www.fairchildsemi.com KA7543 Advanced Feedback Dimming Ballast Control IC Features Descriptions • • • • • • • • • • • • • The KA7543 is an advanced lamp current feedback dimming control IC. This ballast control IC provides all of the necessary features to implement wide range dimming control, soft start and constant power consumption for intelligent electronic ballast systems. The KA7543 is optimized for advanced electronic ballast systems requiring minimum board area. External component counts can be reduced by adopting the KA7543. Current feedback control method of the inverter status is one of the most attractive merits in KA7543. Internal soft start circuitry eliminates the need for external soft start discrete components. Voltage controlled soft dimming circuit is built into the IC to control the lighting output in a wide range. Protection circuitry, no lamp protection, abnormal protection, one lamp detection, UVLO, restart on lamp adding , have been added. Lamp Current Feedback Soft Start on Feedback Voltage Dimming (0V~2V) on Feedback Switch off Control (Vdm=5V) Soft Dimming Control No Lamp Protection One Lamp Detection for Feedback Abnormal Protection Low Start-up and Operating Supply Current UVLO with 1.8V Hysteresis Totem Pole Output Trimmed 1.5% Internal Bandgap Reference 14-DIP & 14-SOP Applications • Electronic Ballast • Lighting Control System • Half Bridge Drive Control System 14-DIP 1 14-SOP 1 Rev. 1.0.3 ©2002 Fairchild Semiconductor Corporation KA7543 Internal Block Diagram Output stage OUT1 1 Frequency divider 14 OUT2 13 NC Protection reset + NC 0.7V 2 Reset Cs + - 9.5V Vcc ict - 2V 1.8V + 7V Vz Supply + 3 Limiter + UVLO Q 55pF 8ict + R 12 GND 11 Cdm 4V Q sw S sw 2V Vref (bandgap) Internal bias 2V Cc + Oscillator 1V 7V bias 4 Dimming starter 5.7V 4V + 11µA 2V 5.7V 5V regulator + V5 5 + Mirror - is isr 5V 5/2 Switch Current amp 6 Vr + idr id + 8 Vld 2V is-id ir Vdm + 1/2 5kΩ 9 Soft starter 20kΩ - 2V - Mirror - Gm Cs + + Vfb 10 Gm + Dimmer 20kΩ Selecter - 30kΩ Vab + 7 3pF Q R Q 2V Abnormal protection 2 S - + 3V + 5pF 1V No-lamp pretection KA7543 Pin Assignments OUT2 NC GND Cdm Cs Vdm Vld V5 Vfb Vab KA7543 OUT1 NC Vcc Cc Pin Definitions Pin Number Pin Name Pin Function Description 1 OUT1 Drive Output 1 2 NC No Connection 3 Vcc Supply Voltage Input 4 Cc Compensation Input 5 V5 5V Voltage Source 6 Vfb Negative Feedback Input 7 Vab Abnormal Protection Input 8 Vld Lamp Detection Input Dimming Control Input 9 Vdm 10 Cs 11 Cdm Soft Dimming Control Input 12 GND Ground 13 NC No Connection 14 OUT2 Drive Output 2 Soft Start Time Control Input 3 KA7543 Absolute Maximum Ratings Parameter Symbol Value Unit VCC 30 V IOH, IOL ±300 mA Drive Output Clamping Diodes VO > VCC, or VO < -0.3 Iclamp ±10 mA Operating Temperature Range Topr -25 to 125 °C Storage Temperature Range Tstg -65 to 150 °C Supply Voltage Peak Drive Output Current Power Dissipation Pd 1 W Thermal Resistance (Junction-to-Air) θja 123 °C/W Absolute Maximum Ratings (− −25°°C≤ ≤Ta≤ ≤125°°C) Parameter Symbol Value Unit Temperature Stability For Reference Voltage (Vref) ∆Vref(Typ) 20 mV Temperature Stability For Operating Frequency (fs) ∆fs(Typ) 8 kHz Electrical Characteristics Unless otherwise specified, Vcc=12V, Ta=25°C. Parameter Symbol Conditions Min. Typ. Max. Unit 8.7 9.5 10.3 V 1.5 1.8 2.1 V V UNDER VOLTAGE LOCK OUT SECTION Start Threshold Voltage VTH(st) UVLO Hysteresis HY(st) 5V Reference Voltage(Note1) VCC increasing - V5 I5 = 0mA 4.9 5 5.1 Start Up Supply Current IST Vcc=8.5V - 0.2 0.27 mA Operating Supply Current ICC