Critical Conduction Mode PFC Control IC SSC2016S Data Sheet Description Package SSC2016S is a Critical Conduction Mode (CRM) control IC for power factor correction (PFC). Since no input voltage sensing is required, the IC allows the realization of low standby power and the low number of external components. The product achieves high cost-performance and high efficiency PFC converter system. SOIC8 FB 1 8 VCC CT 2 7 OUT COMP 3 6 GND CS 4 5 ZCD Not to Scale Features ● Low Standby Power (No input voltage sensing required) ● Maximum Switching Frequency Limitation Function ● Minimum On-time Limitation Function ● Restart Function ● Protection Functions − Overcurrent Protection 1 (OCP1): Pulse-by-pulse − Overcurrent Protection 2 (OCP2): Latched shutdown − Overvoltage Protection (OVP): Auto-restart − FB Pin Undervoltage Protection (FB_UVP): Auto-restart − Thermal Shutdown Protection with hysteresis (TSD): Auto-restart Typical Application DBYP BR1 Electrical Characteristics ● VCC pin absolute maximum ratings, VCC = 28 V ● OUT pin source current, IOUT(SRC) = −500 mA ● OUT pin sink current, IOUT(SNK) = 1000 mA Application PFC circuit up to 200 W of output power such as: ● AC/DC Power Supply ● Digital appliances (large size LCD television and so forth). ● OA equipment (Computer, Server, Monitor, and so forth). ● Communication facilities ● Other Switching Mode Power Supply, SMPS DFW P VAC D1 T1 VOUT R2 Q1 D R3 C1 R4 C2 RVS1 R1 RCS LINE GND R5 U1 C5 ZCD 5 6 C7 External power supply 7 8 NC C6 CS GND COMP OUT CT VCC FB SSC2016S 4 RS CS 3 CP 2 C4 1 C3 RVS2 TC_SSC2016S_1_R2 SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 1 SSC2016S CONTENTS Description ------------------------------------------------------------------------------------------------------ 1 CONTENTS ---------------------------------------------------------------------------------------------------- 2 1. Absolute Maximum Ratings ----------------------------------------------------------------------------- 3 2. Electrical Characteristics -------------------------------------------------------------------------------- 4 3. Block Diagram --------------------------------------------------------------------------------------------- 6 4. Pin Configuration Definitions --------------------------------------------------------------------------- 6 5. Typical Application --------------------------------------------------------------------------------------- 7 6. External Dimensions -------------------------------------------------------------------------------------- 8 7. Marking Diagram ----------------------------------------------------------------------------------------- 8 8. Operational Description --------------------------------------------------------------------------------- 9 8.1 Critical Conduction Mode: CRM ---------------------------------------------------------------- 9 8.2 Startup Operation --------------------------------------------------------------------------------- 10 8.2.1 To Use an External Power Supply ------------------------------------------------------- 10 8.2.2 To Use an Auxiliary Winding ------------------------------------------------------------- 10 8.3 Restart Circuit ------------------------------------------------------------------------------------- 11 8.4 Maximum On-time Setting ---------------------------------------------------------------------- 11 8.5 Zero Current Detection and Bottom-on Timing Setting ----------------------------------- 11 8.6 Maximum Switching Frequency Limitation Function ------------------------------------- 12 8.7 Overcurrent Protection (OCP) ----------------------------------------------------------------- 12 8.8 Overvoltage Protection (OVP) ------------------------------------------------------------------ 13 8.9 FB Pin Under Voltage Protection (FB_UVP) ------------------------------------------------ 13 8.10 Thermal Shutdown (TSD) ----------------------------------------------------------------------- 13 9. Design Notes ---------------------------------------------------------------------------------------------- 13 9.1 Inductor Design ------------------------------------------------------------------------------------ 13 9.1.1 Boost winding, P ----------------------------------------------------------------------------- 14 9.1.2 Auxiliary Winding, D ----------------------------------------------------------------------- 14 9.2 External Components ---------------------------------------------------------------------------- 16 9.2.1 FB Pin Peripheral Circuit (Output VoltageDetection) ------------------------------- 16 9.2.2 COMP Pin Peripheral Circuit, RS, CS and CP ----------------------------------------- 16 9.2.3 CT Pin Peripheral Circuit, C4 ------------------------------------------------------------ 16 9.2.4 CS Pin Peripheral Circuit, RCS, R5 and C5 -------------------------------------------- 16 9.2.5 ZCD Pin Peripheral Circuit, R1 and C6 ------------------------------------------------ 17 9.2.6 OUT Pin Peripheral Circuit (Gate Drive Circuit) ------------------------------------ 17 9.2.7 VCC Pin Peripheral Circuit --------------------------------------------------------------- 17 9.2.8 Power MOSFET, Q1 ------------------------------------------------------------------------ 18 9.2.9 Boost Diode, DFW ---------------------------------------------------------------------------- 18 9.2.10 Bypass Diode, DBYP -------------------------------------------------------------------------- 18 9.2.11 Output Capacitor, C2 ---------------------------------------------------------------------- 19 9.3 PCB Trace Layout and Component Placement --------------------------------------------- 19 10. Reference Design of Power Supply ------------------------------------------------------------------ 21 OPERATING PRECAUTIONS -------------------------------------------------------------------------- 23 IMPORTANT NOTES ------------------------------------------------------------------------------------- 24 SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 2 SSC2016S 1. Absolute Maximum Ratings ● The polarity value for current specifies a sink as “+”, and a source as “−”, referencing the IC. ● Unless specifically noted TA = 25 °C Parameter Symbol Conditions Pins Rating Unit FB Pin Voltage VFB 1–6 − 0.3 to 5 V CT Pin Voltage VCT 2–6 − 0.3 to 5 V COMP Pin Voltage VCOMP 