ISL6745EVAL2Z Offline High Brightness White LED Driver With High Power Factor for Universal Input ® Application Note June 9, 2009 AN1411.3 Introduction The ISL6745UEVAL2Z utilizes Intersil’s double-ended voltage mode PWM controller for a SEPIC converter application requiring a constant output current. It consists of separate assemblies for the driver and for the LED board, which supports as many as 21 high brightness LEDs. The LED driver board converts a universal (85V to 275VAC) AC input to a DC output rated at 300mA. The design can be further optimized for applications that do not require universal AC input. ISL6745LEVAL2Z is for 80V to 140V applications. Worldwide, on average, 19% of the electric power goes for lighting [11]. In 2000, about 567BKWH of electric energy (or 16% of the nation’s electric energy in the United States) is for residential, commercial or industrial lighting [22], [3]33. The commonly used lighting technologies include incandescent and halogen bulbs, fluorescent and compact fluorescent lamps (CFL), and high intensity discharge (HID) lamps. Generally, the efficiency of the lighting sources is indexed by efficacy, or lumen per watt weighted to the sensitivity of the human eye. The efficacy of typical energy saving CFL lamps is around 7%~8%, compared with 2% for the conventional the incandescent bulbs [4]. With the advancement of new materials and manufacturing processes, the economics and performance of high brightness LEDs are now attracting the attention of academia and industry. For instance, in 2006, Cree Inc. demonstrated a prototype with a record white LED luminous efficacy of 131 lm/W [5]. Compared with commonly used lighting sources, white LEDs provide equivalent or superior efficacy, and improvements are announced frequently. Unlike the CFLs, LEDs contains no mercury, and are less susceptible to breakage. They have a very long expected life (100,000 hours, more than 10x as much as CFLs), and high on/off repetition capability. Of particular interest, they are easy to power when compared to many traditional sources. The practical application of LED lighting for commercial and residential applications has become a reality. The typical operating current of the high brightness LED is about 300mA~1000mA. The typical drive voltage for high brightness white LED is about 2.5V to 4V. The ISL6745UEVAL2Z evaluation board is a reference design for powering high brightness white LEDs. It utilizes the ISL6745 voltage mode PWM controller in the single-ended primary inductance converter (SEPIC) topology to convert a universal ac input to a variable 300mA DC output. See Figure 1. This application note describes the circuit operation design constraints, description of the evaluation board, and its performance. 1 FIGURE 1. TOP VIEW OF DRIVE AND LED BOARDS Key Features • Universal AC Input • Dimmable LED Brightness • High Power Factor • Overvoltage Protection • Overcurrent Protection • Transformerless Specifications for ISL6745UEVAL2Z • Input AC Voltage . . . . . . . . 85V to 275VAC (50Hz~60Hz) • Outputs DC . . . . . . . . . . . . . . . . . . . . . . . . . Up to 300mA • Output DC Voltage Ripple . . . . . . . . . . . . . . . . . . . . . . 