FAN7317MX

FAN7317 LCD Backlight Inverter Drive IC Features Description

















The FAN7317 is a LCD backlight inverter drive IC that controls P-N full-bridge topology by using the new proprietary phase-shift method. High-Efficiency Single-Stage Power Conversion Wide Input Voltage Range: 6V to 24V Backlight Lamp Ballast and Soft Dimming Minimal Required External Components Precision Voltage Reference Trimmed to 2% ZVS Full-Bridge Topology Soft-Start PWM Control at Fixed Frequency Burst Dimming Function Programmable Striking Frequency Open-Lamp Protection Open-Lamp Regulation Arc Protection Short-Lamp Protection CMP-High Protection High-FB Protection Thermal Shutdown 20-Pin SOIC The FAN7317 provides a low-cost solution and reduces external components by integrating full wave rectifiers for open-lamp protection and regulation. The operating voltage range of the FAN7317 is wide, so an external regulator isn’t necessary to supply the voltage to the IC. The FAN7317 provides various protections, such as open-lamp regulation, open-lamp protection, arc protection, short-lamp protection, CMP-high protection, and FB-high protection, to increase the system reliability. The FAN7317 provides burst dimming function and analog dimming is possible, in a narrow range, by adding some external components. The FAN7317 is available in a 20-SOIC package. Applications

LCD TV LCD Monitor Ordering Information Part Number Package Operating Temperature Packing Method FAN7317M 20-SOIC -25 to +85°C RAIL FAN7317MX 20-SOIC -25 to +85°C TAPE & REEL All packages are lead free per JEDEC: J-STD-020B standard. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com FAN7317 — LCD Backlight Inverter Drive IC June 2011 Short Lamp Protection Min. OLR1 - Disable @ striking 1ms delay (operation @ burst dimming on) + 0.3V OUTA Arc Protection TSD 150oC + - 3V OLR2 Min. & Max. Detector /Full Wave Recifier Over-Voltage Protection Max. OLR3 Disable @ striking OLR output 32 count @ normal Reset by BCT edge detect + 2V + 2V OUTB Protection Output Driver 7V 0.2A/0.3A dead time 200ns 1.6s delay @ striking 10ms delay @ normal - OUTC OLR4 0µA + 1.8V Error. Amp. source current change Open Lamp Regulation 2.2V OUTD 1µA - Gm Amp. + Gm = 350, Max. current 85µA max. 2V Oscillator Control Logic On @ striking CT min. 0.5V GND + CMP Error. Amp. source 0µA sink current @ striking current change Error Amp. + + Linear region 0~4V - 3V 52µA burst sink current on High FB Protection disable @ striking 3.5V ENA High_FB Striking off OLP1 5V, max. 3mA Voltage Reference & Internal Bias REF 4 Output Pulses Counter OLP2 Min. & Max. Detector /Full Wave Rectifier max. 2V OLP 1V/0.5V Striking/normal + 150µs Delay min. 0.5V BCT 52µA burst sink current on + OLP min. - OLP4 1.35V 200k + OLP max. OLP3 VIN + Hys. 0.45V - - High_CMP UVLO 5.5V + 1.35V - High CMP Protection disable @ striking BDIM Figure 1. Internal Block Diagram © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 2 FAN7317 — LCD Backlight Inverter Drive IC Block Diagram FAN7317 — LCD Backlight Inverter Drive IC Pin Configuration F Figure 2. Package Diagram © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 3 Pin # Name 1 REF This pin is 5V reference output. Typically, resistors are connected to this pin from CT pin and BCT pin. 2 BDIM This pin is the input for burst dimming. The voltage range of 0.5 to 2V at this pin controls burst mode duty cycle from 0% to 100%. 