3–6 − 0.3 to 5 V COMP Pin Current ICOMP 3–6 − 100 to 100 µA VCS(DC) 4–6 − 0.3 to 5 V 4–6 − 2 to 5 V CS Pin Voltage (DC) CS Pin Voltage (Pulse) VCS(PULSE) Pulse with =1µs ZCD Pin Voltage VZCD 5–6 − 10 to 10 V ZCD Pin Current IZCD 5–6 − 10 to 10 mA OUT Pin Voltage VOUT 7–6 − 0.3 to VCC + 0.3 V OUT Pin Source Current IOUT(SRC) 7–6 − 500 mA OUT Pin Sink Current IOUT(SNK) 7–6 1000 mA VCC Pin Voltage VCC 8–6 28 V Allowable Power Dissipation PD − 0.5 W Operating Ambient Temperature TOP − −40 to 110 °C Storage Temperature Tstg − −40 to 150 °C Junction Temperature Tj − 150 °C SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 Note 3 SSC2016S 2. Electrical Characteristics ● The polarity value for current specifies a sink as “+”, and a source as “−”, referencing the IC. ● Unless specifically noted, TA = 25 °C, VCC = 14 V Parameter Symbol Conditions Pins Min. Typ. Max. Unit Power Supply Operation Operation Start Voltage VCC(ON) 8–6 7.5 8.5 9.5 V Operation Stop Voltage VCC(OFF) 8–6 6.5 7.5 8.5 V Operation Voltage Hysteresis VCC(HYS) 8–6 0.5 1.0 1.5 V Circuit Current in Operation ICC(ON) 8–6 1.2 2.1 3.2 mA Circuit Current in Non-Operation ICC(OFF) 8–6 – 50 100 µA 1–6 0.2 0.7 1.4 µA 1–6 2.475 2.500 2.525 V 1–6 − 8.0 1.0 12.0 mV VCC = 7 V Frequency Control FB Pin Sink Current IFB Feedback Voltage Reference VREF VREF Line Regulation VREF(LR) VCC = 11.5 V ~ 28 V COMP Pin Source Current 1 ICOMP(SRC)1 VFB = 2.4 V 3–6 − 22 − 11 −1 µA COMP Pin Sink Current 1 ICOMP(SNK)1 VFB = 2.6 V 3–6 1 11 22 µA COMP Pin Sink Current 2 ICOMP(SNK)2 VFB = 2.7 V Error Amplifier Transconductance gm Gain Zero Duty COMP Voltage VCOMP(ZD) 3–6 1–6 3–6 3–6 15 35 55 µA 60 100 140 µS 0.50 0.65 0.90 V Restart Time tRS 7–6 140 220 300 µs tON(RS) 7–6 0.5 1.7 2.9 µs ICT 2–6 − 165 − 150 − 135 µA ON Time in Restart Operation CT Pin Source Current CT Pin Threshold Voltage CT Pin Delay Time of Control Maximum Switching Frequency (1) VCT(OFF) VCOMP = 4.5V 2–6 2.60 2.75 2.90 V tDLY(PWM) VCOMP = 2.2V 2–6 − 120 220 ns 7–6 − 300 400 kHz fMAX Drive Output Output Voltage (High) VOH IOUT = –100 mA 7–6 10.0 12.0 13.5 V Output Voltage (low) VOL IOUT = 200 mA 7–6 0.40 0.75 1.25 V tr COUT = 1000 pF 7–6 − 60 120 ns tf COUT = 1000 pF 7–6 − 20 70 ns Output Rise Time Output Fall Time (2) (2) Zero Current Detection (1) (2) Design assurance item Shown in Figure 3-1 90% VOUT 10% tr tf Figure 3-1 Switching time SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 4 SSC2016S Parameter Zero Current Detection Threshold Voltage (High) Zero Current Detection Threshold Voltage (Low) Zero Current Detection Delay Time(1) ZCD Pin Clamp Voltage Pins Min. Typ. Max. Unit VZCD(H) 5–6 1.25 1.40 1.55 V VZCD(L) 5–6 0.60 0.70 0.80 V tDLY(ZCD) 5–6 − 70 160 ns 5–6 6.5 7.7 9.0 V VCS(OCP1) 4–6 0.475 0.500 0.525 V VCS(OCP2) 4–6 1.35 1.50 1.65 V tDLY(OCP) 4–6 90 215 340 ns ICS 4–6 − 40 − 20 − 10 µA VOVP 1–6 VOVP(HYS) 1–6 1.040 ×VREF 40 1.060 ×VREF 60 1.080 ×VREF 80 mV VUVP 1–6 200 300 400 mV VUVP(HYS) 1–6 70 110 150 mV Thermal Shutdown Threshold (1) Tj(TSD) – 135 150 – °C Thermal Shutdown Hysteresis (1) Tj(TSDHYS) – – 10 – °C θj-A – – – 180 °C/W Overcurrent Protection Function Overcurrent Protection Threshold Voltage 1 Overcurrent Protection Threshold Voltage 2 Overcurrent Protection Delay Time CS Pin Source Current FB Pin Protection Function Overvoltage Protection Threshold Voltage Overvoltage Protection Hysteresis Undervoltage Protection Threshold Voltage Undervoltage Protection Hysteresis Symbol VZCD(CL) Conditions IZCD=3mA V Thermal Shutdown Protection Thermal Resistance Junction to Ambient Resistance (1) (1) Design assurance item SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 5 SSC2016S 3. Block Diagram OVP 8 VCC REG 1.060V×VREF UVLO 8.5V/7.5V UVP TSD 300mV /410mV 7 OUT Error Amp. FB 1 R Q S VREF=2.500V RAMP OSC CT 2 6 GND Restart timer VCC Negative clamp COMP 3 5 ZCD fMAX limit OCP1 CS 4 Down edge det 0.500V 1.40V /0.70V OCP2 S Q Power on reset 1.50V R BD_SSC2016S_R5 4. Pin Configuration Definitions Number Name 1 FB GND 2 CT ZCD 3 COMP 4 CS 5 ZCD 6 GND Overcurrent Protection signal input Zero current detection signal input and bottom-on-timing adjustment Ground 7 OUT Gate drive output 8 VCC Power supply input for control circuit FB 1 8 VCC CT 2 7 OUT COMP 3 6 CS 4 5 Function Feedback signal input, Overvoltage Protection signal input and FB pin Undervoltage Protection signal input Timing capacitor connection Phase compensation SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 6 SSC2016S 5. Typical Application DBYP BR1 DFW P VAC D1 T1 VOUT R2 Q1 D R3 C1 R4 C2 RVS1 R1 RCS LINE GND R5 U1 C5 ZCD CS 6 C7 7 External power supply 8 NC 5 C6 GND COMP OUT CT VCC FB 4 RS CS 3 CP 2 C4 1 C3 SSC2016S RVS2 TC_SSC2016S_1_R2 Figure 5-1 Power supply from external power supply DBYP BR1 DFW P VAC D1 T1 VOUT R2 Q1 D R3 C1 RST R4 C2 RVS1 RCS LINE GND R5 R1 U1 ZCD RZ C6 6 NC 5 C5 CS GND COMP OUT CT 4 CCP 7 DVCC DZVCC CVCC C7 8 VCC FB SSC2016S RS CS 3 CP 2 C4 1 C3 RVS2 TC_SSC2016S_2_R2 Figure 5-2 Power supply from an auxiliary winding SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 7 SSC2016S 6. External Dimensions 6.0±0.2 3.9±0.2 SOIC8 0 ～ 10° 0.605 TYP 0.15±0.05 1.5±0.05 5.02±0.2 1.27 0.60±0.2 0.4±0.05 0.15 NOTES: 1) All liner dimensions are in millimeters 2) Pb-free. Device composition compliant with the RoHS directive. 7. Marking Diagram 8 SC2016 SKYMD 1 Part Number Lot Number Y is the last digit of the year (0 to 9) M is the month (1 to 9,O,N or D) D is a period of days 1 : 1st to 10th 2 : 11th to 20th 3 : 21st to 31st Sanken Control Number SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 8 SSC2016S 8. Operational Description All of the parameter values used in these descriptions are typical values, unless they are specified as minimum or maximum. With regard to current direction, "+" indicates sink current (toward the IC) and "–" indicates source current (from the IC). 