FC2338 FS | Alldatasheet
Document overview
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Technical content
Features
Fast start up and power supply with HV JFET Integrated with 600V Power MOSFET Active PFC for High Power Factor and Low THD ±3% LED Output Current Accuracy Excellent Line and Load Regulation Critical Conduction Mode Operation Ultra Low (300uA) Operating Current LED Short Protection LED Open Protection (OVP) Current Sensing Resistor Open Protection Cycle by Cycle Current Limit VCC Under Voltage Protection Auto Fault Recovery Thermal Regulation Function
Applications
LED retrofit lamps, Bulb, Spot Light, GU10/E27 LED PAR30, PAR38 Lamp LED tube, LED String Other LED Lighting SEMI CONDUCTOR TEC HNIC AL DATA FC2338 2019. 10. 02 1/9Revision No : 0
Ordering Information
Part Number Package Operating Temperature Package Method Marking FC2338 SOP-7 -40 ℃ to 105 ℃ Tape 4,000 pcs/Reel BP2338 XXXXXYS FGXXWWJ Pin Configuration and Marking Information COMP VCC FB DRAIN DRAIN GND BP2338 XXXXXYS FGXXWWJ CS Figure 3. Pin configuration
1 COMP
3 VCC Power Supply Pin. Connect a bypass capacitor from this pin to GND. 5,6 DRAIN Internal HV Power MOSFET Drain.
Absolute Maximum Ratings (note1) Symbol Parameters Range Units VDS Internal HV MOSFET Drain to Source voltage -0.3~600 V ICC_MAX VCC pin maximum sink current 20 mA COMP Compensation pin voltage -0.3~6 V FB Feedback Voltage detection Pin -0.3~6 V CS Current sense pin -0.3~6 V PDMAX Power dissipation (note2) 0.45 W θJA Thermal resistance (Junction to Ambient) 145 ℃/W TJ Operating junction temperature -40 to 150 ℃ TSTG Storage temperature range -55 to 150 ℃ Note 1: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. Under “recommended operating conditions” the device operation is assured, but some particular parameter may not be achieved. The electrical characteristics table defines the operation range of the device, the electrical characteristics is assured on DC and AC voltage by test program. For the parameters without minimum and maximum value in the EC table, the typical value defines the operation range, the a ccuracy is not guaranteed by spec. Note 2: The maximum power dissipation decrease if temperature rise, it is decided by TJMAX, θJA and environment temperature (TA). The maximum power dissipation is the lower one between PDMAX = (TJMAX - TA)/ θJA and the number listed in the maximum table. Recommended Operation Conditions Symbol Parameter Range Unit I LED 1 Output LED current @ Vout=72V Input voltage 90Vac < 220 mA Input voltage 176Vac < 250 mA I LED 2 Output LED current @ Vout=36V Input voltage 90Vac < 320 mA Input voltage 176Vac < 360 mA FC2338 2019. 10. 02 4/9Revision No : 0
Electrical Characteristics (Notes 3, 4) (TA =25℃ Unless otherwise specified, VCC =11.2V) Symbol Parameter Conditions Min Typ Max Units Supply Voltage Section VCC_ON VCC Turn On Threshold VCC Rising 9.0 10.7 12.5 V VCC_UVLO VCC Turn Off Threshold VCC Falling 6.0 7.0 8.2 V VCC_HIGH VCC Charge Limit VCC Rising 9.0 10.7 12.5 V VCC_CLAMP VCC Clamp Voltage 11 14 17 V ICC_UVLO VCC Startup Current VCC Rising, VCC= VCC_ON - 1V 40 80 uA ICC VCC Operating Current FOP=7kHz, 180 300 uA Feedback Section VFB_OVP FB Over Voltage Protection Threshold 1.5 1.65 1.85 V Internal Controller TON_MAX Maximum On Time 4 5.5 8 us TOFF_MIN Minimum Off Time 2 4.2 6 us TOFF_MAX Maximum Off Time 150 us Current Sense Section VCS_LIMIT CS Peak Voltage Limitation 1.5 V TLEB_CS Leading Edge Blanking Time for Current Sense 300 ns TDELAY Switch off Delay Time 200 ns Compensation Section VREF Internal Reference Voltage 0.194 0.200 0.206 V VCOMP_LO COMP Low Clamp Voltage 1.6 V VCOMP_HI COMP High Clamp Voltage 4.0 V FC2338 2019. 10. 02 5/9Revision No : 0
RDS_ON Static Drain-source On- resistance VGS=10V/IDS=0.5A 1.8 Ω BVDSS Drain-Source Breakdown V oltage VGS=0V/IDS=250uA 600 V IDSS Power MOSFET Drain Leakage Current VGS=0V/VDS=600V 1 uA HV JFET IJFET JFET current Drain of JFET to GND 40v 5 9 13 mA BVDSS JFET Drain to Source 600 V IDSS JFET shut down Leakage Current 45 uA Thermal Regulation Section TREG Thermal Regulation Temperature 140 ℃ Note 3: production testing of the chip is performed at 25 C. Note 4: the maximum and minimum parameters specified are guaranteed by test, the typical value are guaranteed by design, characteriza tion and statistical analysis Power MOSFET FC2338 2019. 10. 02 6/9Revision No : 0 Electrical Characteristics (Con.)
