Contents
What is thermal calculation?
Thermal calculation requires information on the IC loss power, the thermal resistance or thermal characteristics parameter of the package, the ambient temperature, and the temperature at the center of the package surface.
How do you calculate the power dissipation of a voltage regulator?
Thermal calculation for a linear regulator Power loss is calculated in the same manner as the efficiency calculation: simply multiply the input/output voltage difference by the input current.
Why thermal shutdown is applied to voltage regulator?
The thermal shutdown (TSD) function monitors the chip temperature of an LDO regulator and turns off its output to prevent chip degradation or destruction in the event of an excessive rise in chip temperature caused by a shorted load, an output-to-GND short-circuit, a rise in the ambient temperature, or self-heating.
What is dropout voltage in LDO?
Dropout voltage is the input-to-output differential voltage at which the circuit ceases to regulate against further reductions in input voltage; this point occurs when the input voltage approaches the output voltage. Figure 1 shows a typical LDO regulator circuit.
What is the formula for calculating thermal capacity?
“The thermal capacity of a body is the heat necessary to raise the temperature of the body by one degree.” Thermal capacity = mass of body × specific heat. Find the water equivalent of a copper container having a mass of 7·2 lb. The specific heat of copper is 0·091.
What is unit of thermal resistance?
The SI unit of absolute thermal resistance is kelvins per watt (K/W) or the equivalent degrees Celsius per watt (°C/W) – the two are the same since the intervals are equal: ΔT = 1 K = 1 °C.
What is line regulation with its formula?
Line Regulation is the change in output voltage due to variation of the input voltage with all other factors held constant. It is expressed as a percent of the nominal output voltage. A power supply with tight line regulation delivers optimum voltages throughout the operating range.
What is a thermal shutdown?
The thermal shutdown function is a circuit that prevents deterioration and breakdown due to a significant increase in ambient temperature and heat generation of the device itself due to an unintended large current load.