8.1 Critical Conduction Mode: CRM Figure 8-1 and Figure 8-2 show the PFC circuit and CRM operation waveform. The IC performs the on/off operation of switching device Q1 in critical mode (the inductor current is zero). Thus, the low drain current variation di/dt of power MOSFET is accomplished. Also, adjusting the turn-on timing at the bottom point of VDS free oscillation waveform (quasi-resonant operation), low noise and high efficiency PFC circuit is realized. Reference VREF = 2.500 V by using error amplifier (Error AMP) connected to FB pin. The output of the Error AMP is averaged and the phase is compensated. This signal VCOMP is compared with the ramp signal VOSC to achieve the on-time control. The on-time becomes almost constant in commercial cycle by setting VCOMP to respond below 20 Hz (Figure 8-4). This is achieved by tuning the capacitor connected to COMP pin. The off-time is set by detecting the zero current signal of boost winding P. The zero current is detected by auxiliary winding D and ZCD pin. DFW T1 P VOUT RVS1 D U1 Error AMP Q1 PWM COMP 7 OUT FB 1 VCOMP Q R S 2.500V VSET C3 VOSC ZCD 1.40 V OSC ZCD 5 R1 Q1 C1 VAC IOFF CT 2 RS GND 6 CP C2 D S COMP RCS /0.70 V DFW T1 RVS2 3 C6 C4 CS ION Figure 8-3 CRM control circuit √2×VACRMS Figure 8-1 PFC circuit VAC(t) ILPEAK IL(t) IL=ION+IOFF ILPEAK √2×IACRMS IAC(t) 1 I L ( AVG ) ILPEAK 2 ION tON tOFF IOFF VCOMP VOSC Bottom on Free oscillation VSET OUT pin voltage Q1 VDS OFF ON OFF ON Turn on delay time VAC(t) ILPEAK(t) IL(AVG.)(t) Figure 8-2 CRM operation and bottom on operation Figure 8-4 CRM operation waveforms Figure 8-3 shows the internal CRM control circuit. The power MOSFET Q1 starts switching operation by self-oscillation. The on-time control is as follows: the detection voltage RVS2 is compared with the Feedback Voltage SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 9 SSC2016S The off duty DOFF of boost converter in CRM mode have the relation of DOFF(t) = VAC(t)/VOUT and is proportional to input voltage, where V AC(t) is the input voltage of AC line as a function of time. As a result of aforementioned control shown in Figure 8-4, the peak current ILPEAK of the inductance current IL becomes sinusoidal. Since the averaged input current become similar to AC input voltage waveform by Low Pass Filter at input stage, high power factor is achieved. VCC（OFF） 8.2 VCC（ON） VCC pin voltage Startup Operation Figure 8-5 and Figure 8-7 show the VCC pin peripheral circuit. Figure 8-5 shows how to use an external power supply. Figure 8-7 shows how to use an auxiliary winding. 8.2.1 Startup Stop ICC To Use an External Power Supply When an external power supply shown in Figure 8-5 is used, the startup operation is as follows. As shown in Figure 8-6, when VCC pin voltage rises to the Operation Start Voltage VCC(ON) = 8.5 V, the control circuit starts operation and the COMP pin voltage increases. The COMP pin voltage increases to the Zero Duty COMP Voltage VCOMP(ZD) = 0.65 V, switching operation starts. When the VCC pin voltage decreases to VCC(OFF) = 7.5 V, the control circuit stops operation by Undervoltage Lockout (UVLO) circuit, and reverts to the state before startup. Since the COMP pin voltage rises from zero during startup period, the VCOMP signal shown in Figure 8-3 gradually rises from low voltage. The on-width gradually increased to restrict the rise of output power by the Softstart Function. Thus, the stress of the peripheral component is reduced. U1 8 VCC External power supply C7 3 RS CS CP COMP GND 6 Figure 8-6 Relationship between VCC pin voltage and ICC 8.2.2 To Use an Auxiliary Winding When an auxiliary winding is used as shown in Figure 8-7, CVCC is charged through RST at startup. When VCC pin voltage rises to VCC(ON) = 8.5 V, the control circuit starts operation. Figure 8-8 shows the VCC pin voltage behavior during startup period. When the VCC pin voltage reaches VCC(ON), the control circuit starts operation. Then the circuit current increases and the VCC pin voltage decreases. At the same time, the auxiliary winding voltage VD increases in proportion to the output voltage. These are all balanced to produce VCC pin voltage. The value of CVCC, the turns ratio of boost winding P and auxiliary winding D should be set so that VCC pin voltage is maintained higher than VCC(OFF)(Refer to Section 9.1.2). If the values of RST and CVCC are large, the startup time becomes longer. Adjustment is necessary in actual operation. When the COMP pin voltage increases to the Zero Duty COMP Voltage VCOMP(ZD) = 0.65 V after the control circuit starts operation, switching operation starts and the circuit current is supplied from auxiliary winding D as follows. VB and VD are the voltage of auxiliary winding during Q1 on and off, respectively. When Q1 is on, CCP is charged by VB. When Q1 is off, the capacitor connected to VCC pin, CVCC, is charged by VD + VB (=VCCP). VB is calculated using Equation (1). VB VIN Figure 8-5 VCC pin peripheral circuit (Power supply from external power supply) ND (V) NP (1) Where VIN: C1 voltage (V) NP: Number of turns of boost winding P (turns) ND: Number of turns of auxiliary winding D (turns) SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 10 SSC2016S 8.4 VAC VOUT T1 P C1 DFW Q1 RST VIN t ON ( MAX ) RCS RZ LINE GND 8 CVCC U1 DVCC DZVCC 6 8.5 Figure 8-7 VCC pin peripheral circuit (Power supply from auxiliary winding) VCC IC startup VCC(ON) Startup success Target Operating Voltage Increased by output voltage rising VCC(OFF) Startup failure Time Figure 8-8 VCC during startup period 8.3 C4 VCT ( OFF ) I CT (s) (2) where C4: Capacitance of capacitor connected to CT pin (μF) VCT(OFF): CT Pin Threshold Voltage (V) ICT: CT Pin Source Current (μA) CCP VCCP GND In order to reduce audible noise of transformer at transient state, the Maximum on-time, tON(MAX), should be set. The tON(MAX) depends on the value of C4 connected to CT pin, and is calculated by Equation (2). D VD VB VCC Maximum On-time Setting Restart Circuit The IC is self-oscillation type. The off-time of OUT pin is set by the detecting zero current signal at ZCD pin. When the off-time of OUT pin is maintained for tRS = 220 μs or more, the restart circuit is activated and OUT pin turns on. The ON time of the OUT pin is tON(RS) = 1.7 μs in the restart operation. At intermittent oscillation period in startup and light load, the restart circuit is activated and the switching operation is stabilized. Since tRS = 220 μs corresponds to the operational frequency of 6.25 kHz, the minimum frequency should be set to higher than 20 kHz (above audible frequency) at the inductance value design. Zero Current Detection and Bottom-on Timing Setting Figure 8-9 shows the peripheral circuit of ZCD pin, Figure 8-10 shows the zero current detection waveform. The off-time is determined by detecting the zero current