Power Electronics
Dissipating Heat from Resistors Resistors convert electrical energy into heat energy. The power rating of a resistor defines the amount of power that can be safely dissipated by the resistor without exceeding temperature limits. Excess heat causes cumulative damage, changing the resistor’s properties and eventually leading to complete failure. Managing heat dissipation is critical when…
What is USB Type-C? The USB Type-C connector and cable specification was developed to create a universal connector for transmitting both data and power. The connector itself features a reversible design that allows both upside down and right-side up plug orientations. This reversible connector design provides ease of use for consumers struggling with cable orientation….
Understanding Resistor Materials Carbon Composition Resistors Carbon composition resistors consist of ceramic cylindrical bodies with carbon and binding material mixtures inside. The carbon and binding agent composite displays non-metallic conductive properties that impede electric current flow. By adjusting the ratio of conductive carbon to insulating binder, the resistivity can be controlled. Higher relative carbon content…
Ensuring Reliable Operation During Input Transitions A key design consideration for dual-input power systems is ensuring smooth, reliable operation when transitioning between the two input power sources. Sudden transitions between dissimilar inputs can cause temporary disruptive oscillation or repeated toggling between inputs if not carefully addressed. Hysteresis and intentional delay can be added to the…
What is Reverse Current Flow? Reverse current flow occurs when current flows from the output back into the input of a power supply. This can happen when multiple power supply units (PSUs) are connected in parallel, a configuration known as OR-ing, in order to provide redundancy or increased load capacity. If one PSU fails or…
Voltage Regulation Challenges in Multi-Source Systems The integration of renewable energy sources like solar and wind introduces significant variability and uncertainty into power systems. Fluctuating power generation from these intermittent sources leads to voltage fluctuations that propagate through the network. At the same time, load demand also varies drastically depending on consumer usage patterns. Maintaining…
Understanding BJT Reverse Active Mode Bipolar junction transistors (BJTs) are typically operated in forward active mode, where base current controls collector current flow. However, BJTs exhibit an unconventional operating mode called reverse active mode, where the roles of collector and emitter are reversed. In reverse active mode, the conventional collector operates as the emitter, emitting…
Understanding Reverse Active Mode Operation Bipolar junction transistors (BJTs) typically operate in forward active mode, where a positive base current flows to forward bias the base-emitter junction and create a collector-emitter current path. However, BJTs can also be operated in reverse active mode, by reversing the current flow directions. In reverse active mode, the emitter-base…
What is the Overlooked Voltage? The overlooked voltage, also known as the base width modulation voltage or back-gate voltage, refers to the voltage generated across the base region of a bipolar junction transistor (BJT) under active operation. This small voltage, typically ignored in basic transistor models, develops due to modulation of the base width caused…
The Constant Current Issue with LEDs LEDs or Light Emitting Diodes require a constant current flow through the junction to produce consistent illumination. Driving LEDs with a fixed voltage can result in unstable brightness as the LED warms up and the forward voltage drop changes. Connecting LEDs directly to power rails or variable voltage supplies…