Output not switching - 7 9 mA IDCC fo = 50kHz, CI=1nF - 8 12 mA Output Sink Current Iea(i) Vfb = 2V 12 15 18 µA Output Source Current Iea(o) Vfb = 0V 12 15 18 µA SUPPLY CURRENT SECTION Dynamic Operating Supply Current (Note1) CURRENT AMPLIFIER SECTION (NOTE1) 4 KA7543 Electrical Characteristics (Continue) Unless otherwise specified, Vcc=12V, Ta=25°C. Parameter Symbol Conditions Min. Typ. Max. Unit 1 Lamp Feedback Voltage Vfb1 Vld = 2V 0.425 0.5 0.575 V 2 Lamp Feedback Voltage Vfb2 Vld = 4V 0.85 1 1.15 V Output Voltage High Vea(h) Vfb = 0V 5.5 5.7 5.9 V Output Voltage Low Vea(l) Vfb = 2V - - 0.4 V kHz OSCILLATOR SECTION(NOTE1) Reference Frequency fref VC = 3.0V 37 45 53 Reference Dead Time td VC = 3.0V 1.2 1.4 1.6 µs Soft Start Frequency fss VC = 0V 77 - - kHz Soft Start Time Current Iss VC = 0V 9.2 11 12.8 µA 0 - 2 V VOLTAGE INPUT DIMMING SECTION(NOTE1) Dimming Voltage Range ∆Vdm - Dimming Start Voltage Vdm Vdm = 0V 3.85 4 4.15 V Initial Dimming Output Voltage Vdm Vdm = 0V -0.1 0 0.1 V OUTPUT 1/2 SECTION Rising Time (Note2) tr Vcc =12V,CI =1nF - 200 280 ns Falling Time(Note2) tf Vcc =12V,CI =1nF - 50 90 ns VCC = 5V, IO =100µA - - 0.9 V Output Voltage With UVLO Activated Vomin(o) PROTECTION SECTION Lamp Detection Voltage Vld - 2.5 3 3.5 V Abnormal Detection Voltage Vab - 1.6 2 2.4 V Switch Off Detection Voltage Vso - 4.7 5 5.3 V No Lamp Detect Voltage Vnd - 0.85 1 1.15 V Vpr - - 0.7 - V PROTECTION RESET SECTION Protection Reset Voltage Notes : 1. This parameter should be tested in Vcc = 11V, 14V, 30V. 2. This parameter, although guaranteed, is not tested in production. 5 KA7543 Operating Description lamp feedback lamp change soft moving on dimming 2Lamp Vcs 2V 1V 1Lamp Vfb 0.5V 2V Vdm 1V 0 t[sec] Figure 1. Operation Characteristics The KA7543 is an advanced, lamp current feedback ballast dimming control IC which drives half bridge converter. This control IC provides all the necessary features to implement wide range dimming control, soft-start and constant power consumption for the intelligent electronic ballast system. The number of external components can be minimized by adopting the KA7543. Protection circuitry, no lamp protection, abnormal protection, one lamp detection, UVLO and restart on lamp adding have been included in the KA7543. Fig. 1 shows the operational characteristic of the KA7543 according to time and lamp count variation. When the Vcc voltage reaches the start-up threshold voltage(9.5V), the soft start capacitor begins to be charged. When the Cs pin voltage, Vcs is over 2V, the soft start operation ends. During the soft start operation, the reference voltage which controls the lamp current is proportional to Vcs. Dimming operation starts when Vcs becomes 4V and the change rate of dimming is determined by the capacitor connected to the Cdm pin. The more smooth dimming can be accomplished by the larger capacitor connected to the Cdm pin. UVLO(Under Voltage Lock Out) To output Reset Cs UVLO 9.5V Vcc 3 - 1.8V 7V Vz Supply + sw 2V Vref (bandgap) 2V Internal bias bias 7V Figure 2. UVLO Until the Vcc voltage reaches the start-up threshold voltage(9.5V), UVLO circuit lowers the IC operating current below 270µA. When the Vcc voltage reaches the start-up threshold voltage, it generates IC reference voltage(Vref) and supplies bias current for the whole circuitry. The hysteresis of UVLO circuit is 1.8V. 6 KA7543 Soft Start Cc 4 Dimming starter 4V + 11µA 5.7V 10 + Mirror is isr Cs Gm + 20kΩ 2V Soft starter Figure 3. Soft Start The soft start circuit charges the soft start capacitor, Cs