5% • Typical Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75% • Typical Power Factor . . . . . . . . . . . . . . . . . . . . . . . . >0.95 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2008, 2009. All Rights Reserved All other trademarks mentioned are the property of their respective owners. Application Note 1411 Operation Mechanism and Design Constraints A simplified offline SEPIC converter for LED lighting applications is shown in Figure 3, where the voltage across C1 is the rectified AC voltage. A current sense resistor is placed in series with the switch S1. A second resistor is placed in series with the LED string to sense the load current. The control signals include the load current and switch current. The output voltage is sensed for the purpose of output overvoltage protection (OVP). Since the input capacitor C1 is very small, the voltage waveform is the rectified input voltage, and the voltage applied to the SEPIC converter is approximately a rectified sinusoidal. To achieve high power factor, the envelope of the converter input current must track the rectified input voltage waveform. This is accomplished when the converter is operated at a constant switching frequency, a constant duty ratio, and while operating in the discontinuous conduction mode (DCM). Assuming the impedance of the power source is negligible, the voltage across C1 is given in Equation 1, where subscript I denotes input AC line, and Vl is the amplitude of the input AC voltage with frequency ωl. v C1 ( t ) = V l sin ( ω l t ) GATE IL 1 IL 2 IQ ID FIGURE 2. TYPICAL OPERATION WAVEFORMS (EQ. 1) C2 L1 If the switching frequency of the converter is much higher than the utility frequency, and C2 is properly sized, the voltage across C2 will be equal to the voltage across C1. A feedback voltage, Vm, is created by the error amplifier. Vm is the amplified difference between the LED current, Io, and the reference voltage, Ir. Varying the reference voltage causes a proportional change in the LED brightness. The current signal from the current sense resistor, Rcs, which is connected in series with the boost switch S1, is compared with the overcurrent threshold for overcurrent protection. A sawtooth carrier signal is compared with the feedback signal Vm and generates the PWM signal to control the turn on/off of the switch. Typical waveforms of the inductor current, switch and diode currents are shown in Figure 2. D5 AC C1 C0 L2 S1 Rcs Rs D1~D4 O CP PW M Cs C FB - PW M CONTROLLER I ADJ + V ERR vo + OVP FIGURE 3. SEPIC CONVERTER FOR LED LIGHTING TABLE 1. SEPIC CONVERTER NAME AC 85V ~ 265VAC, 50Hz ~ 60Hz D1 ~ D4 Bridge Rectifier C1 Input Capacitor L1/L2 SEPIC Inductors S1 High Voltage MOSFET CO Output Capacitor C2 Intermediate Capacitor RS Current Sense Resistor PWM 2 DESCRIPTION ISL6745A PWM Controller AN1411.3 June 9, 2009 Application Note 1411 TABLE 1. SEPIC CONVERTER (Continued) NAME v C1 vO ⎞ ⎛ i L1 ( 1 ) = ⎜ i L1(0) + ---------- t ON – ------- t d⎟ L1 L1 ⎠ ⎝ v C1 vO ⎞ ⎛ i L2 ( 1 ) = ⎜ i L1(0) + ---------- t ON – ------- t d⎟ L2 L1 ⎠ ⎝ DESCRIPTION CF Feedback Capacitor IADJ Brightness Dimming Control CS The MOSFET Current D5 Output Diode where, the diode conducting time, td, is determined by the volt-second balance of the inductors, where Vl is the amplitude of the AC line voltage. t ON t d = ---------- V l sin ω l t VO There are three stages of operations: 1. The switch turns on, Diode is off. 3. Both switch and diode are off. During each switching period, the following circuit equations can be derived. SWITCH S1 TURNS ON At the beginning of the cycle, when switch S1 turns on, the free-wheeling current in L1 is IL1(0) and the voltage across the input inductor L1 is VC1. The freewheeling current in L1 is IL1(0). The voltage applied to the input inductor L1 is VC1. Since the voltage across C2 equals VC1, the same voltage is applied to L2. The inductor currents are given in Equation 2, where 0 denote the initial condition of the state