Application Notes

Silicon Carbide Schottky diodes feature a high reverse voltage (650 V ... 1200 V) combined with an extremely low "reverse recovery" better say capacitive charge and thus discharging time. That makes these parts ideally suited for all applications, where high voltage levels are switched at very high frequencies. Typical applications include charging systems for electric vehicles (EV), solar inverters or telecom power supplies.

Rectifier diodes in switching applications dissipate power due to conduction and switching losses. This application note describes the power dissipation mechanisms and provides a selection of Fast Recovery Rectifiers that minimize switching losses and thus increase efficiency.

The Enable input (EN), available in positive and negative logic, turns the device on and off by an external signal. Active-high logic activates the device when the voltage at the EN-input exceeds the high-logic threshold. The active-low logic switches the device off when the EN-voltage falls below the logic low threshold. The EN-function is an import- ant feature when sequencing power supplies in multi-rail systems.

When the LDO is turned off and connected to the battery system, the input current will be limited, usually up to 1 µA. This Shutdown current is commonly confused with the quiescent current which is the current drawn by the device when it is enabled and opera- ting with no load. Both shutdown and quiescent current are important parameters when realizing long battery lifetimes in portable devices.

Current Limiting Diodes (CLD), also known as Constant Current Regulators (CCR), can be used to drive LED strips used in modern lighting systems. They can be easily switched in parallel in order to achieve any driving current required for the used LED type. Their disadvantage is temperature dependency of regulation current, as well as inability to provide a dimming functionality. There is a wide variety of LED driving ICs available, using pulse width modulation (PWM) for dimming LED lamps. Switching frequency is high enough to avoid any flickering of the lamps. Dimming level is either taken from the traditional phase-angle-controlled mains, or from analogue/digital signals provided from smart home systems.

Diotec offers several semiconductor solutions dedicated for Smart Meter needs. Take the example of input rectifier stage; it is connected directly to the landline and thus highly affected by excessive voltage peaks caused by lightning strikes. No matter if you prefer single diodes connected in series, avalanche rated rectifiers or Diotec‘s brand new 3000 V diodes: we offer you any solution according to your requirements.

This application note is about choosing suitable diodes for high-speed signal interfaces. One of the major industry trends towards smaller chip size and higher data rate de- creases chip tolerance to any voltage transient surge events. Therefore, electrostatic discharge (ESD) protection diodes play a bigger role than before. In addition, designers are no longer relying on the internal capability of the semiconductor components, but on an external protection added to eliminate the risk against any voltage transient events.

This application note explains the mechanisms of heat transfer in semiconductor components along with Diotec’s datasheet parameters of 1ph and 3ph Bridge Rectifier. It further describes a way to determine whether a bridge is suitable for a given output current and ambient respectively case temperature.

This application note provides an overview of three accurate and cost-optimized solutions for a wide range of temperature sensing applications.