3 BCT This pin is for programming the frequency of the burst dimming. Typically, a capacitor is connected to this pin from ground and a resistor is connected to this pin from the REF pin. OLP1 This pin is for open-lamp protection and feedback control of lamp currents. It has the same functions as other OLP pins and is connected to the full-wave rectifier internally. In striking mode, if the minimum of rectified OLP inputs is less than 1V for 1.6s; or in normal mode, if the minimum of rectified OLP inputs is less than 0.5V for 10ms; the IC shuts down to protect the system in open lamp condition. The maximum of rectified OLP inputs is inputted to the negative of the error amplifier for feedback control of lamp current. 5 OLR1 This pin is for open-lamp regulation. It has the same functions as other OLR pins and is connected to the full-wave rectifier internally. When the maximum of rectified OLR inputs is between 1.8V and 2V, the error amplifier output current is limited to 1µA; and when the maximum of rectified OLR inputs reaches 2V, the error amplifier output current is 0A and its output voltage maintains constant. The maximum of rectified OLR inputs is inputted to the negative of another error amplifier for feedback control of lamp voltage. When the maximum of rectified OLR inputs is more than 2.2V, another error amplifier for OLR is operating and lamp voltage is regulated. 6 OLP2 This pin is for open-lamp protection and feedback control of lamp currents. Its functions are the same as the OLP1 pin. 7 OLR2 This pin is for open-lamp regulation. Its functions are the same as the OLR1 pin. 8 GND This pin is the ground. 9 OUTB This pin is NMOS gate-drive output. 10 OUTA This pin is PMOS gate-drive output. 11 OUTC This pin is PMOS gate-drive output. 12 OUTD This pin is NMOS gate-drive output. 13 VIN 14 OLR3 This pin is for open-lamp regulation. Its functions are the same as the OLR1 pin. 15 OLP3 This pin is for open-lamp protection and feedback control of lamp currents. Its functions are the same as the OLP1 pin. 16 OLR4 This pin is for open-lamp regulation. Its functions are the same as the OLR1 pin. 17 OLP4 This pin is for open-lamp protection and feedback control of lamp currents. Its functions are the same as the OLP1 pin. 18 ENA This pin is for turning on/off the IC. 19 CMP Error amplifier output. Typically, a compensation capacitor is connected to this pin from the ground. 20 CT This pin is for programming the switching frequency. Typically, a capacitor is connected to this pin from ground and a resistor is connected to this pin from the REF pin. 4 Description This pin is the supply voltage of the IC. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 4 FAN7317 — LCD Backlight Inverter Drive IC Pin Definitions Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Symbol Parameter VIN IC Supply Voltage TA Operating Temperature Range TJ Operating Junction Temperature TSTG Storage Temperature Range θJA Thermal Resistance Junction-Air PD Power Dissipation Min. Max. Unit 6 24 V -25 +85 °C +150 °C +150 °C 90 °C/W 1.4 W -65 (1,2) Notes: 1. Thermal resistance test board. Size: 76.2mm x 114.3mm x 1.6mm (1S0P); JEDEC standard: JESD51-2, JESD51-3. 2. Assume no ambient airflow. Pin Breakdown Voltage Pin # Name Value 1 REF 2 BDIM Unit Pin # Name Value 7 11 OUTC 24 7 12 OUTD 7 3 BCT 7 13 VIN 24 4 OLP1 ±7 14 OLR3 ±7 5 OLR1 ±7 15 OLP3 ±7 6 OLP2 ±7 16 OLR4 ±7 7 OLR2 ±7 17 OLP4 ±7 8 GND 7 18 ENA 7 9 OUTB 7 19 CMP 7 10 OUTA 24 20 CT 7 © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 V Unit V www.fairchildsemi.com 5 FAN7317 — LCD Backlight Inverter Drive IC Absolute Maximum Ratings For typical values, TA = 25°C, VIN = 15V, and -25°C ≤ TA ≤ 85°C, unless otherwise specified. Specifications to -25°C ~ 85°C are guaranteed by design based on final characterization results. Symbol Parameter Test Conditions Min. Typ. Max. Unit Start Threshold Voltage 4.9 5.2 5.5 V Start Threshold Voltage Hysteresis 