in military applications. RIGHT TO MAKE CHANGES System General reserves the right to change this document and/or this product without notice. Customers are advised to consult their System General sales representative before ordering. System General Corp