ELE Times December 2016 Electronics News in India | Online Electronics Mag | Page 36

Cover Story
efficiency of >84% for entire EU range and has very low standby
power consumption (<0.5W). Although dedicated pulse width
modulation (PWM) dimming dedicated pin is not available on
HVLED815PF IC but PWM dimming become possible in this
design. The depth of dimming at 2.5% level of output power. The
board communicates with utility even at switch OFF condition
thanks to the offline auxiliary power supply design which works
even in LED OFF condition. The SPBTLE-RF (Bluetooth Low Energy,
v4.1, network processor module with integrated RF section and
FCC certified) and STM32L051 (ultra-low power Microcontroller)
takes care of the connectivity and features such as remote
control, ON and OFF with the help of Android application.
There are several other features like including multiple board
control using single interface. For a typical home, installed with
several LED light fixtures, it is a precedent to save on electricity
bills with added luxury. Table 1 shows the specification of smart
home lighting system and Figs.3-8 show the test results of the
LED driver.

Fig.4 THD value with input voltage variation

Fig.5 Current regulation with input voltage variation
Fig.2 Smart home lighting system hardware and App
Table 1: Specification of smart home lighting system
Parameter

Value

Input Voltage

185VAC -275VAC, 50Hz

PF

>0.95

THD

<20%

Current Regulation

<±1%

Efficiency

>84%

Dimming

≤2.5%

Power Rating Output

12W

LED Load

32V, 330mA

Fig.6 Efficiency variation with input voltage

Fig.7 Harmonic current measurement plot
Fig.3 Power factor value with input voltage variation

ELE Times | 36 | December, 2016