variables. The switch current is the sum of the two inductor currents, and is given in Equation 3. This stage ends at tON. (EQ. 2) v C1 i L2 ( t ) = – i L1(0) + ---------- t L2 ⎛ v C1 v C1⎞ i Q ( t ) = i L1(t) + i L2(t) = ⎜ ---------- + ----------⎟ t L2 ⎠ ⎝ L1 (EQ. 3) DIODE D5 CONDUCTS The voltage applied to inductor L1 is –Vo, the same as inductor L2. The current in L1 decays according to Equation 4. The current in L2 decays and reverses. This stage ends when iL1 equals -iL2. The diode current is the sum of both the inductor currents. The currents are given in Equation 5, where tON is the interval when the switch is on. v C1 ⎛ v O⎞ ⎞ ⎛ i L1 ( t ) = ⎜ i L1(0) + ---------- t ON – ⎜ -------⎟ t⎟ L ⎝ L1⎠ ⎠ ⎝ 1 1 (EQ. 8) Therefore, the duty ratio of the PWM is expressed in Equation 9. VO d < -------------------VO + Vl (EQ. 9) Averaging this diode current in one switching cycle gives the average output current IO(t) during that switching cycle. t 1 s 1 ( t ON V 1 sin ( ω 1 t ) )2 i O ( t ) = ---- t i D ( t )dt = ------------------ ---------------------------------------------2t s V O ts 0 L 1 || L 2 ∫ (EQ. 10) Averaging the IO(t) over one line period, yields the average current of the output, since the average output capacitor current is zero. Therefore, the output current equals the average diode current. The output current also equals the average current in inductor L2, since the average current in C2 is zero. Therefore, the dominate ripple frequency is twice the line frequency as expressed in Equation 11. 2 2 t 1 1 1 d ts V1 i O = ---- I O ( t )dt = ------------------ ---------------------t1 0 L 1 || L 2 4V O ∫ (EQ. 11) The constraints for selecting the inductors are expressed in Equation 12: ⎛ V 1 ⎞2 L 1 || L 2 < ⎜ ---------------------⎟ ⎝ V O + V 1⎠ ts VO ------------4I O (EQ. 12) As can be seen, the maximum ripple current in the input inductor L1 occurs at the peaks of the input voltages as expressed in Equation 13. (EQ. 5) 2 DIODE D5 AND SWITCH S1 BLOCKING This is the freewheeling period of both inductors L1 and L2. The freewheeling currents are given in Equation 6. 3 t s ≥ t ON + t d (EQ. 4) v C1 vO ⎞ ⎛ i L2 ( t ) = ⎜ i L1(0) + ---------- t ON – ------- t⎟ L1 L1 ⎠ ⎝ 1 1 i D ( t ) = ( v C1 t ON – V O t ) ⎛ ------ + ------⎞ ⎝L L ⎠ (EQ. 7) To ensure the converter operates in DCM, the freewheeling time should be greater than or equal to zero as expressed in Equation 8. 2. The switch turns off, the diode is on. v C1 i L1 ( t ) = i L1(0) + ---------- t L1 (EQ. 6) t ON V 1 I 1rp = ----------------L1 (EQ. 13) Since, we assume unity power factor, and assume the power conversion efficiency is η as shown in Equation 14. 1 --- V 1 I 1 η = V O I O 2 (EQ. 14) AN1411.3 June 9, 2009 Application Note 1411 If we define the ripple factor Krpi = Irp/Il, where Il is the peak of the input current, then the constraint for DCM operation of the converter is as expressed in Equation 15. t ON ( V 1 )2 η t ON V 1 t ON V 1 L 1 > ----------------- = ----------------- = -----------------------------I rp K rp I 1 2K rp V O I O (EQ. 15) ⎛ V 1 + V O 2 4I O 2K rp V O I O⎞– 1 -⎟ L 2 < ⎜ --------------------- ------------- – --------------------------V1 t s V O t ON V 12 η ⎠ ⎝ 1 ω C = -------------RC fo In the above analysis, it is assumed that the voltage across the input capacitor C1 is independent of the circuit operation and follows the rectified input voltage closely. Furthermore, the voltage across C2 is identical to the voltage across C1. If the assumption is not correct, the current waveform will be distorted. The input capacitor can be estimated by using Equation 16. 