0.20 0.45 0.60 V Under-Voltage Lockout Section (UVLO) Vth Vthhys Ist Start-up Current VIN = 4.5V 70 100 µA Iop Operating Supply Current VIN = 15V, Not switching 2.0 3.5 mA 5 V 0.7 V 120 170 µA 130 200 270 kΩ 4.9 5.0 5.1 V 50 mV 50 mV ON/OFF Section Von On State Input Voltage Voff Off Stage Input Voltage Isb Stand-by Current RENA 2 VIN = 15V, ENA = Low Pull-down Resistor Reference Section (Recommend 1µF X7R Capacitor) 5V Regulation Voltage 0 ≤ I5 ≤ 3mA V5line 5V Line Regulation 6 V5load 5V Load Regulation I5 = 3mA V5 (( VIN ((( 24V Oscillator Section (Main) fosc fstr Ictdcs Ictdc Oscillation Frequency Oscillator Frequency in Striking Mode CT Discharge Current TA = 25°C, CT = 220pF, RT = 100kΩ 93.9 97.0 100.5 CT = 220pF, RT = 100kΩ 93 97 101 TA = 25°C, CT = 220pF, RT = 100kΩ 120 124 129 CT = 220pF, RT = 100kΩ 119 124 129 Striking 0.99 1.14 1.29 mA Normal 740 840 940 µA Striking -15 -12 -9 µA kHz kHz Ictcs CT Charge Current Vcth CT High Voltage 2 V Vctl CT Low Voltage 0.4 V Oscillator Section (Burst) foscb Burst Oscillation Frequency TA = 25°C, BCT = 4.7nF, BRT = 1.4MΩ 303 314 326 BCT = 4.7nF, BRT = 1.4MΩ 302 314 326 14 26 38 Hz Ibctdc BCT Discharge Current Vbcth BCT High Voltage 2 V Vbctl BCT Low Voltage 0.5 V © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 µA www.fairchildsemi.com 6 FAN7317 — LCD Backlight Inverter Drive IC Electrical Characteristics For typical values, TA = 25°C, VIN = 15V, and -25°C ≤ TA ≤ 85°C, unless otherwise specified. Specifications to -25°C ~ 85°C are guaranteed by design based on final characterization results. Symbol Parameter Test Conditions Min. Typ. Max. Unit Error Amplifier Section (3) AV Open-loop Gain Gm Error Amplifier Trans-conductance lsin Output Sink Current lsur Output Source Current Ibsin Burst CMP Sink Current V135p OLP Input Current Iolpo OLP Output Current OLP Input Voltage Range dB 20 40 60 µmho OLP = 2.25V -50 -35 -20 µA OLP = 0.8V 12 22 32 µA 38 52 66 µA 1.275 1.350 1.421 1.255 1.350 1.444 OLP = 2V -1 0 1 µA OLP = -2V -30 -20 -10 µA 4 V -0.1 µA TA = 25°C 1.35V Regulation Voltage Iolpi Volpr 37 (3) -4 V Open-Lamp Regulation Section Iolr1 Iolr2 Error Amplifier Source Current for Open-Lamp Regulation Striking, OLR = Volr1+0.05 -2.0 OLR = 2.1V -1.0 0 µA Volr1 Open-Lamp Regulation Voltage 1 Striking 1.65 1.80 1.95 Volr2 Open-Lamp Regulation Voltage 2 Striking 1.95 2.05 2.15 V Volr3 Open-Lamp Regulation Voltage 3 2.1 2.2 2.3 V OLR Error Amplifier Transconductance 200 350 500 µmho GmOLR V Iolrsi OLR Error Amplifier Sink Current Normal, OLR = 2.5V 50 70 90 µA Iolri OLR Input Current OLR = 1.5V 10 17 24 µA OLR = -1.5V -25 -15 -7 µA 4 V Iolro OLR Output Current Volrr OLR Input Voltage Range (3) -4 Note: 3. These parameters, although guaranteed, are not 100% tested in production. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 7 FAN7317 — LCD Backlight Inverter Drive IC Electrical Characteristics (Continued) For typical values, TA = 25°C, VIN = 15V, and -25°C ≤ TA ≤ 85°C, unless otherwise specified. Specifications to -25°C ~ 85°C are guaranteed by design based on final characterization results. Protection Section Volp0 Open-Lamp Protection Voltage 0 Volp1 Open-Lamp Protection Voltage 1 Vcmpr (4) Open Lamp in Striking 0.95 1.00 1.05 V Open Lamp 0.44 0.51 0.58 V CMP-High Protection Voltage 2.95 3.05 3.15 V Varcp Arc Protection Voltage 2.90 3.05 3.20 V Vhfbp High-FB Protection Voltage 3.4 3.5 3.6 V Vslp Short Lamp Protection Voltage 0.24 0.32 0.40 V Tolps Tolpn Tcmprs Tcmprn (4) (4) Open-Lamp Protection Delay (4) High-CMP Protection Delay (4) Tolr Open-Lamp Regulation Delay Tslp Short Lamp Protection Delay TSD Thermal Shutdown (4) Striking, foscb = 330Hz 1.6 s Normal, fosc = 100kHz 