Power-driven program COB MCOB TCOB Led T8 T5 lamps< br>cob, tcob,mcob, led ,tube, t5 ,t8, t12, t10, lights, lamps, manufacturer, distributor, wholesaler, factory review: As of 2013, China had more than nearly 80% of these are fluorescent T8 led tubes. Therefore, the design of cost-effective T8 led tube T5 COB MCOB TCOB Led lamp drive scheme, more conducive to replace the original fixture. Malicious solemn statement on this site are reproduced the original article, intentionally deleting the word Engineering COB MCOB TCOB Led< br>Supermarkets, shopping malls, hospitals, factories, offices, schools and hotels and other places of lighting required, there T8 lamp shadow . Data show that: As of 2013, China had more than nearly 80% of these are fluorescent T8. Therefore, the design of cost-effective T8 t10 T5 COB MCOB TCOB Led lamp drive scheme, more conducive to replace the original fixture.< br>For T8 T5 lamp application, Fujian Wanban Optoelectronics Technology Cp.,ltd (tcobled.com) developed SM7307, SM7302, SM7330B, SM7332PB other variety of driver chips, can achieve all T tube 8W to 48W of the program. The following combination of these products, T8 T5 program is described in detail.< br>A high-performance constant-current drive scheme SM7307 SM7302< br>SM7307 and SM7302 power is applied to different products of the same series, SM7307 apply to 8W to 18W T-pipe solutions, and SM7302 is suitable for 12W to 24W T-pipe solutions. Both are high-precision constant current driver switch, integrated high-voltage power switch, use BUCK topology, without any compensation elements, constant current accuracy of less than ¡À 3%; high pressure from the start and supply of patented technology, IC internal self power supply, no external auxiliary power supply; system efficiency up to 90%, with multiple protection COB MCOB TCOB Led open load, short circuit protection, high reliability, and high system BOM cost. SM7307 SM7302 typical system schematic shown in Figure 1.< br>SM7307 SM7302 uses patented constant current control technology, by limiting the peak current sense terminal CS current power switches, power control switch is closed; FB port detection inductor current zero crossing, the control switch is turned on, in order to determine the the level of current flowing through the peak value of the inductor to achieve a constant current output.< br>By DRAIN port via the internal JFET to VDD capacitor charging, the IC’s internal power supply voltage regulator circuit realization.< br>1.1 BOM table< br>Using SM7307 implemented 9W to 18W (VOUT: 75V ~ 150V, IOUT: 120mA) T8 COB MCOB TCOB Led tube scheme, power supply systems are typically the BOM (corresponding to the circuit diagram above) are shown in Table 1:< br>1.2 Test Data< br>In 180-264Vac input voltage range, constant current accuracy of this system is ¡À 1.5%; the average conversion efficiency of the system is greater than 90%, the test data of different input voltage and output load conditions as shown in Table 2:< br>1.3 PCB Layout Considerations< br>The PCB size is only 20 * 25mm, the circuit board real shot in Figure 2:< br>In PCB design, in order to ensure the performance of the system, we need to pay attention to the following points:< br>(1) IC’s GND GND need to shop copper, can enhance heat dissipation of the IC;< br>(2) as far as possible so that the main loop (current loop) traces short, do not FB, VDD pin is enclosed within the main loop;< br>(3) from the output to the FB terminal of the resistor R2 is recommended plug resistance;< br>(4) the system output capacitor values ??are the same, preferably electrolytic capacitors, chip capacitors second choice;< br>SM7302 is designed the same way as the SM7307, SM7307 only a power greater than the power.< br>Second, high power factor, cost-effective T8 T5 program SM7330B SM7332PB< br>SM7330B and SM7332PB belong to high power factor range of products, SM7330B apply external power transistor drive program, and is integrated 2N60 SM7332PB power tube. Both are BUCK topology, operates in critical conduction mode at full voltage 90Vac ~ 265Vac input voltage range, constant current accuracy of up to ¡À 5%, PF value greater than 0.9, with output open, short circuit protection features. By EFT, lightning surge and other reliability testing. SM7330B output power can cover 9W to 48W, its typical operating principle is shown in Figure 3: SM7330B on the system power, half sine wave voltage through the startup resistor to charge the capacitor VDD pin when VDD rises after the start threshold voltage, chip control circuit operates when the output voltage is established, VDD voltage from the output voltage of the power supply through a diode.< br>Chip sampling inductor current, using an internal error amplifier form a closed loop feedback network, resulting in high accuracy and high constant load regulation.< br>CS voltage and the reference voltage by the error amplifier transconductance amplifier, and an external capacitor integrator COMP. COMP terminal voltage to control the external power MOSFET is time to adjust the output current.< br>SM7332PB integrated power transistor 2N60, the maximum output power up to 20W, its typical output specifications for the 80V 180mA. Their physical maps, application schematic in Figure 4, Figure 5.< br>SM7332PB works with SM7330B, no longer tired. SM7332PB typical output specifications 80V 180mA basic electrical parameters, the conversion efficiency and power factor as shown in Table 3, Table 4 and Table 5.< br>Led cob mcob tcob T8 T5 driver program uses SM73XX series chip design, not only cost-effective but also by a variety of reliability testing and EMC certification is the best choice for T8 T5 drive scheme.