2 4K rpi t s dp C 1 = ----------------------------K rpv V12 L 2 (EQ. 16) The AC source delivers power as a sine wave. Since the input is rectified, power is delivered to the load at twice the input line frequency. Therefore, the ripple frequency on the output voltage is also twice of the line frequency. To reduce the ripple, the output capacitor needs to be selected according to Equation 17. Vl Il C O > --------------------------------2V rp-p V O ω 1 sense resistor RS. By changing the current sense resistor, or the reference signal IADJ, the brightness of the LED can be dimmed. A Type I Error Amplifier is used as shown in Figure 3, with the crossover frequency determined by the feedback capacitor Cfb and the resistor R, given in Equation 18. (EQ. 17) The duty ratio is controlled by the difference between the reference signal IADJ and the voltage across the current (EQ. 18) The bandwidth should be less than the line frequency, so that the duty ratio of the converter does not disturb the sinusoidal power delivery from the source. Otherwise, harmonics appear in the input line current and degrade power factor. However, the bandwidth should be wide enough to allow adequate control of the load current. As a trade-off, the cut-off frequency can be around half of the line frequency. Overvoltage protection is needed to protect the LED and converter from damage. Due to the nonlinear relationship between the diode current and voltage, a small increase in output voltage can cause a large increase in current. The overvoltage protection is implemented by comparing the output voltage with a constant reference voltage, and the comparator output is used to control a small FET in parallel with the soft-start capacitor. Once the output voltage reaches the threshold, the FET is turned on, the soft-start capacitor discharged, and the duty cycle is reduced to zero. The PWM output is shutdown until the output voltage decays below the reset threshold. A new soft-start cycle begins at this time. This behavior repeats until the cause of the overvoltage is removed. Waveforms VINPUT VINPUT VINPUT VINPUT FIGURE 4. INPUT VOLTAGE AND CURRENT (VAC = 80V, IO = 30mA 4 FIGURE 5. INPUT VOLTAGE AND CURRENT, VAC = 120V, IO = 300mA AN1411.3 June 9, 2009 Application Note 1411 Waveforms (Continued) VINPUT RIPPLE VOUT VINPUT FIGURE 6. INPUT VOLTAGE AND CURRENT, VAC = 240V, IO = 300mA FIGURE 7. OUTPUT VOLTAGE AND RIPPLE IO = 100mA FIGURE 8. OUTPUT VOLTAGE AND RIPPLE Io = 300mA FIGURE 9. OUTPUT VOLTAGE AND RIPPLE Io = 200mA FIGURE 10. THE DRAIN-SOURCE VOLTAGE 5 AN1411.3 June 9, 2009 Application Note 1411 Waveforms (Continued) GATE GATE Vds Vds FIGURE 11A. AROUND INPUT PEAK FIGURE 11B. AROUND INPUT VALLEY FIGURE 11. THE GATE SIGNAL AND DRAIN-SOURCE VOLTAGES Performance of ISL6745UEVAL2Z The schematic of the ISL6745UEVAL2Z evaluation board is shown in page 12. The bill of material (BOM) for universal AC application is shown on page 8. Figure 1 on page 1 shows photographs of the drive board and LED board. The configuration of the test bench is shown in Figure 12. CURRENT PROBE 110VAC PAC UTILITY ~ DMM ~ P2 0V ~ 275VAC ISOLATED P4 - P9 P1 LED DRIVER LED BOARD P8 P3 + 50V ~ 58VDC PM FIGURE 12. TEST BENCH CONFIGURATION TABLE 2. TEST BENCH CONFIGURATION TEST PM DMM PAC Power Meter Digital Multimeter Programmable AC Power Supply To perform the bench testing, the following equipment is necessary: • Programmable AC power supply, 275VAC minimum • Fan to cool heatsinks • Oscilloscope, 4 channels, 20MHz minimum bandwidth • DC electronic load, 1A minimum • DC Multimeter • Power meter with power factor calculation 6 When operating the evaluation board, certain precautions need to be followed. 