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LED lighting market share shows an ever increasing trend. This is driven by some of the LED advantages, such as higher efficiency, wide range of colors, and longer lifetime. LED is a DC device, and to power it from AC supply, like in household or street lightings, a driver is required to convert AC to DC supply. In addition, LED driver is preferred to operate in constant current mode in order to avoid LED thermal runaway. Also the driver has to have high efficiency, low THD (total harmonic distortion), and comply with electromagnetic emission limits. In this paper, a prototype of primary-side-regulated AC-DC flyback LED driver has been implemented. It has a constant output current of 0.990A 0.012A across the output voltage 15.59V – 42.80V. Measurement results show that the achieved efficiency is up to 88.55%, current harmonics comply with IEC 61000-3-2, and conducted emission levels comply with CISPR 15.

A remote system for controlling and monitoring the temperature inside the compartment's infant incubator on a mobile device is developed. The system composed of an Arduino Uno, an HC 05 module, a DHT 11 sensor, a relay, and a heater. The system has advantages on providing more sterile compartment's environment and easier control/monitor infant incubator. The developed system is proven to be used for controlling and monitoring infant incubator remotely. The average temperature response of the developed system is 0.397 °C/mins, and maximum communication distance between the developed system and the mobile phone is 12.25 m.

This paper focuses on the Electro-Magnetic Interference Risk Analysis of medical devices via the evaluation of their susceptibility. Medical devices for supporting patients' life are frequently applied in vulnerable environments such as hospitals and surgery rooms. The susceptibility analysis is based on a GTEM testing method derived from ANSI C63.18 and is applied to three different medical devices, namely ECG, patient monitor and an infusion pump. Specific interference signals are generated simulating telecommunication devices, more specifically Wi-Fi, GSM, and PMR. The results showed that especially the signals transmitted by the PMR may affect the performance of medical devices.

Two important parts of wireless power transfer are transmitter circuit and receiver circuit. Previous research has been completed which use CMOS H-Bridge in transmitter and full wave rectifier in receiver. This paper presented simple design of transmitter circuit and optimization of receiver circuit in rectifier circuit with transient analysis and Fast Fourier Transform (FFT) from LT spice software. The simple transmitter circuit used an integrated circuit (IC) NE555 with push-pull as oscillator circuit and LC resonant, while the receiver circuit used LC resonant, rectifier circuit, CLC filter for smoothing direct current (DC) output and 500 Ohm as load. The circuit design had resonant frequency of 250 kHz on both of transmitter and receiver, which comply with Power Matters Alliance (PMA) standard. The optimization of rectifier circuit had been done by comparing output of power load when it used basic rectifier (full wave), voltage doubler (dickson circuit and Villard circuit) and voltage multiplier (cockcroft-walton circuit). The results showed the receiver with Dickson circuit as rectifier has the highest efficiency compared to other rectifier circuits with efficiency of 10.93 % when it used coupling coefficient of 0.99, because Dickson rectifier has resonant frequency that is closest to 250 kHz and the highest level power, compared to other rectifier circuits.