Modelling LED lamps in SPICE with thermal phenomena taken into account

Modelling thermal properties of large LED modules

“…To enable calculation of the value of internal temperature of each LED being a part of the LED module, it is indispensable to take into account the dependence of internal temperature of each diode on the power dissipated in the whole module [15,19,20]. The authors in their previous papers [5,9,16,21] proposed electro-thermo-optical models of LED modules taking into account selfheating phenomena and mutual thermal couplings, and verified them for small LED modules, whose diameter did not exceed 5 cm. In such models, temperature of the common base and internal temperatures of all diodes are used, whereas transient thermal impedances of all the diodes are the same.…”

“…In the lighting technique, both single power LED and LED modules can be used [1][2][3][4]. Usually, in LED lamps, round LED modules of the diameter not exceeding 4 cm are used [5]. Nowadays, large LED modules, whose area exceeds even 100 cm 2 , are also offered.…”

“…LED modules can accept different shapes and they can be situated on the Metal Core Printed Circuit Board (MCPCB) base with different thicknesses of the aluminum-layer. It is justified, that large LED modules contain from several to tens LEDs in order to limit the value of feeding current [5,[8][9][10][11][12][13]. Distances between each pair of LEDs in the module do not exceed several centimeters, which causes that mutual thermal couplings between diodes situated on the same basis occur [5,14,15].…”

“…It is justified, that large LED modules contain from several to tens LEDs in order to limit the value of feeding current [5,[8][9][10][11][12][13]. Distances between each pair of LEDs in the module do not exceed several centimeters, which causes that mutual thermal couplings between diodes situated on the same basis occur [5,14,15]. As was reported in the papers [14,16], an excessive increase in the value of forward current causes some thermal phenomena that result in a decrease in the luminous flux emitted by LEDs.…”

“…It is worth noting that temperature strongly influences characteristics, operating parameters * E-mail: k.gorecki@we.am.gdynia.pl and reliability of discrete semiconductor devices and modules, such as IGBT [17] and LED modules [5,9,18]. Therefore, the information about the value of internal temperature of semiconductor devices contained in the mentioned modules is very important.…”