RT7306 Evaluate Report for RFID Dim Bulb EVB (Buck-Boost) ACDC BU / SLM Division Apr . 2015 http://www.richtek.com/LED CONFIDENTIAL RT7306 Brief introduction RT7306 is an active power factor correction controller specifically designed for using as a constant current LED driver. Supporting: Isolation: PSR mode Non-isolation: Buck-Boost mode Applications AC/DC LED lighting driver for Smart dimming function ……… 2 CONFIDENTIAL RT7306 Features Primary-Side Regulation PWM Controller and High PF LED Driver • Primary Side Regulation(PSR) • Power Factor Correction(PFC) • Compatible with Analog Dimming • Built-in HV start-up Device • Critical conduction mode(CRM) • Max/Min switch frequency clamping • Max/Min on time limitation • THD Optimization • Input Voltage Feed-Forward Compensation 3 CONFIDENTIAL RT7306 Advantage • Universal input voltage. (90Vac~264Vac) • Tight LED current regulation. • No shunt regulator and photo to achieve the 2 nd regulation. • Protection: a. LED Open-circuit protection b. LED Short-circuit protection c. Output diode short-circuit protection d. Vdd under/over voltage protection e. Over temperature protection f . Cycle-by-cycle current limitation g. Excellent PF and THD. 4 CONFIDENTIAL Circuit 5 CONFIDENTIAL Electrical Performance 6 CONFIDENTIAL Efficiency Efficiency 90% 85% 80% 75% 70% 65% 60% 90 110 132 180 200 220 240 264 Vin_ac(V) 7 CONFIDENTIAL Power Factor PF 1.00 0.95 0.90 0.85 0.80 0.75 0.70 90 110 132 180 200 220 240 264 Vin_ac(V) 8 CONFIDENTIAL Current regulation I_out(mA) 300 290 280 270 260 250 240 230 220 210 200 90 110 132 180 200 220 240 264 Vin_ac(V) 9 CONFIDENTIAL Load regulation I_out(mA) 300 280 260 240 110V 220 220V 200 30 32 34 36 V_out(V) 38 40 10 CONFIDENTIAL RFID Dimming Performance 300.0 DIM VS RF dim range 250.0 100.0 0.00 90Vac 220Vac 264Vac 50.0 0.50 110Vac V_Dim [V] 150.0 I-LED [mA] 200.0 RF Dim range [%] 100 90 80 70 60 50 40 30 20 10 0 1.00 1.50 DIM VS RF dim range 2.00 2.50 0.0 0 10 20 30 40 50 60 70 80 90 100 RF Dim [%] 3.00 3.50 11 CONFIDENTIAL PCB layout Top Trace Bottom Trace 12 CONFIDENTIAL Demo board photo LED- L LED+ N Aerial N LED+ L LED- PCB No : PCB018_V1 13 CONFIDENTIAL BOM Item Location Value Type 1 F1 7R5 / 1W (DIP) 2 VR1 TVR07471 D=7mm (DIP) 3 L1, L2 1.5mH DR0608 4 T1 Lp=1950uH EE1310 5 BD1 ABS10 Mini-Dip 6 D1 RS1M D-SMA 7 D2, D5 TBAV21W SOD-123 8 D3 CDBB3200 D-SMB 9 D4 T1N4148W-H SOD-123 10 Q1 ISU04N65A TO-251 11 U1 RT7306 SOP-8 12 U2 RT9058-50GV SOT-23 14 CONFIDENTIAL BOM Item Location Value Type 13 U3 FI-MM6600 --- 14 RL1, RL2 4.32K 0805 15 R3 10K 1206 16 R5 150K 1206 17 R6 47R 0805 18 R7 909R 0805 19 R8 3R 1206 20 R9 3R 1206 21 R10 80.6K 0603 22 R11 9.1K 0603 23 R12, R17 10R 0603 24 R13 300K 0603 15 CONFIDENTIAL BOM Item Location Value Type 25 R14 453K 0603 26 R15 47R 1206 27 R16 56K 0805 28 CX1, C1 0.1uF/450V (DIP) 29 C3 22nF/10V 0603 30 C4 1uF/10V 0603 31 C5 2.2nF/1KV 1206 32 C7 2.2uF/25V 0805 33 C8 100pF/1KV 1206 34 C19 4.7nF/1KV 1206 35 EC1 10uF/50V D=5mm (DIP) 36 EC2 220uF/50V D=10mm (DIP) 16 CONFIDENTIAL BOM Item Location Value Type 37 EC3 100uF/35V D=6.3mm (DIP) Total :42pcs 17 CONFIDENTIAL Transformer 18 CONFIDENTIAL Power Component Stress Voltage Test condition: 264Vac input / 36V,260mA output Stead state Location Max rating (V) Measure De-rating Q1 650 564 86.7% D1 200 174 87% Transient State Location Max rating (V) Measure De-rating Q1 650 548 84.3% D1 200 166 83% 19 CONFIDENTIAL Start up waveform Vac_in = 90V T_start up =196ms Vac_in = 264V T_start up =132ms CH1: I-LED , CH2: VCC , CH3: V-LED , CH4: V-AC LINE 20 CONFIDENTIAL LED open protection Vac_in = 90V CH1: VCC , CH2: V-ZCD , CH3: V-OUT Vac_in = 264V CH1: VCC , CH2: V-ZCD , CH3: V-OUT When LED open , the output keeps rising and causing the VZCD rising accordingly. If Vzcd trigger the protected level(2.9V~3.3V), the IC latch down. IC will be auto-restarted when the output is recovered. 21 CONFIDENTIAL LED Short protection Vac_in = 90V CH1: VCC , CH2: V-CS , CH3: V-OUT Vac_in = 264V CH1: VCC , CH2: V-CS , CH3: V-OUT When LED short , the output level is 0V and the Vcs will rise to trigger the protected function. IC will be auto-restarted when the output is recovered. 22 CONFIDENTIAL Harmonic(IEC61000-3-2) 110V input Class C : Pass Class D : Pass 23 CONFIDENTIAL Harmonic(IEC61000-3-2) 230V input Class C : Pass Class D : Pass 24 CONFIDENTIAL Conduction-EMI 110V-LPass 110V-N Pass 25 CONFIDENTIAL Conduction-EMI 230V-LPass 230V-N Pass 26 CONFIDENTIAL Radiation-EMI 110V-V Pass 110V-H Pass 27 CONFIDENTIAL Radiation-EMI 230V-V Pass 230V-H Pass 28