The holding current in a Silicon Controlled Rectifier (SCR) is the minimum current that must flow through the device to maintain conduction after it has been triggered into the conducting state. Once an SCR is triggered by a sufficient gate current and enters the conducting mode (turned on), it will continue to conduct even if the gate current is removed, as long as the anode current remains above the holding current threshold. If the anode current drops below this threshold, the SCR will turn off until it is triggered again. The holding current ensures stable operation and prevents unintentional turn-off due to minor fluctuations in current.
In an SCR, the latching current (the minimum current required to initially trigger the device into conduction) is typically greater than the holding current. Latching current is necessary to overcome the SCR’s forward voltage drop and initiate conduction. Once triggered, the device will continue to conduct as long as the anode current remains above the holding current threshold. Therefore, while latching current starts the conduction, holding current maintains it during normal operation.
The holding current for a relay refers to the minimum current required to keep the relay’s contacts in the closed position after initial activation. When a relay coil is energized, it pulls its contacts closed to complete a circuit. The holding current ensures that the contacts remain closed even after the initial coil energization is removed, maintaining continuity in the circuit. This characteristic is crucial in relay applications where sustained operation without continuous coil activation is required.
The holding current of a TRIAC (Triode for Alternating Current) is the minimum current required to keep the device conducting once it has been triggered into conduction mode. Similar to an SCR, a TRIAC is a semiconductor device that can switch AC currents. Once triggered by a gate current, the TRIAC conducts current in both directions until the current drops below the holding current threshold. This ensures that the TRIAC remains in the conducting state throughout the AC cycle, providing efficient switching and control of AC loads.
In a DIAC (Diode for Alternating Current), the holding current refers to the minimum current at which the device can maintain conduction after it has been triggered into conduction by exceeding its breakover voltage. The DIAC is a bidirectional device that conducts current in either direction when triggered. Once the current through the DIAC drops below the holding current threshold, it ceases to conduct until triggered again. The holding current ensures stable operation of the DIAC in AC circuits, allowing it to perform reliably in triggering other semiconductor devices like TRIACs for controlled switching applications.
What is the difference between inter and intra handover in LTE? In LTE, intra handover refers to a device switching…