Energy-saving lamp and electronic rectifier triode parameters selection guide - Power Circuit - Circuit Diagram

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

DFN1006 TP-RCLAMP3321P ESD Diode Low Capacitance

Brand AVX TPSE226M035R0125 Low impedance tantalum capacitor AVX 22

Electronic scale crystal oscillator 3.2*2.5mm 3225 16M (16.000MHZ) 12PF 10PPM 20PPM 30PPM

In the past, the positioning of the requirements for the energy-saving lamps and electronic ballast triode parameters was unclear. In addition to the conventional parameter requirements of BVceo, BVcbo, Iceo, hFE, Vces, Ic, etc., the low frequency tube has only the characteristic frequency requirement (generally on the order of several megabytes). However, the characteristic frequency is a requirement for linear amplification of the sine wave, and the triode switching parameter is not a concept with the switching operation state. In addition, due to the level of knowledge and the limitations of domestic hardware conditions, people have effectively prevented the effective control and identification of the parameters of the lamp triode. This paper attempts to summarize the choice of triodes for energy-saving lamps and electronic ballasts in order to fully understand the damage mechanism of triodes in the application process.
Complete power tolerance curve reduces triode heat loss loss factor hFE and storage time ts
The complete power margin curve power margin (SOA) is a region surrounded by a curve (Figure 1). When the voltage and current coordinate values ​​added to the transistor exceed the curve range, the transistor will be broken by power breakdown. In practical applications, some switching power supply line loads are inductive. After the triode is turned off, the self-induced potential anti-peak voltage generated by the inductive load is added between the CE poles of the triode. The triode must have enough SOA, BVceo and BVcbo values. Withstand such back pressure.

After the triode is operated in the circuit for a period of time, the line components will generate heat (including the heat of the tube itself), and the temperature rises continuously, resulting in an increase in the triode hFE, poor switching performance, and a decrease in secondary breakdown characteristics. Conversely, the tube heat is further increased, and such a vicious cycle eventually causes the triode to break down and burn. Therefore, reducing the heat loss of the triode itself is an important measure to improve the reliability of the triode.
Experiments show that the power consumption of the transistor off state is small; the dissipation of the conduction state accounts for a certain proportion, but the change is not large. Transistor dissipation mainly occurs in the transition period from saturation to off and from off to saturation, and has a great relationship with the selection of line parameters and the rise time tr and fall time tf of the triode.
In recent years, the industry-supplied triodes for energy-saving lamps and electronic ballasts have fully noticed the reduction of switching losses. For example, the domestic BUL6800 series products have greatly improved the switching loss performance of the products based on the optimized MJE13000 series.
In addition, controlling the magnetic ring parameters also helps to control losses. Because the change of the magnetic ring parameters will cause the change of the transistor Ib, affecting the rise and fall time of the triode. The triode over-drive can cause the triode to burn out severely, and the triode drive is insufficient, which may cause transient breakdown damage when the triode is cold-started.