1. The power stage of the evaluation board has exposed high voltage and demands extra caution when operating. The voltage rating of the probes should meet the highest voltage present in the board. Isolation of the oscilloscope power source is needed when doing the measurement. 2. Power source considerations: It is important to choose the correct connector when attaching the source supply. An appropriate AC power supply is needed with adjustable output voltage (up to 300V) and current (up to 0.5A) with current limit capability. 3. Loading considerations: It is important to have a firm connection when attaching the load. In case an electronic load is used instead of the LED board, an appropriate electronic load with current up to 500mA and voltage up to 80V is desirable. 4. Air flow conditions: Full rated power should never be attempted without providing the specified 200 CFM of airflow over the LED board. This can be provided by a stand-alone fan. 5. When applying power the first time, it is suggested to apply light load, and set the current limit of the source supply to less than 1.5x of the wattage of the load. Start the circuit with the minimum AC voltage (80V). A quick efficiency check is the best way to confirm proper operation. 6. To measure the output voltage ripple more accurately, it is suggested to measure as closely as possible to the converter’s output terminals. Since the AC signal being measured is small relative to the DC level, care must be exercised to minimize noise pick-up from external sources. The bandwidth of the oscilloscope can be set to 20MHz. Use very short and direct connections to the oscilloscope probe such that the total loop area in the signal and ground connections is as small as possible. AN1411.3 June 9, 2009 Application Note 1411 1. As the FET is on, VDS is zero. The input voltage is applied to the inductor L1, and the same voltage is applied to L2. During this interval, the output load is powered by the output capacitor. 2. When the FET gate signal is removed, the current in inductor L1 begins to charge the capacitor C2 and the output capacitor CO through the output diode. At the same time, the inductor L2 also charges the output capacitor. Power transfers from input to output. 3. Oscillation begins as this period is ended indicating DCM operation. 67 OUTPUT VOLTAGE (V) 66 65 64 63 62 61 60 59 58 0 50 100 150 200 250 300 350 LED CURRENT (mA) FIGURE 13. OUTPUT VOLTAGE vs CURRENT 3.0 RIPPLE VOLTAGE (V) 2.5 2.0 1.5 1.0 0.5 0 0 50 100 150 200 250 LED CURRENT (mA) 300 FIGURE 14. OUTPUT VOLTAGE RIPPLE (P-P) 350 1.00 400mA 0.99 0.98 POWER FACTOR Figure 10 is the drain-source voltage of the switch. In Figure 11, the D-S voltages of the MOSFET are shown with the corresponding gate signal at input peak and valley, respectively. Three distinct modes of operation can be observed. 0.97 300mA 0.96 200mA 0.95 0.94 0.93 0.92 100mA 0.91 0.90 80 160 INPUT VOLTAGE (V) 240 FIGURE 15. INPUT POWER FACTORS Figures 4, 5 and 6 show the input current and the voltage across the input capacitor C1 for low line and high line operations. As can be seen from these waveforms, the power factor is comparatively high. Several possibilities can deteriorate the performance of the regulator: 1. L1 and L2 do not meet the design constraints causing the converter to operate in continuous conduction mode (CCM). Therefore, the energy stored in the inductors will be released to the DC capacitor C1, which will cause input current waveform distortion. 