of the boost winding P via the auxiliary winding D and ZCD pin The polarity of winding P and winding D of transformer T1 are shown in Figure 8-9. When the OUT pin voltage becomes low and the power MOSFET turns off, the ZCD pin voltage becomes the voltage of auxiliary winding D as shown in Figure 8-10. After the turning off of the power MOSFET, when ZCD pin voltage is above VZCD(H) = 1.40 V, OUT pin voltage is kept to be Low. When ZCD pin voltage becomes below VZCD(L) = 0.70 V, OUT pin voltage becomes High and power MOSFET turns on. After the turning off of the power MOSFET, when the current in boost winding become zero, VDS waveform starts free oscillation based on the inductance LP, the output capacitance of power MOSFET COSS and the parasitic capacitance. The bottom point of VDS is calculated as follows: t HFP ≒ L P C V (s) (3) where tHFP: Half cycle of free oscillation (s) LP: Inductance of boost winding (H) CV: Combined output capacitance of power MOSFET COSS and parasitic capacitanc (F) In order to set the timing of turn on to the bottom point of VDS as shown in Figure 8-11, adjust the turn on delay time tHFP by using C6 and R1 in actual operation codition as shown in Figure 8-9. Since R1 have a role as the current limiting resistor of ZCD pin, adjust the C6 value if R1 value exceeds the range of limiting. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 11 SSC2016S 8.6 VP P DFW VOUT T1 C1 D Q1 VD R1 7 OUT RCS U1 1.40V /0.70V OSC ZCD 5 C6 CT GND 2 6 C4 Figure 8-9 ZCD pin peripheral circuit L H L H L Primary winding P voltage, VP 0 Auxiliary winding D voltage, VD 0 Turn-on point ZCD pin voltage VZCD(H) VZCD(L) In the CRM operation, the switching frequency of a power MOSFET is varied in a period of sinusoidal AC input voltage. The switching frequency is lowest in the peak of AC input voltage and is high as getting close to the bottom of it. In addition, when output load decreases, the switching frequency increases entirely. In order to reduce the switching loss, the IC has the Maximum Switching Frequency Limitation Function that limits the switching frequency to fMAX of 300 kHz. 8.7 OUT pin voltage Maximum Switching Frequency Limitation Function Overcurrent Protection (OCP) Figure 8-12 shows the CS pin peripheral circuit and internal circuit. The inductor current, I L is detected by the detection resistor, RCS. The detection voltage, VRCS, is fed into CS pin. As shown in Figure 8-12, the CS pin is connected to capacitor-resistor filter (R5 and C5). The IC has two Overcurrent Protection (OCP) threshold voltages. ● OCP1 When VRCS increases VCS(OCP1) = 0.500 V or more, the output of the OUT pin becomes Low by pulse-by-pulse. 0 Turn-on delay time Drain to Source voltage, VDS Drain current, ID Inductor current, IL Figure 8-10 Zero current detection waveform ● OCP2 OCP2 is activated by malfunctions such as the short of a boost diode, DFW. If the instantaneous large current flows to a power MOSFET and the CS pin voltage increases to VCS(OSP2) = 1.50 V or more and this operation continues seven times, the output of OUT pin is latched to low level. Releasing the latched state is done by turning off the input voltage and by dropping VCC pin voltage below VCC(OFF). D DFW T1 tDLY VOUT P Bottom-on Free oscillation 7 Q1 U1 C2 OUT OCP1 4 CS VCS(OCP1) = 0.500V R5 Proper delay time OCP2 RCS VRCS C5 VCS(OCP2) = 1.5V GND Delay time is short. Make R1 or C6 value larger. 6 Delay time is Long. Make R1 or C6 value smaller. Figure 8-11 VDS turn on timing Figure 8-12 The CS pin peripheral circuit and internal circuit. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 12 SSC2016S 8.8 Overvoltage Protection (OVP) 8.10 Thermal Shutdown (TSD) Figure 8-13 shows the waveforms of Overvoltage Protection (OVP) operation. When the FB pin voltage increase to Overvoltage Protection Threshold Voltage, VOVP, OUT pin voltage become Low immediately and the switching operation stops. As a result, the rise of output voltage is prevented. VOVP is 1.060 times the Feedback Voltage Reference, VREF = 2.500 V. When the cause of the overvoltage is removed and FB pin voltage decreases to VOVP − VOVP(HYS) the switching operation restarts. FB pin voltage VOVP VOVP(HYS) OUT pin voltage < Using External Power Supply > When the temperature of control circuit increases to Tj(TSD) = 150 °C or more, Thermal Shutdown (TSD) is activated and the IC stops switching operation. When the fault condition is removed and the temperature decreases to less than Tj(TSD) – Tj(TSDHYS), the IC returns to normal operation automatically. < Using Auxiliary Winding D for VCC supply > When TSD is activated and the IC stops switching operation, VCC pin voltage decreases to VCC(OFF) and the control circuit stops operation. After that, the IC reverts to the initial state by UVLO circuit, and the IC starts operation when VCC pin voltage increases to VCC(ON) by startup current. Thus the intermittent operation by UVLO is repeated in TSD state. When the fault condition is removed and the temperature decreases to less than Tj(TSD) – Tj(TSDHYS), the IC returns to normal operation automatically. Figure 8-13 OVP waveforms 9. 8.9 FB Pin Under Voltage Protection (FB_UVP) FB pin Under Voltage Protection (FB_UVP) is activated when the FB pin voltage is decreased by the malfunctions in feedback loop such as the open of RVS1, the short of RVS2, or the open of FB pin. Figure 8-14 shows the FB pin peripheral circuit and internal circuit. When the FB pin voltage is decreased to VUVP = 300 mV or less, the OUT pin output is turned-off immediately and switching operation stops. This prevents the rise of output voltage. When the cause of malfunction is removed and the FB pin voltage rises to VUVP + VUVP(HYS), the switching operation restarts. VOUT U1 Error AMP PWM COMP OVP UVP GND Inductor T1 consists of a boost winding P and auxiliary winding D. The winding P is used for boosting the voltage and winding D is used for off-timing detection. The calculation methods of winding P and winding D are as shown below. Since the following calculating formulas are approximated, the peak current and the frequency of operational waveforms may be different from the setting value at calculating. Eventually, the inductance value should be adjusted in actual operation. Apply proper design margin to temperature rise by core loss and copper loss. 1 RVS2 VREF = 2.500V VOSC Inductor Design RVS1 FB IFB 9.1 Design Notes C3 VOVP = 1.060×VREF VOVP(HYS) = 60mV VUVP = 300mV VUVP(HYS) = 110mV 6 Figure 8-14 The FB pin peripheral circuit and internal circuit. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 13 SSC2016S 9.1.1 Boost winding, P Inductance LP of PFC in CRM mode is calculated as follows: 1) Output Voltage, VOUT The output voltage VOUT of boost-converter should be set higher than peak value of input voltage as following equation: VOUT 2 VACRMS ( MAX ) VDIF (V) (4) where VACRMS(MAX): Maximum AC input voltage rms value (V) VDIF: Boost voltage (about 10V) (V) 2) Operational Frequency, fSW(SET) and Maximum On-time, tON(SET)MAX Determine fSW(SET) that is minimum operational frequency at the peak of the AC line waveform. The frequency becomes higher with lowering the input voltage. The frequency at the peak of the AC line waveform, fSW(SET) should be set more than frequency of 20 kHz. The tON(SET)MAX at fSW(SET) is calculated by Equation (5). The tON(MAX) described in “8.4 Maximmum on-time setting” should be set above tON(SET)MAX. t ON (SET ) MAX VOUT 2 VACRMS ( MIN ) f SW (SET ) VOUT (s) (5) 4) Inductor peak current, ILP ILP is peak current at the minimum of AC input voltage waveform. ILP calculated as follows: ILP 9.1.2 2 2 POUT VACRMS ( MIN ) Figure 9-1 shows the polarity of boost winding P and auxiliary winding D. Given the number of windings of each winding as NP and ND, the turn ratio ND/NP is set satisfying following conditions. The condition of ND/NP making ZCD pin voltage above VZCD(H) = 1.40 V after power MOSFET turns off is expressed as follows: VZCD( H ) ND N P VOUT 2 VACRMS ( MAX ) (H) (6) VOUT T1 P DFW D U1 Q1 OUT C1 2 (8) where NP: The number of turns of boost winding P (turns) ND: The number of turns of auxiliary winding D (turns) VOUT: Output voltage (V) VACRMS(MAX): Maximum AC input voltage rms value (turns) 3) Inductance, LP Substituting both minimum and maximum of AC input voltage to VACRMS, choose a smaller one as LP value. LP is calculated as follows: VACRMS VOUT 2 VACRMS 2 POUT f SW (SET ) VOUT (7) Auxiliary Winding, D where VOUT: Output voltage (V) VACRMS(MIN): Maximum AC input voltage rms value (V) LP (A) R1 5 C6 7 ZCD CT 2 GND 6 RCS C4 Figure 9-1 ZCD Peripheral circuit where VACRMS: Maximum or minimum AC input voltage rms value (V) POUT: Output Power (W) fSW(SET): Minimum operational frequency at the peak of the AC line waveform (kHz) (The operational frequency becomes lowest at the peak of the AC line waveform. fSW(SET) should be set above frequency of 20 kHz.) η: Efficiency of PFC (In general, the range of η is 0.90 to 0.97, depending on on-resistance of power MOSFET RDS(ON) and forward voltage drop of rectifier diode VF.) SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 14 SSC2016S When power supply of VCC pin is suplied from auxiliary winding as shown in Figure 9-2, the condition of ND/NP is necessary to satisfy both Equation (8) and following Equation (12). VAC DFW T1 P C1 VIN VFFW RCS RZ VFVCC VCC 8 CVCC U1 GND N VIN D NP D VD VB 6 10(V) + VFZVCC + VFVCC < VB + VD 10(V) + VFZVCC + VFVCC VOUT Q1 RST From Equaition (9), (10) and (11), LINE GND CCP ND VOUT VIN VFFW NP ND VOUT VFFW NP DVCC DZVCC Assuming the value of VFZVCC and VFVCC are 1 V, VFZVCC 12(V) < Figure 9-2 VCC pin peripheral circuit (Power supply from auxiliary winding) Since the VFFW value is negligible compared with VOUT, ND/NP is expressed as follows: When switching operation starts, the current is supplied by auxiliary winding as follows: Auxiliary winding voltage in ON state and OFF state of Q1 are given as VB and VD, respectively. The forward voltages of Diode (DZVCC and DVCC) are given as VFZVCC and VFVCC. When Q1 is in ON state, CCP is charged by VB‐VFZVCC . When Q1 is in OFF state, the capacitor connected to VCC pin, CVCC is supplied by the voltage of (VB - VFZVCC ) + ( VD - VFVCC ) . Recommended operating range of VCC pin voltage is 10 V to 26 V. The maximum VCC pin input voltage is limited by the zener voltage of DZVCC. Since the minimum VCC pin input voltage must be set higher than 10 V of Recommended operating range, it is expressed as follows: 10(V) < (VB - VFZVCC ) + (VD - VFVCC ) ND (V + VFFW ) N P OUT N D 12(V) > N P VOUT (12) (9) Gigen the C1 voltage is VIN, VB and VD are expressed as follows: VB VIN VD ND (V) NP ND VOUT VIN VFFW (V) NP (10) (11) where VFFW: Forwerd voltage of DFW (V) SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 15 SSC2016S 9.2 External Components Take care to use properly rated, including derating as necessary and proper type of components. Figure 9-3 shows the IC peripheral circuit. DBYP DFW P D1 T1 VOUT R2 Q1 D R3 C1 R4 C2 according to output power. The typical value of CS and RS are 1 μF and 68 kΩ, respectively. When CS value is too large, the response becomes slow at dynamic variation of output and the output voltage decreases. Since CS and RS affect on the soft-start period at startup, adjustment is necessary in actual operation. The ripple of output detection signal is averaged by CP. When the CP value is too small, the IC operation may become unstable due to the output ripple. The value of capacitor CP is approximately 1 μF. R1 RCS LINE GND 9.2.3 R5 CT Pin Peripheral Circuit, C4 U1 C5 ZCD 5 6 C7 External power supply 7 8 NC C6 CS GND COMP OUT CT VCC FB SSC2016S 4 RS C4 in Figure 9-3 is a capacitor for the maximum on time setting. Refer to Section 8.4 for C4 setting. CS RVS1 3 CP 2 C4 9.2.4 1 C3 Figure 9-3 The IC peripheral circuit. 9.2.1 FB Pin Peripheral Circuit (Output VoltageDetection) The output voltage VOUT is set using RVS1 and RVS2. It is expressed by the following formula: V VOUT REF I FB R VS1 VREF (V) R VS 2 (13) where VREF: Feedback Voltage Reference = 2.500 V IFB: FB sink current= 0.7 µA RVS1, RVS2: Combined resistance to set VOUT (Ω) Since RVS1 have applied high voltage and have high resistance value, RVS1 should be selected from resistors designed against electromigration or use a combination of resistors for that. The value of capacitor C3 between FB pin and GND pin is set approximately 100 pF to 0.01 μF, in order to reduce the switching noise. 