1. Renesas Electronics America Inc. © 2012 Renesas Electronics America Inc. All rights reserved. Increasing the Performance of PFC and LED Driver Applications

2. © 2012 Renesas Electronics America Inc. All rights reserved.2 Renesas Technology & Solution Portfolio

3. © 2012 Renesas Electronics America Inc. All rights reserved.3 Discrete and Integrated Power Products LED Backlight LCDs  SiC Schottky barrier diodes for very high switching speeds  3A to 30A, 600V parts available  SBD optimized for high switching speeds  Class-leading turn-off loss  High-speed, short-circuit rated, and low Vce(on) optimized using thin wafers  Multiple package options and bare die option available  Low voltage family optimized for Qgd x Rds(on)  Separate family optimized for pure Rds(on) performance  600V Super Junction MOSFETs for SMPS  Dr MOS solutions for > 93% peak efficiency, up to 1.5MHz  PFC ICs for solutions up to 98% peak efficiency  Smallest CSP packages for POL, Battery Charger and Fuel Gauge Applications  Current ratings from 0.8A to 30A rms  Voltage ratings from 600V to 1500V  Junction temperature to 150°C 30V-1500V in Application Optimized Processes SiC, Fast Recovery, SBD and Others Optimized for Highest Efficiency & Compactness 300V-1350V Discrete Devices Broad Line-up of Packages and Devices

4. © 2012 Renesas Electronics America Inc. All rights reserved.4 Challenge: Enable LED’s to reduce energy consumption towards lighting. The US has an installed base of 5 billion bulbs. These are primarily either incandescent or compact fluorescent Together, these consume 18% of total US electricity! LED retrofitting should reduce the energy requirement by half.* * DOE Estimates by 2030 ‘Enabling The Smart Society’

5. © 2012 Renesas Electronics America Inc. All rights reserved.5 Challenge: Designing efficient LED supplies presents circuit challenges: Compact conversion of AC line power to DC Efficiency > 85% PF > 0.9 Stringent harmonics, ripple, dimming, reliability and cost requirements. ‘Enabling The Smart Society’ Example from Lamp-wallpaper.com (vendor unknown)

6. © 2012 Renesas Electronics America Inc. All rights reserved.6 Solution: Renesas extends PFC product family for LED applications to develop single stage PFC buck circuit using a hi-side switch to replace incumbent low side switch topologies to improve performance across the requirement spectrum ‘Enabling The Smart Society’

7. © 2012 Renesas Electronics America Inc. All rights reserved.7 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch improves upon incumbent topologies Results and data Summary Q & A Agenda

8. © 2012 Renesas Electronics America Inc. All rights reserved.8 What is the Retrofit Market? The US has 5 billion light bulbs installed, and about 2 billion light bulbs are sold in the US each year! Replace this And this With these &

9. © 2012 Renesas Electronics America Inc. All rights reserved.9 Why Replace Incandescent and CFL Bulbs? Efficiency Standard Incandescent CFL 5 – 26 W CFL 27 – 40 W LED 2007 - 2010 LED in Development ‘10 IESNA Lighting Handbook, Ninth Edition p 26-3 and Wikipedia

10. © 2012 Renesas Electronics America Inc. All rights reserved.10 Why Replace Incandescent and CFL Bulbs? Efficiency Lifetime 25K hours per LED Incandescents CFLsLED 1K hours per 10K hours per25K hours per How many incandescent and CFL bulbs to reach 25K hours? OSRAM Online Study 4.08.2009

11. © 2012 Renesas Electronics America Inc. All rights reserved.11 Why Replace Incandescent and CFL Bulbs? Efficiency Lifetime Maintenance Costs Online e-conolight.com brochure

12. © 2012 Renesas Electronics America Inc. All rights reserved.12 Why Replace Incandescent and CFL Bulbs? Efficiency Lifetime Maintenance Costs From EDN Joke Contest

13. © 2012 Renesas Electronics America Inc. All rights reserved.13 Why Replace Incandescent and CFL Bulbs? Efficiency Lifetime Maintenance costs Regulatory compliance Energy Independence and Security Act of 2007 ● Requires ~ 25 percent more efficiency for household light bulbs. ● Effectively phases out household incandescent bulbs (but not CFL’s and specialty lamps). ● Was signed by then President Bush in 2007.