connected to Cs pin. So the Cs pin voltage increases linearly when start-up and the current(is) makes the reference voltage(Vr) which is proportional to is current. The is current is maximum when the Cs pin voltage is 2V. The highest soft start frequency is determined by the Cc pin voltage(Vbe+2Vd). The operating frequency linearly decreases until the Cs pin voltage reaches 2V. During the soft start operation, the reference voltage which controls the lamp current is proportional to Vcs. If the Cs pin voltage is higher than 2V, the operating frequency is controlled by the feedback reference voltage. The UN-UVLO signal discharges capacitor Cs when the Vcc voltage is lower than UV. Oscillator From Cc Limiter + + ict - 2V + To flip flop Q R + 8ict 55pF 4V Q S sw + 1V Oscillator Figure 4. Oscillator The oscillator block consists of two comparators and the ratio of charging time and discharging time is 7:1. The current source, ict charges 55pF capacitor until the capacitor voltage meets the upper limit voltage. After that time, 7*ict current discharges the capacitor until it meet the lower limit voltage, 1V. The upper limit voltage is between 2V and 4V. The operating frequency is highest when the upper limit voltage is 2V and it is lowest when the upper limit voltage is 4V. The lowest operating frequency guarantees the zero voltage switching operation of the ballast system. 7 KA7543 Dimming Control Stage 11 Cdm CURRENT AMPLIFIER 9 Vdm DIMMING CONTROL 5V Switch - is To output + + Mirror - + idr id + - To error amp (+) is-id 20kΩ 2V Dimmer Figure 5. Dimming Control Stage The condition for full dimming is when the Vdm voltage is 2V and the condition for full lighting is when the Vdm voltage is 0V. Dimming operation starts when Vcs becomes 4V and the change rate of dimming is determined by the capacitor connected to the Cdm pin. The more smooth dimming can be accomplished by the larger capacitor connected to the Cdm pin. If the Vdm pin voltage is higher than 5V, then the output drive stage remains in off state. Dimming control and output drive on/ off control can be achieved with only one pin. Output Drive Stage From protection output from uvlo From oscillator Q Frequency divider 1 OUT1 14 OUT2 Output stage Figure 6. Output Drive Stage OUT1 and OUT2 are complementary and there is 1.4us dead time for the ZVS operation. The structure of output stage is the totem-pole output stage. For the high side MOSFET drive, a pulse transformer is necessary. No Lamp Protection If the Vld pin voltage is lower than 1V, it means that there is no lamp connected. On no lamp condition, the output drive stage is in off state. 8 KA7543 Abnormal Protection To output 30kΩ Vab + 7 3pF S Q R Q 2V Protection reset From no lamp Abnormal protection + 0.7V - Vct Figure 7. Abnormal Protection Circuit The abnormal protection is similar to the over current protection, but it is a protection that detects abnormal connection of lamps. The abnormal protection circuit works when the Vab pin voltage is higher than 2V. The abnormal protection is latched using a flip-flop and the protection is reset when the ballast system restarts. Lamp Selector Stage Cc Vfb 6 Gm Vr 5kΩ + 1/2 ir is-id Selecter - 30kΩ - + 3V + 8 Vld 5pF 1V No-lamp pretection Figure 8. Lamp Selector Stage If the Vld pin voltage is between 1V and 3V, it means that there is one lamp connected and if the Vld pin voltage is over 3V, it is two lamps condition. The feedback reference voltage of the two lamps condition is twice that of one lamp condition. 