FAN7318A Fairchild Semiconductor, FAN7318A Datasheet
FAN7318A
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FAN7318A Summary of contents
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... Protected under U.S. patent no. 5,652,479. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Description The FAN7318A is a LCD backlight inverter drive IC that controls P-N half-bridge topology. The FAN7318A provides a low-cost solution and reduces external components by integrating proprietary wave rectifiers for open-lamp protection and regulation. The operating voltage range is wide external regulator isn’ ...
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... Analog Dimming - 52μA burst sink current on OLP max. OLP1 Min. & Max. Detector /Full or Half Wave Rectifier OLP2 OLP min. 0.7V/0.5V Striking/normal © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Short-Lamp Protection - + Over-Voltage Protection Protection + - + 2V - 0μA + 3μA - Error. Amp. source current change - Gm Amp ...
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... Pin Configuration 16 1 © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0 PXYTT FAN7318A Figure 2. Package Diagram www.fairchildsemi.com ...
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... TIMER pin capacitor and another internal current source; 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. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Description 4 www.fairchildsemi.com ...
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... 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 # © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Parameter (1,2) Name Value TIMER 7 CMP 7 ADIM REF 7 BCT 7 BDIM 7 ENA 7 GND ...
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... Burst Oscillation Frequency oscb I BCT Discharge current bctdc V BCT High Voltage bcth V BCT Low Voltage bctl © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 =15V, and -25°C ≤ T ≤ 85°C, unless otherwise specified. Specifications to -25° Test Conditions Increase V IN Decrease V V =4.5V IN ...
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... V OLR Input Voltage Range olrr Note: 3. These parameters, although guaranteed, are not 100% tested in production. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) =15V, and -25°C ≤ T ≤ 85°C, unless otherwise specified. Specifications to -25° Test Conditions ADIM=0V, T ADIM=0V ADIM=0 ...
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... Minimum Duty Cycle MIN DC Maximum Duty Cycle MAX Note: 4. These parameters, although guaranteed, are not 100% tested in production. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) =15V, and -25°C ≤ T ≤ 85°C, unless otherwise specified. Specifications to -25° Test Conditions (4) Striking ...
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... Typical Performance Characteristics Figure 3. Start Threshold Voltage vs. Temperature Figure 5. Startup Current vs. Temperature Figure 7. Standby Current vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Figure 4. Start Threshold Voltage Hysteresis vs. Temperature Figure 6. Operating Current vs. Temperature Figure 8. 5V Regulation Voltage vs. Temperature 9 www.fairchildsemi.com ...
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... Typical Performance Characteristics Figure 9. Oscillation Frequency vs. Temperature Figure 11. CT High Voltage vs. Temperature Figure 13. Burst Dimming Frequency vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) Figure 10. Oscillation Frequency in Striking vs. Temperature Figure 12. CT Low Voltage vs. Temperature Figure 14. BCT Discharge Current vs. Temperature 10 www.fairchildsemi.com ...
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... Figure 15. BCT High Voltage vs. Temperature Figure 17. Analog Dimming Reference Voltage 00 vs. Temperature Figure 19. Error Amplifier Source Current 1 vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) Figure 16. BCT Low Voltage vs. Temperature Figure 18. Analog Dimming Reference Voltage 05 vs. Temperature Figure 20. Error Amplifier Source Current 2 vs ...
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... Figure 21. Error Amplifier Source Current for OLR vs. Temperature Figure 23. Burst CMP Sink Current vs. Temperature Figure 25. Open-Lamp Protection Voltage 1 vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) Figure 22. Error Amplifier Sink Current vs. Temperature Figure 24. OLR Error Amplifier Sink Current vs. Temperature Figure 26 ...
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... Figure 27. Short-Lamp Protection Voltage vs. Temperature Figure 29. Open-Lamp Regulation Voltage 2 vs. Temperature Figure 31. TIMER Threshold Voltage 1 vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) Figure 28. Open-Lamp Regulation Voltage 1 vs. Temperature Figure 30. Open-Lamp Regulation Voltage 3 vs. Temperature Figure 32. TIMER Threshold Voltage 2 vs ...
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... Typical Performance Characteristics Figure 33. TIMER Current 1 vs. Temperature © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 (Continued) Figure 34. TIMER Current 2 vs. Temperature 14 www.fairchildsemi.com ...
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... If the product of RT and CT value is constant, the striking frequency is depending on CT and is calculated as: © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0 str value. The UVLO IN ...
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... Lamp Current Figure 38. Analog Dimming Waveforms Burst Dimming Lamp intensity is controlled with the BDIM signal over a wide range. FAN7318A provide polarity selection. When BDIM is inputted, the DC voltage or PWM pulse signal and BCT is setting sawtooth waveform or DC voltage, respectively. This structure can be implemented as negative dimming polarity. When BDIM voltage is lower than BCT voltage, the lamp current is turned on ...
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... Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Soft-Start A soft-start circuit ensures a gradual increase in the input and output power. FAN7318A has no soft-start pin, but provides soft-start function using the first BCT waveform. The first BCT waveform limits CMP voltage at initial operation, so lamp current increases gradually. ...
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... Lamp Current Feedback Circuit FAN7318A has two OLP pins for lamp current feedback and protections. The inputs of two OLP pins are connected to the internal half-wave and full-wave rectifier circuits. The half-wave rectified signals of two OLP inputs are connected the maximum detector circuit. ...
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... Figure 53. Figure 53. Open-Lamp Protection in Striking Mode © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 The IC starts operating in striking mode and remains in striking mode until 17 pulses of and OLR<1.34V occur. If more than 17 pulses and OLR<1.34V, the IC changes from striking mode into normal mode, as shown in Figure 54 ...
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... Applying voltage lower than 2.1V to the ENA pin enables OLP. Applying voltage higher than 2.5V to the ENA pin disables OLP and is called as DCR mode. Regardless of DCR mode, OLP is enabled in striking mode. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0 Lam Figure 58. Open-Lamp Protection Disable in ...
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... If so, CMP-high protection can be disabled, as shown Figure 63. This protection is disabled in striking mode to ignite the lamps reliably. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Figure 63. CMP-High Protection Disable by a Pull- Down Resistor Thermal Shutdown The IC provides the function to detect the abnormal over-temperature. If the IC temperature exceeds approximately 150° ...
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... Application 22-Inch LCD Monitor 1. Features High-Efficiency, Single-Stage Power Conversion P-N Half-Bridge Topology Reduces Required External Components Enhanced System Reliability through Protection Functions © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 Device Input Voltage Range FAN7318A 15V ± 10% Figure 64. Typical Application Circuit 22 Number of Lamps 2 www ...
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... 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/. © 2009 Fairchild Semiconductor Corporation FAN7318A • 1.0.0 10.00 A 9.80 8.89 ...
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... Fairchild Semiconductor Corporation FAN7318A • 1.0.0 24 www.fairchildsemi.com ...