10 ms Striking, foscb = 330Hz 1.6 s Normal, fosc = 100kHz 10 ms Normal, fosc = 100kHz 320 µs Normal, fosc = 100kHz 1 ms 150 °C VIN V (4) Output Section (4) Vpdhv PMOS Gate High Voltage Vphlv PMOS Gate Low Voltage Vndhv NMOS Gate High Voltage Vndlv Vpuv Vnuv Ipdsur Ipdsin Indsur Indsin tr tf NMOS Gate Low Voltage VIN = 15V (4) PMOS Gate Drive Source Current VIN-7 VIN-7.5 V VIN = 15V 6.5 7.0 7.5 V VIN = 4.5V (4) NMOS Gate Drive Sink Current 0 (4) (4) V VIN-0.3 V VIN = 4.5V (4) NMOS Gate Drive Source Current Rising Time VIN-6.5 VIN = 15V PMOS Gate Voltage with UVLO Activated NMOS Gate Voltage with UVLO Activated PMOS Gate Drive Sink Current VIN = 15V 0.3 V VIN = 15V -200 mA VIN = 15V 300 mA VIN = 15V 200 mA VIN = 15V -300 mA (4) VIN = 15V, Cload = 2nF 70 ns (4) VIN = 15V, Cload = 2nF 70 ns fosc = 100kHz 0 % Falling Time Maximum / Minimum Overlap Minimum Overlap Between Diagonal (4) Switches Maximum Overlap Between Diagonal (4) Switches fosc = 100kHz 86 90 % Dead Time PDR_A/NDR_B (4) 150 200 250 ns (4) 150 200 250 ns PDR_C/NDR_D Note: 4. These Parameters, although guaranteed, are not 100% tested in production. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 8 FAN7317 — LCD Backlight Inverter Drive IC Electrical Characteristics (Continued) Figure 3. Start Threshold Voltage vs. Temp. Figure 4. Start Threshold Voltage Hys. vs. Temp. Figure 5. Start-up Current vs. Temp. Figure 6. Operating Current vs. Temp. Figure 7. Standby Current vs. Temp. Figure 8. Pull-down Resistor vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 9 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics Figure 9. 5V Regulation Voltage vs. Temp. Figure 10. Oscillation Frequency vs. Temp. Figure 11. Oscillation Frequency in Striking vs. Temp. Figure 12. CT Discharge Current in Striking vs. Temp. Figure 13. CT Discharge Current vs. Temp. Figure 14. CT Charge Current vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 10 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics (Continued) Figure 15. CT High Voltage vs. Temp. Figure 16. CT Low Voltage vs. Temp. Figure 17. Burst Dimming Frequency vs. Temp. Figure 18. BCT Discharge Current vs. Temp. Figure 19. BCT High Voltage vs. Temp. Figure 20. BCT Low Voltage vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 11 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics (Continued) Figure 21. Error Amp. GM vs. Temp. Figure 22. Error Amp. Sink Current vs. Temp. Figure 23. Error Amp. Source Current vs. Temp. Figure 24. Burst CMP Sink Current vs. Temp. Figure 25. 1.35V Regulation Voltage vs. Temp. Figure 26. OLP Input Current vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 12 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics (Continued) Figure 27. OLP Output Current vs. Temp. Figure 28. Error Amp. Source Current 1 vs. Temp. Figure 29. Error Amp. Source Current 2 vs. Temp. Figure 30. OLR Error Amp. GM vs. Temp. Figure 31. OLR Error Amp. Sink Current vs. Temp. Figure 32. OLR Input Current vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 13 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics (Continued) Figure 33. OLR Output Current vs. Temp. Figure 34. Open-Lamp Protection Voltage1 vs. Temp. Figure 35. High-CMP Protection Voltage vs. Temp. Figure 36. Arc Protection Voltage vs. Temp. Figure 37. Short Lamp Protection Voltage vs. Temp. Figure 38. PMOS Gate Low Voltage vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 14 FAN7317 — LCD Backlight Inverter Drive IC Typical Performance Characteristics (Continued) Burst Dimming Oscillator: The burst dimming timing capacitor (BCT) is charged by the current flowing from the reference voltage source, which is formed by the burst