14. © 2012 Renesas Electronics America Inc. All rights reserved.14 Why Replace Incandescent and CFL Bulbs?

15. © 2012 Renesas Electronics America Inc. All rights reserved.15 Why Replace Incandescent and CFL Bulbs? Question: Why regulate power factor for LED lighting down to 25W, when other equipment less than 75W is exempted from Power Factor regulations? Answer: Related to the 5B Bulbs installed in the US, 18% of US electricity consumption; each US households averages 40 active bulbs, so in aggregate low PF LEDs will contribute a lot of harmonic current to the AC lines in even residential buildings.

16. © 2012 Renesas Electronics America Inc. All rights reserved.16 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch improves upon incumbent topologies Results and data Summary Q & A Agenda

17. © 2012 Renesas Electronics America Inc. All rights reserved.17 Efficiency Efficiency = Useful Power Output / Total Power consumed Often and herein denoted by Greek symbol 

18. © 2012 Renesas Electronics America Inc. All rights reserved.18 Linear Loads Linear load: A load in which a sinusoidal voltage draws a sinusoidal current with the same frequency. Examples Resistor: V= I*R Resistive Loads – Incandescent Bulb – Electric Heater

19. © 2012 Renesas Electronics America Inc. All rights reserved.19 Linear Loads Question: Resistive loads, defined by Ohm’s law, are clearly, linear. How about purely inductive or capacitive load, is it linear as well?

20. © 2012 Renesas Electronics America Inc. All rights reserved.20 Non-Linear Loads Non-linear load: The current flow is non-proportional to the applied voltage.

21. © 2012 Renesas Electronics America Inc. All rights reserved.21 Linear Loads Question: Resistive loads, defined by Ohm’s law, are clearly, linear. How about purely inductive or capacitive load, is it linear as well? Answer: Yes!

22. © 2012 Renesas Electronics America Inc. All rights reserved.22 Real Power P AC (Watts) = V rms * I rms = I 2 rms *R V(t) R

23. © 2012 Renesas Electronics America Inc. All rights reserved.23 Reactive Power R = Zero Ohms. So real power transfer is zero, instead the circuit has a reactive power. Q = I 2 rms * Z Units = Volt * Amperes Reactive  Common Reactive Components V(t) L

24. © 2012 Renesas Electronics America Inc. All rights reserved.24 Apparent Power  Real Power (P) = Watts = I 2 R Reactive Power (Q) = volt*amperes reactive = I 2 (X L -X C ) Apparent Power (S) = volt*amperes = I 2 Z

25. © 2012 Renesas Electronics America Inc. All rights reserved.25 Power Factor: Incomplete Definition  Real Power (W) Reactive Power (Q) Apparent Power (S) Power factor = Real Power / Apparent Power = COS ()

26. © 2012 Renesas Electronics America Inc. All rights reserved.26 Power Factor: Incomplete Definition The angle between V & I is zero, so PF = COS ( 0 ) = 1 ? Wrong: In fact we need another term, THD, to the PF equation Non-linear load example: SMPS.

27. © 2012 Renesas Electronics America Inc. All rights reserved.27 Harmonic Current Harmonic current: Harmonic currents are integer multiples of the fundamental frequency (e.g. 60 Hz in the US). Harmonic currents are created by non-linear loads. by converting the signal on the fundamental supply frequency. 120 Hz (2 nd harmonic), 180 Hz (3 rd harmonic), 240 Hz (4 th harmonic)…

28. © 2012 Renesas Electronics America Inc. All rights reserved.28 Total Harmonic Distortion I 1 : RMS value of AC current fundamental I n: RMS value of AC current nth harmonic Harmonic current: Total harmonic distortion quantifies the magnitude of the harmonics:

29. © 2012 Renesas Electronics America Inc. All rights reserved.29 This current wave is distorted by odd order (3 rd, 5 th, 7 th …) harmonic current PF << 1 AC voltage (sinusoidal) AC current 0 1 2 3 4 5 6 3 rd 5 th 7 th 9 th Order of harmonic current Harmonic current [A] Fundamental = 50 Hz (150 Hz)(250 Hz)(350 Hz)(450 Hz) Waveform Distortion by Harmonic Currents

30. © 2012 Renesas Electronics America Inc. All rights reserved.30 A Complete Power Factor Definition Power factor, a complete definition: Power Factor (PF)= Real Power / Apparent Power = COS () * Irms(fundamental) / Irms = COS () * 1/(1+THD) 2