2. The control bandwidth exceeds. 3. The current sense signal reaches the peak current protection threshold. This may be caused by the saturation of the inductor, or improper setting of the current sense resistor, or OCP limit. 4. Improper choice of the output capacitor. 5. The intermediate capacitor C2 is too big so that the voltage across it does not track the input voltage. The input current can be more distorted for high line operation since the capacitor C2 can only be optimized for one input voltage. 6. The inductors get saturated. In this case, the peak current limit will be exceeded and the current waveform will contain large amount of third order harmonics. The output voltage and LED current are shown in Figures 7, 8 and 9 for various load conditions. The voltage across the LED strings (of 21 LEDs in series) is shown in Figure 13. The output voltage increases almost linearly with the LED current as expected. The ripple of the output voltage is governed by Equation 16 and is in proportion to the output power. The relation of the ripple to the load current is shown in Figure 14. The power factor versus input voltage for different LED currents is shown in Figure 15. For most of the operational conditions, the power factor is above 0.9. CAUTION: This evaluation unit should be used and operated only by persons experienced and knowledgeable in the design and operation of high voltage power conversion equipment. Use of this evaluation unit constitutes acceptance of all risk inherent in the operation of equipment having accessible hazardous voltage. Careless operation may result in serious injury or death. Use safety classes of other suitable eye protection. The maximum voltage of ISL6745LEVAL2Z is 140V. 7 AN1411.3 June 9, 2009 Application Note 1411 Bill of Materials for ISL6745UEVAL2Z MANUFACTURER PART NUMBER QTY REF DES VALUE VOLTAGE TOL PACKAGE Panasonic ECQU2A224ML 2 C1, C14 0.1µF 250VAC T-H Murata GRM31BR72J472KW01L 3 C2 4.7nF 630VAC 1206 Placeholder Murata GRM43QR72J683KW01L C17, C18 1 C3 68nF 630V 1812 1 C4 330µF 100V T-H 1 C5 220pF 630V 1206 Murata 1 C6 2.2µF 25V 10% 0603 Murata 1 C7 2.2µF 25V 10% 0805 Nippon Chem TDK C3216COG2J221J Murata GRM188R71H221KA01D 2 C8, C13 220pF 50V 10% 0603 Murata GRM32ER61C476ME15L 1 C10 47µF 16V 10% 1210 Murata GRM188R71H331KA01D 3 C9, C11, C12 330pF 50V 10% 0603 Murata GRM31CR72A105KA01L 1 C15 1.0µF 100V 10% 1206 Murata GRM188R71H221KA01D 1 C16 220pF 50V 10% 0603 Murata GRM188R71H221KA01D 1 C19 220pF 50V 10% 603 Diodes, Inc 1N4007 1 BR1~BR4 2A 1000V T-H Diodes, Inc BYG24J 2 CR2, CR4 2A 600V SMB OnSemi MMSD4148 1 CR3 0.2A 100V SOD123 LittelFuse 396-1200xxxx 1 F1 2A Connector, DNP 1 J1 CoilCraft MSD1278-824KLB 1 L1 820µH 1.9A SMT CoilCraft MSD1278-823KLB 1 L2 82µH 1.0A SMT CoilCraft MSS1278-334KLB 1 L4 330µH 1A SMT Test points T-H P1 to P4, P5 to P7 TP-150C100P Infineon SPD03N60C3 1 Q1 3.2A 650V D-PAK OnSemi MJD50 1 Q2 1A 500V D-PAK Diodes, Inc BSS138 1 Q3 200mA 50V SOT-23 2 R1, R2 1M 1% 1206 2 R3, R4 2.55k 1% 2512 2 R5, R6 49.9k 1% 1206 1 R7 30.1k 1% 0603 1 R8 10k 1% 0603 1 R9 100k 1% 0603 1 R10 1.43k 1% 0603 1 R11 10k 1% 0603 1 R12 34.0k 1% 0603 1 R13 10.0 1% 1206 1 R14 100mΩ 1% 2512 2 R15, R16 100 1% 2512 1 R17 7.15 1% 2512 8 AN1411.3 June 9, 2009 Application Note 1411 Bill of Materials for ISL6745UEVAL2Z (Continued) MANUFACTURER PART NUMBER DNP QTY REF DES VALUE 1 R18 10.0k 1 R19 POT31 1 R20 1k 1 R21 10/1W 1 R22 909k Test point, DNP VOLTAGE TOL 1% PACKAGE 0603 T-H 1% 603 2512 1% TP1 to TP4 603 pad-70c43p Intersil ISL6745AUZ 1 U1 MSOP-10 Intersil EL5220 1 