dimming timing resistor (BRT) and the burst dimming timing capacitor (BCT). The sawtooth waveform charges up to 2V. Once the BCT voltage reaches 2V, the capacitor begins discharging down to 0.5V. Next, the BCT starts charging again and a new burst dimming cycle begins, as shown in Figure 40. The burst dimming frequency is programmed by adjusting the BCT and BRT values. The burst dimming frequency is calculated as: UVLO: The under-voltage lockout (UVLO) circuit guarantees the stable operation of the IC’s control circuit by stopping and starting it as a function of the VIN value. The UVLO circuit turns on the control circuit when VIN exceeds 5.2V. When VIN is lower than 4.75V, the IC start-up current is less than 100µA. ENA: Applying voltage higher than 2V to the ENA pin enables the IC. Applying voltage lower than 0.7V to the ENA pin disables the IC. f OSCB = Main Oscillator: In normal mode, the external timing capacitor (CT) is charged by the current flowing from the reference voltage source, which is formed by the timing resistor (RT) and the timing capacitor (CT). The sawtooth waveform charges up to 2V. Once CT voltage reaches 2V, the CT begins discharging down to 0.4V. Next, the CT starts charging again and a new switching cycle begins, as shown in Figure 39. The main frequency is programmed by adjusting the RT and CT value. The main frequency is calculated as: f OSC = 1 [Hz]  3.864 ⋅ RT − 13800  RT ⋅ CT ⋅ ln   2.52 ⋅ RT − 13800  1 [Hz]  0.039 ⋅ BRT − 4500  BRT ⋅ BCT ⋅ ln   0.026 ⋅ BRT − 4500  (3) To avoid visible flicker, the burst dimming frequency should be greater than 120Hz. (1) Figure 40. Burst Dimming Oscillator Circuit Analog Dimming: For analog dimming, the lamp intensity is controlled with the external dimming signal (VADIM) and resistors. Figure 41 shows how to implement an analog dimming circuit. The polarity of OLP1 should be reversed with respect to OLP2. Figure 39. Main Oscillator Circuit In striking mode, the external timing capacitor (CT) is charged by the current flowing from the reference voltage source and 12µA current source, which increases the frequency. If the product of RT and CT value is constant, the striking frequency is depending on CT and is calculated as: f str = 1  13.8 + (3I1 − 4.6I 2 )RT     − I1 ⋅ I 2 ⋅ RT 2  RT ⋅ CT ⋅ ln  + − 13.8 4.6I 3I RT ( ) 1 2    − I ⋅ I ⋅ RT 2   1 2  [Hz] (2) Q I1 = 12 ×10 -6 A, I 2 = 1.128 × 10 -3 A © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 15 FAN7317 — LCD Backlight Inverter Drive IC Functional Description Figure 41. Analog Implementation Circuit In full brightness, the maximum rms value of the lamp current is calculated as: i max rms = 1.35 π 2 2 R S1 [A] (4) The lamp intensity is inversely proportional to VADIM. As VADIM increases, the lamp intensity decreases and the rms value of the lamp current is calculated as: R1 VADIM [A ] 2 2 R S2 R 2 R + R2 R S1 [Ω] = 1 R2 i rms = i max rms − Q R S2 Figure 43. Burst Dimming Waveforms π Burst dimming can be implemented not only DC voltage, but also using PWM pulse as the BDIM signal. Figure 44 shows how to implement burst dimming using PWM pulse as BDIM signal. (5) Figure 42 shows the lamp current waveform vs. VADIM in an analog dimming mode. i max Lamp i min Lamp Figure 42. Analog Dimming Waveforms Figure 44. Burst Dimming Using an External Pulse During striking mode, burst dimming operation is disabled to guarantee continuous striking time. Figure 45 shows burst dimming is disabled during striking mode. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 16 FAN7317 — LCD Backlight Inverter Drive IC Burst Dimming: Lamp intensity is controlled with the BDIM signal over a wide range. When BDIM voltage is lower than BCT voltage, the lamp current is turned on; so, 0V on BDIM commands full brightness. The duty cycle of the PWM pulse determines the lamp brightness. The lamp intensity is inversely proportional to BDIM voltage. As BDIM voltage increases, the lamp intensity decreases. Figure 43 shows the lamp current waveform vs. DIM in negative analog dimming mode. max At the same time, while VOLR is more than 2V, the counter starts counting 32 rectified OLR pulses in normal mode, then the IC enters shutdown, as shown in Figure 49. This counter is reset by detecting the positive edge of BCT. This protection is disabled in striking mode to ignite lamps reliably. Figure 45. Burst Dimming During Striking Mode Output Drives: FAN7317 uses the new phase-shift method for full-bridge Cold Cathode Fluorescent Lighting (CCFL) drive. As a result, the temperature difference between the left and the right leg is almost zero, because ZVS occurs in both of the legs by turns. The detail timing is shown in Figure 46. Figure 47. Open-Lamp Regulation in Striking Mode CMP 2V OLR 2.2V OLR 0 2.2V 2V OLR 0 -2V -2.2V iCMP 0 Figure 46. MOSFETs Gate Drive Signal Figure 48. Open-Lamp Regulation in Normal Mode Protections: The FAN7317 provides the following latchmode protections: Open-Lamp Regulation (OLR), Arc Protection, Open-Lamp Protection (OLP), Short-Lamp Protection (SLP), CMP-High Protection, and Thermal Shutdown (TSD). The latch is reset when VIN falls to the UVLO voltage or ENA is pulled down to GND. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 17 FAN7317 — LCD Backlight Inverter Drive IC Open-Lamp Regulation: When the maximum of the max ) is more than 2V, the rectified OLR input voltages ( VOLR IC enters regulation mode and controls CMP voltage. The IC limits the lamp voltage by decreasing CMP max source current. If VOLR is between 1.8V and 2V, CMP source current decreases from 22µA to 1µA. Then, if max VOLR reaches 2V, CMP source current decreases to 0µA, so CMP voltage remains constant and the lamp voltage also remains constant, as shown in Figure 47. max Finally, if VOLR is more than 2.2V, the error amplifier for OLR is operating and CMP sink current increases, so CMP voltage decreases and the lamp voltage maintains the determined value. 0 2V OLR 0 -2V 32 pulses counting Shut down BCT 0 Counter reset OUTA OUTB 0 OUTC Figure 51. Open-Lamp Protection in Striking Mode OUTD 0 Figure 49. Over-Voltage Protection in Normal Mode Arc Protection: If the maximum of the rectified OLR max ) is higher than 3V, the IC enters input voltages ( VOLR shutdown mode without delay, as shown in Figure 50. CMP 0 3V OLR 0 Shut down OUTA Figure 52. Open-Lamp Protection in Normal Mode OUTB 0 Short-Lamp Protection: If the minimum of the rectified min ) is less than 0.3V in normal mode, OLR voltages ( VOLR the IC is shut down after a delay of 1ms, as shown in Figure 53. This protection is disabled in striking mode to ignite lamps reliably. OUTC OUTD 0 Figure 50. Arc Protection Open-Lamp Protection: If the minimum of the rectified min ) is less than 1V during initial OLP voltages ( VOLP operation, the IC operates in striking mode only for 1.6s, min as shown in Figure 51. After ignition, if VOLP is less than 0.5V in normal mode, the IC is shut down after a delay of 10ms, as shown in Figure 52. Figure 53. Short-Lamp Protection © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 18 FAN7317 — LCD Backlight Inverter Drive IC CMP FAN7317 — LCD Backlight Inverter Drive IC CMP-High Protection: If CMP is more than 3V in normal mode, the IC is shut down after a delay of 10ms, as shown in Figure 54. This protection is disabled in striking mode to ignite lamps reliably. Figure 