&VREF Current Sense PFC Control FB CS DRAIN VCC COMP GND 2 5,6 Driver Thermal Regulation Logic & Protection HV Startup & Power Supply Demag Figure 5. FC2338 Internal Block Diagram
Application Information
The FC2338 integrating a 600V power MOSFET, is a high precision non-isolated buck APFC LED driver, specially designed for universal mains with constant current control. The driver with on-chip PFC circuit achieves high power factor, low THD and high efficiency.
1 Start Up
After system powered on, the capacitor on VCC pin is charged up by the internal JFET. When the VCC pin voltage reaches the turn on threshold, the internal circuits start working. The COMP pin voltage is pulled up to 1.6V quickly, then the system starts switching from 7kHz frequency at the beginning, the COMP voltage rises up gradually, and the inductor peak current also rises up. The LED current hence achieves a soft start without overshoot.
2 Constant Current Control
The FC2338 utilizes patent pending floating ground structure. The inductor current is sensed during the whole switching cycle, thus it achieves high precision output current control and also excellent line and load regulation. The LED current can be calculated by the equation: Rcs VIOUT REF≈ Where, VREF: Internal reference voltage Rcs: Value of the current sensing resistor
3 Feedback Network
The FB pin is used to detect output voltage, the OVP threshold voltage is 1.65V. The ratio of FB upper FC2338 2019. 10. 02 7/9Revision No : 0
resistor to lower resistor can be set as: 1.65FBL FBL FBH OVP R V R R V=+ Where, RFBL: The lower resistor of the feedback network RFBH: The upper resistor of the feedback network VOVP: Output over voltage setting point If the system have no OVP，this pin will be connected to GND.
4 Thermal Regulation
The FC2338 integrates thermal regulation function. When the system is over temperature, the output current is gradually reduced; the output power and thermal dissipation are also reduced. The system temperature is regulated and the system reliability is improved. The typical thermal regulation temperature is set to 140℃ internally.
5 Protection Functions
To improve the system reliability, FC2338 offers protection functions: When the LED is open circuit, the output voltage will gradually rise up. The output voltage is sensed by the FB pin when power MOSFET is turned off. When FB voltage reaches the OVP threshold, it will trigger fault logic and the system stops switching. When the LED is shorted circuit, the switching frequency will work under 7 kHz. Meanwhile, the output voltage is low and the VCC pin cannot be charged up by the output voltage, so the VCC pin voltage will gradually decrease and finally reaches the UVLO threshold. After the system enters into fault condition, the VCC voltage will decrease until it reaches UVLO threshold. Then the system will re-start again. If the fault condition is removed, the system will resume normal operation. saturated, the CS peak voltage will be relatively high. When CS voltage reaches the internal limitation (1.5V), the power MOSFET will be turned off instantaneously. This cycle by cycle current limitation can help protecting the power MOSFET, the inductor and the output diode.
6 PCB Layouts
The following guidelines should be followed in FC2338 PCB layout: Bypass Capacitor Put the bypass capacitor close to VCC pin, and loop compensation capacitor to COMP pin. Ground Path Keep a short and wide ground path for current sense resistor. The IC signal ground for COMP and FB components should be connected to the IC GND. The Area of Power Loop The area of main current loop should be as small as possible to reduce EMI radiation. FB Pin Put the divider resistor close to the FB pin as possible, and keep the trace away to the switching node. DRAIN Pin To increase the copper area of DRAIN pin for better thermal dissipation. When the output is short circuit or the inductor is FC2338 2019. 10. 02 8/9Revision No : 0
SOP-7 PACKAGE OUTLINE DIMENSIONS FC2338 2019. 10. 02 9/9Revision No : 0