U2 SO-8 Diodes, Inc AP432-SR 1 U3 SOT-23R Philips BZX84-C11 1 VR1 11V LittelFuse TMOV14R260E 1 Z1 250VAC 5% SOT-23 T-H Bill of Materials for ISL6745LEVAL2Z PART NUMBER MANUFACTURER REFERENCE DESIGNATOR QTY DESCRIPTION TBD ISL6745EVAL2ZREVAPCB 1 SEE LABEL-RENAME BOARD PWB-PCB, ISL6745EVAL2Z, REVA, ROHS TDK C3216C0G2J221J-T 1 C5 CAP, SMD, 1206, 220pF, 630V, 5%, COG, ROHS PANASONIC ECQ-U2A224ML 2 C1, C14 (C1-Install on back of board) CAP, RADIAL, 17.5x16, 0.22µF, 250/275V, 20%, POLY FILM, ROHS MURATA GRM31BR72J472KW01L 1 C2 CAP, SMD,1206, 4700pF, 630V, 10%, X7R, ROHS MURATA GRM43QR72J683KW01L 1 C3 CAP, SMD,1812, 0.068µF, 630V, 10%, X7R, ROHS MURATA H1045-00221-50V10-T 3 C8, C13, C16 CAP, SMD, 0603, 220pF, 50V, 10%, X7R, ROHS MURATA H1045-00225-16V10-T 1 C6 CAP, SMD, 0603, 2.2µF, 16V, 10%, X5R, ROHS YAGEO H1045-00331-50V10-T 3 C9, C11, C12 CAP, SMD, 0603, 330pF, 50V, 10%, X7R, ROHS H1045-DNP 0 C19 CAP, SMD, 0603, DNP-PLACE HOLDER, ROHS PANASONIC H1046-00225-25V10-T 1 C7 CAP, SMD, 0805, 2.2µF, 25V, 10%, X5R, ROHS VENKEL H1065-00105-100V10-T 1 C15 CAP, SMD,1206, 1µF, 100V, 10%, X7R, ROHS TDK H1082-00476-16V20-T 1 C10 (Use on 1206 pad layout) CAP, SMD, 1210, 47µF, 16V, 20%, X5R, ROHS NICHICON UVZ2A102MHD 1 C4 CAP, RADIAL, 5x11, 1000µF, 100V, 20%, ALUM.ELEC., ROHS COILCRAFT MSD1278-393MLB 1 L2 COIL-COUPLED INDUCT, SMD, 12.3mm, 39µH, 20%, 5.5A, ROHS COILCRAFT MSD1278-394KLB 1 L1 COIL-COUPLED INDUCT, SMD, 12.3mm, 390µH, 10%, 1.7A, ROHS COILCRAFT MSS1278-334KLB 1 L4 COIL-PWR INDUCTOR, SMD, 12.3mm, 330µH, 10%, 2A, ROHS KEYSTONE 1514-2 4 P1, P2, P8, P9 CONN-TURRET, TERMINAL POST, TH, ROHS DIODES INC. 1N4007 4 BR1-BR4 DIODE-RECTIFIER, AXIAL, DO-41, 1000V, 1A, ROHS VISHAY BYG24J/TR3 2 CR2,CR4 DIODE-RECTIFIER, SMD, 2P, SMA, 600V, 1.5A, ROHS 9 AN1411.3 June 9, 2009 Application Note 1411 Bill of Materials for ISL6745LEVAL2Z (Continued) PART NUMBER MANUFACTURER REFERENCE DESIGNATOR QTY DESCRIPTION NXP SEMICONDUCTORS BZX84-C11-T 1 VR1 DIODE-ZENER, SMD, SOT23,10.4V to 11.6V, 5%, 200mA, ROHS FAIRCHILD MMSD4148-T 1 CR3 DIODE-SWITCHING, SMD, 2P, SOD-123, 100V, 200mA, ROHS INTERSIL ISL6745AUZ 1 U1 IC-HIGH SPEED BRIDGE CONTROLLER, 10P, MSOP, ROHS FAIRCHILD LM358AM 1 U2 IC-DUAL OP AMP, 8P, SOIC, ROHS TEXAS INSTRUMENTS LM4041DIDBZR-T 1 U3 IC-ADJ.SHUNT VOLT.REF, SMD, 3P, SOT-23, 1.225V to 10V, 12mA, ROHS ON SEMICONDUCTOR BSS138LT1G-T 1 Q3 TRANSIST-MOS,N-CHANNEL, SMD, 3P, SOT23, 50V, 200mA, ROHS ON SEMICONDUCTOR MJD47T4G-T 1 Q2 TRANSISTOR, NPN, SMD, 3P, D-PAK, 50V, 1A, BIPOLAR, ROHS INFINEON TECHNOLOGY SPD03N60C3T 1 Q1 TRANSISTOR-MOS, N-CHANNEL, SMD, D2-PAK, 650V, 3.2A, ROHS KOA H2511-01000-1/10W1-T 1 R16 RES, SMD, 0603, 100Ω, 1/10W, 1%, TF, ROHS KOA H2511-01001-1/10W1-T 1 R20 RES,SMD,0603, 1k, 1/10W, 1%, TF, ROHS KOA H2511-01002-1/10W1-T 3 R8,R11,R18 RES,SMD, 0603, 10k, 1/10W, 1%, TF,ROHS H2511-01003-1/10W1-T 1 R9 RES,SMD, 0603, 100k, 1/10W, 1%, TF, ROHS PANASONIC H2511-01431-1/10W1-T 1 R10 RES, SMD, 0603, 1.43k, 1/10W, 1%, TF, ROHS VENKEL H2511-03012-1/10W1-T 1 R7 RESISTOR, SMD, 0603, 30.1k, 1/10W, 1%, TF, ROHS VENKEL H2511-03402-1/10W1-T 1 R12 RES, SMD, 0603, 34k, 1/10W, 1%, TF, ROHS VENKEL H2511-09093-1/10W1-T 1 R22 RES, SMD, 0603, 909k, 1/10W, 1%, TF, ROHS VENKEL H2513-00100-1/4W1-T 1 R13 RES, SMD,1206, 10Ω, 1/4W, 1%, TF, ROHS VENKEL H2513-01004-1/4W1-T 2 R1,R2 RES, SMD,1206, 1M, 1/4W, 1%, TF, ROHS VENKEL H2513-04992-1/4W1-T 2 R5,R6 RES, SMD, 1206, 49.9k, 1/4W, 1%, TF, ROHS VISHAY H2515-00100-1W1-T 1 R21 RES, SMD, 2512, 10Ω, 1W, 1%, TF, ROHS DALE H2515-00R10-1W1-T 1 R14 RES, SMD, 2512, 0.1Ω, 1W, 1%, TF, ROHS VENKEL H2515-01000-1W1-T 1 R15 RES, SMD, 2512, 