9 KA7543 Application Circuit <85 ~ 265VAC Input, 400VDC, Fluorescent Lamps Ballast(32W*2 / 36W*2)> T1 D5 D3 C5 D4 R3 D1 R4 R7 D2 R5 D8 NTC Q1 R1 5 6 OUT Idet C6 C2 GND 8 7 C9 C4 Vcc C3 CS MULT R8 4 3 1 C1 2 INV EA_OUT FAN7527B L1 TNR F1 R6 C7 R2 R9 C8 AC INPUT R15 C10 R12 T2 C22C23C13 12 7 10 11 14 4 Q2 6 3 5 9 14 R13 C20 L3 Q3 D6 R11 R10 C18 L2 C14 14 8 C19 C15 R14 1 KA7543 C11 C17 D7 C16 R16 C12 R17 R18 R21 C24 ZD1 Vdm(0~2V) 10 C21 R19 KA7543 Components List (32W*2Lamp Application) Part Number Value Note Manufacturer R1 1.8MΩ 1/4W - R2 25kΩ 1/4W - R3, 21 150kΩ 1W - R4, 11 22kΩ 1/4W - R5 10Ω 1/4W R6 0.68Ω 1W - R7 1.0MΩ 1/4W - R8 6kΩ 1/4W - R9 103 Variable resistor - R10 6.8Ω 1W - R12, 13 47Ω 1W - R14 180kΩ 1/4W - R15, 16 330kΩ 1/4W - R17, 18 680kΩ 1/4W - R19 8.2kΩ 1/4W - C1, 2 150nF, 275Vac Box-Cap - C3, 4 2200pF, 3000V Y-Cap - C5 0.33µF, 630V Miller-Cap - C6, 24 47µF, 35V Electorlytic - C7 1µF MLCC - C8, 11 1nF, 25V Ceramic - C9 47µF, 450V Electorlytic - C10 0.22µF, 25V Ceramic - C12, 21 0.1µF, 25V Ceramic - C13 10nF, 25V Ceramic - C14 1nF, 630V Miller-Cap - C15,16 4700pF, 1000V Miller-Cap - C17, 18, 19, 20 6800pF, 630V Miller-Cap - C22, 23 22µF, 35V Electorlytic - Q1, 2, 3 500V, 4.5A IRFS830B Fairchild D1, 2, 3, 4 1000V, 1A 1N4007 - D5 600V, 1A BYV26C - D6, 7 600V, 1A 1N4937 - D8 75V, 150mA 1N4148 - ZD1 15V, 1W 1N4744 - L1 45mH Line Filter - L2, 3 3.1mH(120T) EI2820 - T1 0.9mH(80T:6T) EI2820 - T2 1.2mH(30T:60T) EE1614 - F1 250V, 3A Fuse - TNR 470V 471 - NTC 10Ω 10D09 11 KA7543 Components List(36W*2Lamp Application) (Continued) 12 Part Number Value Note Manufacturer R1 1.8MΩ 1/4W - R2 22kΩ 1/4W - R3, 21 150kΩ 1W - R4, 11 22kΩ 1/4W - R5 10Ω 1/4W R6 0.68Ω 1W - R7 1MΩ 1/4W - R8 6kΩ 1/4W - R9 103 Variable resistor - R10 6.8Ω 1W - R12, 13 47Ω 1W - R14 180kΩ 1/4W - R15, 16 330kΩ 1/4W - R17, 18 680kΩ 1/4W - R19 8.2kΩ 1/4W - C1, 2 150nF, 275Vac Box-Cap - C3, 4 2200pF, 3000V Y-Cap - C5 0.33µF, 630V Miller-Cap - C6, 24 47µF, 35V Electorlytic - C7 1µF MLCC - C8, 11 1nF, 25V Ceramic - C9 47µF, 450V Electorlytic - C10 0.22µF, 25V Ceramic - C12, 21 0.1µF, 25V Ceramic - C13 10nF, 25V Ceramic - C14 1nF, 630V Miller-Cap - C15,16 3300pF, 1000V Miller-Cap - C17, 18, 19, 20 6800pF, 630V Miller-Cap - C22, 23 22µF, 35V Electorlytic - Q1, 2, 3 500V, 4.5A IRFS830B Fairchild D1, 2, 3, 4 1000V, 1A 1N4007 - D5 600V, 1A BYV26C - D6, 7 600V, 1A 1N4937 - D8 75V, 150mA 1N4148 - ZD1 15V, 1W 1N4744 - L1 45mH Line Filter - L2, 3 3.1mH(120T) EI2820 - T1 0.9mH(80T:6T) EI2820 - T2 1.2mH(30T:60T) EE1614 - F1 250V, 3A Fuse - TNR 470V 471 - NTC 10Ω 10D09 - KA7543 Mechanical Dimensions Package Dimensions in millimeters 2.08 ) 0.082 14-DIP 7.62 0.300 3.25 ±0.20 0.128 ±0.008 5.08 MAX 0.200 1.50 ±0.10 0.059 ±0.004 #8 2.54 0.100 #7 19.40 ±0.20 0.764 ±0.008 #14 19.80 MAX 0.780 #1 0.46 ±0.10 0.018 ±0.004 ( 6.40 ±0.20 0.252 ±0.008 0.20 0.008 MIN 3.30 ±0.30 0.130 ±0.012 +0.10 0.25 –0.05 0~15° +0.004 0.010 –0.002 13 KA7543 Mechanical Dimensions (Continued) Package Dimensions in millimeters 14-SOP MIN #8 0.60 ±0.20 0.024 ±0.008 14 MAX0.10 MAX0.004 1.80 MAX 0.071 5.72 0.225 ° 3.95 ±0.20 0.156 ±0.008 0~ 8 +0.10 0.20 -0.05 +0.004 0.008 -0.002 6.00 ±0.30 0.236 ±0.012 1.27 0.050 #7 +0.10 0.406 -0.05 +0.004 0.016 -0.002 #14 8.70 MAX 0.343 #1 8.56 ±0.20 0.337 ±0.008 ( 0.47 ) 0.019 1.55 ±0.10 0.061 ±0.004 0.05 0.002 KA7543 Ordering Information Product Number Package KA7543 14-DIP KA7543D 14-SOP Operating Temperature -25°°C ~ +125°°C 15 KA7543 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 8/2/02 0.0m 001 Stock#DSxxxxxxxx 2002 Fairchild Semiconductor Corporation