31. © 2012 Renesas Electronics America Inc. All rights reserved.31 Example: Incandescent Light Bulb AC voltage (AC 100 V) +100 V -100 V AC current (AC 0.5 A) +0.5 A -0.5 A In phase & Proportional Power Factor = 1

32. © 2012 Renesas Electronics America Inc. All rights reserved.32 AC current controlled by dimmer With a dimmer, even an incandescent bulb PF << 1 Example: Incandescent Light Bulb with Dimmer

33. © 2012 Renesas Electronics America Inc. All rights reserved.33 LED Characteristics I*V curve for a diode: For bright LED’s On voltage will be ~ 3.3V Intensity will be ~ 60 lm/Watt – Compare to ~ 20lm/W for an incandescent bulb Intensity will, approximately, scale linearly with current Drawing from Wikipedia

34. © 2012 Renesas Electronics America Inc. All rights reserved.34 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch Results and data Summary Q & A Agenda

35. © 2012 Renesas Electronics America Inc. All rights reserved.35 LED Drive Requirements for Retrofit Market > 85% PF > 0.9 THD < 20% Leading Edge Dimming Compatibility Trailing Edge Dimming Compatibility Maintenance Costs Regulatory Compliance

36. © 2012 Renesas Electronics America Inc. All rights reserved.36 LED Driver Circuit Background Buck-boost low side filter Driver IC Common LED drive circuits combine CRM PFC function With a low-side MOS Gate Drive circuit

37. © 2012 Renesas Electronics America Inc. All rights reserved.37 LED Driver Circuit Background Gate off timing Vac Iac IL Ton Toff COMP RAMP GD Ramp level shift v(t) di(t)= L dt filter IC Buck-boost low side PFC operation is CRM

38. © 2012 Renesas Electronics America Inc. All rights reserved.38 LED Driver Circuit Background Amplifier Gate Drive ramp Gate Smoothing Peak currentPhase compensation R2A20135 Gate off timing Vac Iac IL Ton Toff COMP RAMP GD Ramp level shift v(t) di(t)= L dt An alternate is high side gate drive (High side driver IC will float versus ground, and be more susceptible to noise.)

39. © 2012 Renesas Electronics America Inc. All rights reserved.39 Hi-Side Drive Merits are Efficiency and Cost V L = L* (di/dt) Gate off timing Vac Iac IL Ton Toff COMP RAMP GD Ramp level shift v(t) di(t)= L dt

40. © 2012 Renesas Electronics America Inc. All rights reserved.40 Hi-Side Drive Merits are Efficiency and Cost

41. © 2012 Renesas Electronics America Inc. All rights reserved.41 Hi-Side Drive Merit includes Current Precision MOS high-side drive Diode current I[A] t[s] MOS Current Diode Current Driver IC MOS current Both MOS current and Diode current Controlled by CS resistor !!! Driver IC MOS Current Diode Current f Diode current I[A] t[s] MOS low-side drive Only MOS current Controlled by CS resistor !!! As inductor value changes, LED current changes As inductor value changes, LED current isn ’ t pronounced 6%10% High side drive has more precise current accuracy

42. © 2012 Renesas Electronics America Inc. All rights reserved.42 Hi-Side Drive Merit includes Current Precision Question: What typical circumstance may change the inductance value? Answer : Temperature change. L =    r N 2 A / l    permeability of free space  r  rel permeability of core N = number of turns A = cross section of coil l = length of coil High side drive has more precise current accuracy

43. © 2012 Renesas Electronics America Inc. All rights reserved.43 Hi-Side Drive Merit includes Current Precision MOS high-side drive Diode current I[A] t[s] MOS Current Diode Current Driver IC MOS current Both MOS current and Diode current Controlled by CS resistor !!! Driver IC MOS Current Diode Current Diode current I[A] t[s] MOS low-side drive Only MOS current Controlled by CS resistor !!! As inductor value changes, LED current changes As inductor value changes, LED current isn ’ t pronounced Better! 6%10% High side drive has more precise current accuracy

44. © 2012 Renesas Electronics America Inc. All rights reserved.44 Complete Circuit Implementation

45. © 2012 Renesas Electronics America Inc. All rights reserved.45 Power Factor Tradeoff Considerations Power Factor improvement options Reduce input capacitor to decrease charge current pulse Reduce V F (load) to decrease zero conduction period length.