100Ω, 1W, 1%, TF, ROHS VENKEL H2515-02551-1W1-T 2 R3,R4 RES, SMD, 2512, 2.55k, 1W, 1%, TF, ROHS VENKEL H2515-07R15-1W1-T 1 R17 RES, SMD, 2512, 7.15Ω, 1W, 1%, TF, ROHS BUSSWIRE-18AWG 1 F1 (Solder wire to pads to create short) WIRE, 18AWG, SOLID, BUS COPPER JUMPER 3M SJ-5003-BLACK 4 Bottom four corners. BUMPONS, 0.44inW x 0.20inH, DOMETOP, BLACK INTERSIL COMMON STOCK 8x12-STATIC-BAG 1 Place assy in bag. BAG, STATIC, 8x12, ZIP LOC DNP 0 C17,C18 DO NOT POPULATE OR PURCHASE DNP 0 J1 DO NOT POPULATE OR PURCHASE DNP 0 P5,P6,P7 DO NOT POPULATE OR PURCHASE DNP 0 R19 DO NOT POPULATE OR PURCHASE DNP 0 TP1-TP4 DO NOT POPULATE OR PURCHASE 10 AN1411.3 June 9, 2009 Application Note 1411 Bill of Materials for ISL6745LEVAL2Z (Continued) MANUFACTURER LITTLEFUSE INC PART NUMBER QTY LABEL-RENAME BOARD 1 LABEL-SERIAL NUMBER 1 TMOV14RP140E 1 11 REFERENCE DESIGNATOR RENAME PCB TO: ISL6745LEVAL2Z. DESCRIPTION LABEL, TO RENAME BRD LABEL, FOR SERIAL NUMBER AND BOM REV # Z1 (Install on back of board) VARISTOR-MOV,RADIAL,DISK,140V,6000A,ROHS AN1411.3 June 9, 2009 ISL6245UEVAL2Z Schematic 5 R21 F1 FUSE TR5 0.5A J1 2 1 R2 1M CON2 C1 Z1 1 1 1 D1 BR2 D17 D9 D16 BR4 D18 2 D2 D7 D10 D15 12 D19 L1 R5 49.9k C3 1 P8 CR2 D3 D6 TP3 D11 D14 D12 D13 D20 2 1 R6 49.9k C17 C18 R15 100 Q1 L2 1 3 CR4 VR1 BZx84-C11 U1 SS RETURN R17 1 ISL6745 VDD RTD VDDP 3 VERR OUTB 4 CS OUTA CT GND TP4 10 C16 220pF R9 100k 9 1 R12 34.0k 7 6 C13 220pF C9 330pF/ COG C12 R10 330pF 2 3 4 OUT1 VDD NIN1 OUT2 PIN1 NIN2 GND PIN2 EL5220 1 P5 EXTVDD CR3 MMSD4148 R22 U2 8 P4 RETURN 2 2 5 D21 0.1nF TP2 1 R7 C8 30.1k 220pF 2 D5 C11 R16 100 R14 1 C10 100µF C5 D4 C4 7 900k C6 6 1µF 8 P9 R19 R20 1k R18 10k DNP P6 C19 R11 IADJ 220pF 10k 5 U3 R8 10k RETURN NOTES: Unless otherwise specified 1) All Capacitors are Ceramic 10% 2) All Resistors are 1% P7 Application Note 1411 Q2 C15 R13 10 1 2 R4 Q3 C7 1.0µF BSS138 D8 TP1 R3 P3 BR3 2 2 C2 1 DUMMY 2 2 P2 N 2 1 BR1 L4 R1 1M C14 3 1 P1 1 L AN1411.3 June 9, 2009 Application Note 1411 ISL6745EVAL2Z Layout FIGURE 16. TOP SILKSCREEN FIGURE 17. BOTTOM SILKSCREEN 13 AN1411.3 June 9, 2009 Application Note 1411 References 1. http://www.iaeel.org/iaeel/news/1993/ett1993/polup_1_93. html 2. Robert U. Ayresa, Leslie W. Ayresa and Vladimir Pokrovskyd, On the efficiency of US electricity usage since 1900, Energy, Volume 30, Issue 7, June 2005, pp 1092-1145. 3. http://www.energystar.gov/index.cfm?c=cfls.pr_cfls 4. Zheludev, N. (2007). The life and times of the LED, a 100year history. Nature Photonics 1 (4): pp 189–192. 5. www.cree.com 6. F. Greenfeld, White LED driver circuits for off-Line applications using standard PWM controllers, Intersil Application Note. 7. Z. Ye, F. Greenfeld, G. Liang, Design considerations of a high power factor SEPIC converter for high brightness white LED lighting applications,” IEEE PESC conference record, 2008, June 2008, Greece, pp 2657-2663. 8. Dixon, High power factor pre-regulator using the SEPIC converter, Unitrode Seminar SEM900, Topic 6, 1993. 9. Min Chen, Anu Mathew, and Jian Sun, Nonlinear Current Control of Single-Phase PFC Converters, IEEE Trans on Power Electronics, Vol. 22, No. 6, NOV. 2007 pp 21872194 10. [G. Spiazzi and P. Mattavelli, Design criteria for power factor pre-regulators based on SEPIC and Cuk converters in continuous conduction mode, Proceedings of IEEE-IAS Annual Meeting, 1994, pp. 1084–1089. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that the Application Note or Technical Brief is current before proceeding. For information regarding Intersil Corporation and its products, see www.intersil.com 14 AN1411.3 June 9, 2009