A previous Idea for Design described a technique for protecting the “pass” transistor in a current-limiting circuit against excessive power dissipation (see “Fault-Protected Current Limiter Keeps Its ...
The simple current-limiting load switch shown in Figure 1 will be familiar to most readers. In this circuit, a high level signal applied to the input switches on MOSFET Q2, which energizes the load.
Hot-swap circuits are among those measures put in place to protect equipment or personnel, or both. Some power supplies, for example, have built-in and adjustable current limiting (standard in ...
A silicon controlled rectifier or semiconductor controlled rectifier (SCR) is a four-layer solid-state current -controlling device. The name "silicon controlled rectifier" is General Electric 's trade name for a type of thyristor.
If the SCR fails to latch, the problem may be with the load and not the SCR. A certain minimum amount of load current is required to hold the SCR latched in the “on” state.
SCRs are constructed from silicon and are most commonly used for converting AC current to DC current (rectification), hence the name Silicon controlled rectifier. They are also used in other applications such as regulation of power, inversion, etc.
An SCR is a four-layer PNPN silicon semiconductor device. It has three external terminals (anode, gate, and cathode) and uses the alternative symbols of Figure 1 (a) and has the transistor equivalent circuit of Figure 1 (b).
Thyristors or silicon controlled rectifiers, SCRs - the names are used interchangeably - may appear to be unusual electronics components in many ways, but they are particularly useful for controlling power circuits.