9.2.2 CS Pin Peripheral Circuit, RCS, R5 and C5 RVS2 COMP Pin Peripheral Circuit, RS, CS and CP The FB pin voltage is induced into internal Error AMP. The output voltage of the Error AMP is averaged by the COMP pin. The on-time control is achieved by comparing the signal VCOMP and the ramp signal VOSC. CS and RS adjust the response speed of changing on-time RCS shown in Figure 9-3 is current sensing resistor. RCS is the resistor for the current detection. A high frequency switching current flows to RCS, and may cause poor operation if a high inductance resistor is used. Choose a low inductance and high surge-tolerant type. RCS is calculated using the following Equation (14), where Overcurrent Protection Threshold Voltage VCS(OCP) is 0.500 V and ILP is calculated using Equation (7). R CS VCS( OCP ) I LP (Ω) (14) The loss PRCS at RCS is calculated by Equation (16) using Equation (15). I DRMS＝ 2 2 POUT VACRMS ( MIN ) 1 4 2 VACRMS(MIN) － 6 9 π VOUT PRCS I DRMS R CS 2 (W) (A) (15) (16) Where IDRMS: RMS Drain current (A) VACRMS(MIN): Minimum AC input voltage rms value (V) VOUT: Output voltage (V) POUT: Output power (W) η: Efficiency of PFC SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 16 SSC2016S The CR filter (R5 and C5) is connected to CS pin. CR filter (R5 and C5) prevents IC from responding to the drain current surge at MOSFET turn-on and avoids the unstable operation of the IC. R5 value of approximately 47 Ω is recommended, since the CS Pin Source Current affects the accuracy of OCP detection. C5 value is reccommended to be calculated by using following formula in which cut-off frequency of CR filter (C5 and R5) is approximately 0.5 MHz to 3.0MHz. C5 1 (F) 2 π110 6 R 5 (17) If R5 value is 47 Ω, C5 value is approximately 1000 pF to 6800 pF. C5 value should adjust based on actual operation in application. 9.2.5 ZCD Pin Peripheral Circuit, R1 and C6 R1 is for the limiting of the input and output current to ZCD pin. The value of resistor R1 is determined so that the ZCD pin current is smaller than the absolute maximum rating. The recommended value of ZCD pin current is less than 3 mA. The R1 value is chosen to satisfy both Equation (18) and Equation (19). In addition, the bottom-on timing is set by C6 and R1 (Refer to Section 8.5). 1) Limiting of ZCD pin source current (at Q1 ON state) 9.2.6 OUT Pin Peripheral Circuit (Gate Drive Circuit) The OUT pin is the gate drive output that can drive the external power MOSFET directly. The maximum output voltage of OUT pin is the VCC pin voltage. The maximum current is −500 mA for source and 1000 mA for sink, respectively. R3 is for source current limiting. Both R2 and D1 are for sink current limiting. The values of these components are adjusted to decrease the ringing of Gate pin voltage and the EMI noise. The reference value is several ohms to several dozen ohms. R4 is used to prevent malfunctions due to steep dv/dt at turn-off of the power MOSFET, and the resistor is connected near the MOSFET, between the gate and source. The reference value of R4 is from 10 kΩ to 100 kΩ. R2, R3, D1 and R4 are affected by the printed circuit board trace layout and the power MOSFET capacitance. Thus, the optimal values should be adjusted under actual operation of the application. 9.2.7 VCC Pin Peripheral Circuit < Using External Power Supply > Figure 9-4 shows the VCC pin peripheral circuit. The value of capacitor C7 is set approximately 1000 pF, in order to reduce the switching noise. 8 External power supply 3 C7 N 2 VACRMS ( MAX ) D NP R1 3 3 10 (A) (Ω) 2) Limiting of ZCD pin sink current (at Q1 OFF state) ND VZCD( CL ) NP 3 10 3 (A) VOUT R1 (Ω) (19) Where VOUT: Output voltage (V) NP: The number of turns of boost winding P (turns) ND: The number of turns of auxiliary winding D (turns) VZCD(CL): ZCD Pin Clamp Voltage (7.7 V) COMP CP GND 6 CS (18) Where VACRMS(MAX): Maximum AC input voltage rms value (V) NP: The number of turns of boost winding P (turns) ND: The number of turns of auxiliary winding D (turns) RS U1 VCC Figure 9-4 VCC pin peripheral circuit (Power supply from external power supply) < Using Auxiliary Winding D for VCC supply > Figure 9-5 shows the VCC pin peripheral circuit when VCC pin is supplied from auxiliary winding. ● RST The value of startup resistor, RST is selected so that the current more than ICC(OFF) = 100 µA (max.) can be supplied to VCC pin at startup.RST is expressed as follows: R ST 2 VACRMS ( MIN ) VCC( ON )( MAX ) I CC( OFF )( MAX ) (Ω) (20) Where VACRMS(MIN): Minimum AC input voltage rms value (V) SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 17 SSC2016S When the specification of AC input voltage is 100 V or Universal, the value of RST is approximately 100 kΩ to 220 kΩ. When the specification of AC input voltage is 230 V, the value of RST is approximately 180 kΩ to 330 kΩ. The rating of RST is chosen taking into account the loss of RST at maximum input voltage. Since the high voltage is applied to resistor, choose a resistor designed against electromigration or use a series combination of resistors. 9.2.8 Power MOSFET, Q1 Choose a power MOSFET having proper margin of VDSS against output voltage, VOUT. The size of heat sink is chosen taking into account some loss by switching and ON resistance of MOSFET. The loss PRDS(ON) by on-resistance, RDS(ON) of power MOSFET is calculated using IDRMS of the result of Equation (15) as follows: PRDS (ON ) IDRSM R DS (ON )125 C (W) 2 ● CVCC The approximate startup time is determined by the value of CVCC. It is calculated as follows where the initial voltage of VCC pin is zero. t START ≒ C7 VCC ( ON ) (s) 2 VACRMS VCC ( ON ) (21) I CC ( OFF ) R ST In general, power supply applications, CVCC, is approximately 22 µF to 47 µF. ● RZ, CCP and DZVCC The circuit consists of RZ, CCP and RZ is the boost circuit of VCC pin. RZ is the limiting resistor for the breakdown current of DZVCC. The RZ value is approximately 150 Ω. CCP is charged when Q1 is in ON state. The CCP value is approximately 22 nF. Since the absolute maximum rating value of VCC pin is 28 V, the zener voltage of DZVCC is chosen to be less than it. ● C7 If CVCC and the VCC pin are distant from each other, a capacitor C7 should be placed as close as possible to the VCC pin. C7 is approximately 1000 pF, in order to reduce the switching noise. VAC 9.2.9 resistance of MOSFET at Boost Diode, DFW Choose a boost diode having proper margin of a peak reverse voltage VRSM against output voltage VOUT. A fast recovery diode is recommended to reduce the switching noise and loss. Please ask our staff about our lineup. The size of