46. © 2012 Renesas Electronics America Inc. All rights reserved.46 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch improves upon incumbent topologies Results and data Summary Q & A Agenda

47. © 2012 Renesas Electronics America Inc. All rights reserved.47 PF>0.9 Circuit Performance: Power Factor Higher than 0.9 over a 90Vac to 132Vac input range

48. © 2012 Renesas Electronics America Inc. All rights reserved.48 η>85% Circuit Performance : Efficiency Higher than 85% over a 90Vac to 132Vac input range

49. © 2012 Renesas Electronics America Inc. All rights reserved.49 THD<20% Circuit Performance: THD Under 20% over a 90V to 132Vac input range

50. © 2012 Renesas Electronics America Inc. All rights reserved.50 T1 T2 time ratio[%] = 100×(T2/T1) Bridge Voltage Circuit Performance : Leading Edge Dimming Dimmer type WN575159(Panasonic denko 500VA) Dimming from nearly 0% to 100% with 100 to 120 Vac

51. © 2012 Renesas Electronics America Inc. All rights reserved.51 Dimmer type DVELV-300P(LUTRON 300W) Min-Max of time ratio is the operation range of dimmer control Circuit Performance : Trailing Edge Dimming T1 T2 time ratio[%] = 100×(T2/T1) Bridge Voltage 4% 10% - 100% area Dimming from 4% to 100% with 100 to 120 Vac

52. © 2012 Renesas Electronics America Inc. All rights reserved.52 Demo Board Line-up T1 T2 time ratio[%] = 100×(T2/T1) Bridge Voltage 4% 10% - 100% area Improvement in design efficiency, inventory management cost reduction. *Input range : 90 to264V *PF>0.9 within 90 to264V *efficiency>85% within 90 to264V *Iout ripple<30% within 90 to264V *THD<30% within 90 to264V High efficiency dimmable solution. *Input range : 90 to132V *PF>0.9 *efficiency>85% *Iout ripple<30% *THD<30% Improvement in design efficiency, inventory management cost reduction. *Input range : 90 to264V *PF>0.97 within 90 to264V *efficiency>8 １ % within 90 to264V *Iout ripple<30% within 90 to264V *THD<30% within 90 to264V

53. © 2012 Renesas Electronics America Inc. All rights reserved.53 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch improves upon incumbent topologies Results and data Summary Q & A Agenda

54. © 2012 Renesas Electronics America Inc. All rights reserved.54 Summary Potential benefits of LED retrofit lighting include Halving US energy consumption for lighting Reducing maintenance costs by 80%+ Design challenges of LED retrofit lighting include Meeting PF regulatory requirements Meeting size and efficiency constraints Achieving compatibility with existing dimmers PFC with driver for high side switch is an excellent solution Has inherent efficiency and cost advantages Enables excellent dimming performance Meets PF requirements

55. © 2012 Renesas Electronics America Inc. All rights reserved.55 Summary Potential benefits of LED retrofit lighting include Halving US energy consumption for lighting Reducing maintenance costs by 80%+ Design challenges of LED retrofit lighting include Meeting PF regulatory requirements Meeting size and efficiency constraints Achieving compatibility with existing dimmers PFC with driver for high side switch is an excellent solution Has inherent efficiency and cost advantages Enables excellent dimming performance Meets PF requirements

56. © 2012 Renesas Electronics America Inc. All rights reserved.56 LED retrofit opportunity and requirements Pertinent terms and definitions Single stage PFC buck circuit with high side switch improves upon incumbent topologies Results and data Summary Q & A Agenda

57. © 2012 Renesas Electronics America Inc. All rights reserved.57 Questions? Questions?

58. © 2012 Renesas Electronics America Inc. All rights reserved.58 Challenge: Enable LED’s to reduce energy consumption towards lighting by meeting circuit challenges. Today lighting consumes 18% of total US electricity! LED retrofitting should reduce the energy requirement by half. Design challenges for size, efficiency, PF, cost must be overcome. Solution: Renesas extends PFC product family for LED applications to develop single stage PFC buck circuit using a hi-side switch to replace incumbent low side switch topologies to improve performance across the requirement spectrum ‘Enabling The Smart Society’

59. Renesas Electronics America Inc. © 2012 Renesas Electronics America Inc. All rights reserved.