54. CMP-High Protection High-FB Protection: If the minimum of the rectified OLP max voltages( VOLP ) is more than 3.5V, the counter starts counting eight rectified OLP pulses in normal mode, then the IC enters shutdown, as shown in Figure 55. This counter is reset by detecting the positive edge of BCT. This protection is disabled in striking mode to ignite lamps reliably. CMP 0 3.5V OLP 0 -3.5V 8 pulses counting BCT 0 Shut down Counter reset OUTA OUTB 0 OUTC OUTD 0 Figure 55. High-FB Protection Thermal Shutdown: The IC provides the function to detect the abnormal over-temperature. If the IC temperature exceeds approximately 150°C, the thermal shutdown triggers. © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 19 Application Device Input Voltage Range Number of lamps 22-Inch LCD Monitor FAN7317 13±10% 4 1. Features 11 12 OUTA OUTC 13 10 OUTD OUTB 9 14 GND VIN 15 8 OLR3 OLR2 16 7 OLP3 OLP2 17 6 OLR4 OLR1 5 18 OLP4 OLP1 4 19 ENA BCT 3 20 BDIM CT REF 2 BDIM(0~3.3V) IC1 ON/OFF CMP High-Efficiency Single-Stage Power Conversion P-N Full-Bridge Topology Reduces Required External Components Enhanced System Reliability through Protection Functions 1



Figure 56. Typical Application Circuit 2. Transformer Schematic Diagram Figure 57. Transformer Schematic Diagram 3. Core & Bobbin


Core: EFD2126 Material: PL7 Bobbin: EFD2126 © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 20 FAN7317 — LCD Backlight Inverter Drive IC Typical Application Circuit (LCD Backlight Inverter) Pin No. Wire Turns Inductance Leakage Inductance Remarks 52 1 UEW 0.4φ 17 250µH 16µH 1kHz, 1V 79 1 UEW 0.04φ 2256( = 0+0+376•6) 4.2H 290mH 1kHz, 1V 5. BOM of the Application Circuit Part Ref. Value F1 24V 3A Description Fuse 10k Value Description C14 3.3n 50V 1608 K FUSE C15 100n 50V 1608 K C17 1µ 50V 2012 K 1608 J C18 4.7n 50V 1608 K Resistor (SMD) R1 Part Ref. R2 10k 1608 J C19 3.3n 50V 1608 K R3 200 1608 F C21 3.3n 50V 1608 K R5 100k 1608 F R6 10k 1608 J C4 3p 3KV R7 200 1608 F C13 3p 3KV R8 75k 1608 J C16 3p 3KV R9 10k 1608 J C20 3p 3KV R10 8.2k 1608 J Capacitor (DIP) Electrolytic capacitor R12 10k 1608 J C1 220µ 25V R13 200 1608 F C2 220µ 25V R14 1.5M 1608 F R15 10k 1608 J M1 FDD8424H Fairchild Semiconductor 200 1608 F M2 FDD8424H Fairchild Semiconductor R16 MOSFET (SMD) Capacitor (SMD) Wafer (SMD) C3 1µ 50V 2012 K CN1 12505WR-10 C5 1µ 50V 2012 K CN2 35001WR-02A C6 3.3n 50V 1608 K CN3 35001WR-02A C7 10µ 16V 3216 CN4 35001WR-02A C8 10n 50V 1608 K CN5 35001WR-02A C9 10µ 16V 3216 C10 220p 50V 1608 K TX1 EFD2126 C11 10n 50V 1608 K TX2 EFD2126 C12 1µ 50V 2012 K © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 Transformer (DIP) www.fairchildsemi.com 21 FAN7317 — LCD Backlight Inverter Drive IC 4. Winding Specification 13.00 12.60 A 11.43 20 11 B 9.50 10.65 7.60 10.00 7.40 2.25 1 PIN ONE INDICATOR 10 0.51 0.35 0.25 M 0.65 1.27 1.27 C B A LAND PATTERN RECOMMENDATION 2.65 MAX SEE DETAIL A 0.33 0.20 C 0.75 0.25 0.10 C 0.30 0.10 X 45° SEATING PLANE NOTES: UNLESS OTHERWISE SPECIFIED (R0.10) A) THIS PACKAGE CONFORMS TO JEDEC MS-013, VARIATION AC, ISSUE E B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS DO NOT INCLUDE MOLD FLASH OR BURRS. D) CONFORMS TO ASME Y14.5M-1994 GAGE PLANE (R0.10) 0.25 8° 0° 1.27 0.40 SEATING PLANE (1.40) DETAIL A E) LANDPATTERN STANDARD: SOIC127P1030X265-20L F) DRAWING FILENAME: MKT-M20BREV3 SCALE: 2:1 Figure 58. 20-SOIC Package Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/ © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 22 FAN7317 — LCD Backlight Inverter Drive IC Physical Dimensions FAN7317 — LCD Backlight Inverter Drive IC © 2007 Fairchild Semiconductor Corporation FAN7317 • 1.0.3 www.fairchildsemi.com 23