heat sink is chosen taking into account some loss by VF and recovery current of boost diode. The loss of VF, PDFW is expressed as follows: P DFW VF I OUT (W) (23) Where VF: Forward voltage of boost diode (V) IOUT: Out put current (A) 9.2.10 Bypass Diode, DBYP Bypass diode protects the boost diode from a large current such as an inrush current. A high surge current tolerance diode is recommended. Please ask our staff about our lineup. VOUT T1 P C1 Where RDS(ON)125°C: ON Tch = 125 °C (Ω) (22) DFW Q1 RST D VD VB RCS RZ LINE GND CCP VCCP VCC 8 DVCC DZVCC U1 C7 CVCC GND 6 Figure 9-5 VCC pin peripheral circuit (Power supply from auxiliary winding) SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 18 SSC2016S 9.2.11 Output Capacitor, C2 9.3 Apply proper design margin to accommodate the ripple current, the ripple voltage and the temperature rise. Use of high ripple current and low impedance types, designed for switch-mode power supplies, is recommended, depending on their purposes. In order to obtain C2 value CO, calculate both Equation (24) and (26) described in following and select a larger value. PCB Trace Layout and Component Placement Since the PCB traces design and the component layout significantly affects operation, EMI noise, and power dissipation, the high frequency PCB trace should be low impedance with small loop and wide trace. In addition, the ground traces affect radiated EMI noise, and wide, short traces should be taken into account. Figure 9-6 shows the circuit design example. 1) Ripple voltage considered I OUT CO (F) 2 f LINE VOUT ( RI ) (24) Where VOUTRIPPLE: C2 ripple voltage (10 VPP for example) fLINE: Line frequency (Hz) IOUT: Output current (A) The C2 voltage is expressed Equation (25). When the output ripple is high, the VC2 voltage may reach to Overvoltage Protection voltage, VOVP in near the maximum value of VC2, or input current waveform may be distorted due to the stop of the boost operation in near the minmum value of VC2. It is necessary to select large CO value or change the setting of output voltage (boost voltage). VC 2 VOUT VOUT ( RI ) 2 (V) (25) 2) Output hold time considered CO 2 POUT t HOLD VOUT VOUT ( MIN ) 2 2 (F) (26) 1) Main Circuit Trace This is the main trace containing switching currents, and thus it should be as wide trace and small loop as possible. 2) Control Ground Trace Layout Since the operation of IC may be affected from the large current of the main trace that flows in control ground trace, the control ground trace should be separated from main trace and connected at a single point grounding of point A in Figure 9-6 as close to the RCS pin as possible. 3) RCS Trace Layout RCS should be placed as close as possible to the Source pin and the CS pin. The peripheral components of CS pin should be connected by dedicated pattern from root of RCS. The connection between the power ground of the main trace and the IC ground should be at a single point ground which is close to the base of RCS. 4) Peripheral Component of IC The components for control connected to the IC should be placed as close as possible to the IC, and should be connected as short as possible to the each pin. Where tHOLD: Output hold time (s) VOUT(MIN) : Minmum output voltage of C2 during output hold (V) If tHOLD = 20 ms, PO = 200 W, η = 90 % and the output voltage = 330 V to 390 V, CO value is derived as 205 μF. Thus, CO value of approximately 220 μF is connected. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 19 SSC2016S (1) Main trace should be wide trace and small loop DBYP BR1 DFW P VOUT VAC T1 D1 R2 D Q1 R3 C1 C2 R4 RCS (3)RCS Should be as close to Source pin as possible. (3) Connected by dedicated pattern from root of RCS (2) Control GND trace should be connected at a single point as close to the RCS as possible R1 U1 ZCD 6 C7 7 NC 5 C6 External power supply LINE GND A R5 CS GND COMP OUT CT VCC FB C5 4 RS 3 CP 2 C4 CS RVS1 8 1 SSC2016S C3 RVS2 (4)The components connected to the IC should be as close to the IC as possible, and should be connected as short as possible Figure 9-6 Example of connection of peripheral component SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 20 SSC2016S 10. Reference Design of Power Supply As an example, the following show the power supply specification, the circuit schematic, the bill of materials, and the transformer specification. ● Circuit schematic IC Input voltage Output power SSC2016S 85V AC to 265VAC 100 W (390V, 0.256 A) 45 kHz Minimum frequency ● Circuit schematic F1 L1 DB1 VAC D1 D2 C2 C1 VOUT P T1 C3 D R10 R13 R8 1 2 VCC FB U1 CT C5 R11 R12 4 C6 R1 7 NC COMP D3 8 OUT 3 R14 R9 SSC2016S C11 C12 C13 C4 DZ1 R16 R3 D4 Q1 6 GND R17 R5 5 CS R15 R18 R4 ZCD C8 C7 C9 R2 C10 R6 R7 LINE GND ● Bill of materials Symbol Ratings(1) Recommended Sanken Parts Symbol Ratings(1) Recommended Sanken Parts F1 Fuse, AC250 V, 4 A R1 68 kΩ L1 CM inductor, 12 mH R2 47 Ω (2) DB1 Bridge, 600 V, 4 A R3 10 Ω (2) D1 General, 600 V, 3 A RM 4A R4 100 Ω (2) D2 Fast recovery, 600 V, 5 A FMX-G16S R5 10 kΩ D3 Fast recovery, 200V, 1A AL01Z R6 0.18 Ω, 1 W D4 Schottky, 40 V, 1 A AK 04 R7 0.18 Ω, 1 W (2) C1 Film, 0.22 μF, 310 V R8 150 Ω (2) C2 Film, 0.22 μF, 310 V R9 47 kΩ C3 Ceramic, 0.82 μF, 450V R10 (3) Metal oxide, 220 kΩ, 1 W C4 Electrolytic, 120 μF, 450 V R11 22 kΩ, ± 1 % C5 Ceramic, 0.01 μF R12 (2) 2 kΩ, ± 1 % C6 Ceramic, 1000 pF R13 (3) 750 kΩ, ± 1 % C7 Ceramic, 0.47 μF R14 (3) 750 kΩ, ± 1 % C8 Ceramic, 1 μF R15 (3) 750 kΩ, ± 1 % C9 Ceramic, 3300 pF R16 (3) 750 kΩ, ± 1 % (2) C10 Ceramic, Open R17 (2)(3) 750 kΩ, ± 1 % C11 (2) Ceramic, Open R18 (2)(3) 30 kΩ, ± 1 % Power MOSFET, 600 V,10 A, < 0.75 Ω C12 Electrolytic, 47 μF, 35V Q1 C13 Ceramic, 22 nF T1 See the specification DZ1 Zener, 15 V U1 IC SSC2016S (1) Unless otherwise specified, the voltage rating of capacitor is 50 V or less and the power rating of resistor is 1/8 W or less. (2) It is necessary to be adjusted based on actual operation in the application. (3) Resistors applied high DC voltage and of high resistance are recommended to select resistors designed against electromigration or use combinations of resistors in series for that to reduce each applied voltage, according to the requirement of the application. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 21 SSC2016S ● Transformer specification Primary inductance : 290 μH Core size : EER28 AL-Value : 92.5 nH/N2 Gap length : 1.2 mm (center gap) Winding specification Number of Location Symbol turns (turns) Primary winding P1 56 Auxiliary winding D 8 D Cross-section view Configuration Note φ 0.20 × 10 φ 0.32 Solenoid winding Solenoid winding Litz wire AC input VCC, ZCD P1 P1 Bobbin Wire (mm) D Drain GND ●mark shows the start point of winding SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 22 SSC2016S OPERATING PRECAUTIONS In the case that you use Sanken products or design your products by using Sanken products, the reliability largely depends on the degree of derating to be made to the rated values. Derating may be interpreted as a case that an operation range is set by derating the load from each rated value or surge voltage or noise is considered for derating in order to assure or improve the reliability. In general, derating factors include electric stresses such as electric voltage, electric current, electric power etc., environmental stresses such as ambient temperature, humidity etc. and thermal stress caused due to self-heating of semiconductor products. For these stresses, instantaneous values, maximum values and minimum values must be taken into consideration. In addition, it should be noted that since power devices or IC’s including power devices have large self-heating value, the degree of derating of junction temperature affects the reliability significantly. Because reliability can be affected adversely by improper storage environments and handling methods, please observe the following cautions. Cautions for Storage Ensure that storage conditions comply with the standard temperature (5 to 35°C) and the standard relative humidity (around 40 to 75%); avoid storage locations that experience extreme changes in temperature or humidity. Avoid locations where dust or harmful gases are present and avoid direct sunlight. Reinspect for rust on leads and solderability of the products that have been stored for a long time. Cautions for Testing and Handling When tests are carried out during inspection testing and other standard test periods, protect the products from power surges from the testing device, shorts between the product pins, and wrong connections. Ensure all test parameters are within the ratings specified by Sanken for the products. Soldering When soldering the products, please be sure to minimize the working time, within the following limits: • 260 ± 5 °C 10 ± 1 s (Flow, 2 times) • 380 ± 10 °C 3.5 ± 0.5 s (Soldering iron, 1 time) Electrostatic Discharge When handling the products, the operator must be grounded. Grounded wrist straps worn should have at least 1MΩ of resistance from the operator to ground to prevent shock hazard, and it should be placed near the operator. Workbenches where the products are handled should be grounded and be provided with conductive table and floor mats. When using measuring equipment such as a curve tracer, the equipment should be grounded. When soldering the products, the head of soldering irons or the solder bath must be grounded in order to prevent leak voltages generated by them from being applied to the products. The products should always be stored and transported in Sanken shipping containers or conductive containers, or be wrapped in aluminum foil. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 23 SSC2016S IMPORTANT NOTES The contents in this document are subject to changes, for improvement and other purposes, without notice. Make sure that this is the latest revision of the document before use. Application examples, operation examples and recommended examples described in this document are quoted for the sole purpose of reference for the use of the products herein and Sanken can assume no responsibility for any infringement of industrial property rights, intellectual property rights, life, body, property or any other rights of Sanken or any third party which may result from its use. Unless otherwise agreed in writing by Sanken, Sanken makes no warranties of any kind, whether express or implied, as to the products, including product merchantability, and fitness for a particular purpose and special environment, and the information, including its accuracy, usefulness, and reliability, included in this document. Although Sanken undertakes to enhance the quality and reliability of its products, the occurrence of failure and defect of semiconductor products at a certain rate is inevitable. Users of Sanken products are requested to take, at their own risk, preventative measures including safety design of the equipment or systems against any possible injury, death, fires or damages to the society due to device failure or malfunction. Sanken products listed in this document are designed and intended for the use as components in general purpose electronic equipment or apparatus (home appliances, office equipment, telecommunication equipment, measuring equipment, etc.). When considering the use of Sanken products in the applications where higher reliability is required (transportation equipment and its control systems, traffic signal control systems or equipment, fire/crime alarm systems, various safety devices, etc.), and whenever long life expectancy is required even in general purpose electronic equipment or apparatus, please contact your nearest Sanken sales representative to discuss, prior to the use of the products herein. The use of Sanken products without the written consent of Sanken in the applications where extremely high reliability is required (aerospace equipment, nuclear power control systems, life support systems, etc.) is strictly prohibited. When using the products specified herein by either (i) combining other products or materials therewith or (ii) physically, chemically or otherwise processing or treating the products, please duly consider all possible risks that may result from all such uses in advance and proceed therewith at your own responsibility. Anti radioactive ray design is not considered for the products listed herein. Sanken assumes no responsibility for any troubles, such as dropping products caused during transportation out of Sanken’s distribution network. The contents in this document must not be transcribed or copied without Sanken’s written consent. SSC2016S - DSJ Rev.1.1 SANKEN ELECTRIC CO.,LTD. Mar. 02, 2016 http://www.sanken-ele.co.jp/en/ © SANKEN ELECTRIC CO.,LTD. 2015 24