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krakajax
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I am designing a 500mA source circuit using a npn and pnp transistors. How can I protect the pnp if the output is shorted to gnd. Both transistors are in common collector configuration.
The way you usually do short circuit protection is with a low-value current sensing resistor and feedback from that sensing resistor to spoil the input drive to your output circuit. You want to use a small enough value resistor so that it doesn't rob much power from your output capability, but large enough that the voltage across the resistor in overcurrent conditions is large enough to sense reliably. In fact, depending on the topology and complexity of your circuit, you will usually use a diode drop voltage across the sense resistor as the threshold where you start feeding back a signal to spoil the input drive.krakajax said:I am designing a 500mA source circuit using a npn and pnp transistors. How can I protect the pnp if the output is shorted to gnd. Both transistors are in common collector configuration.
Short to GND protection is a safety mechanism used to protect electronic components from damage caused by a short circuit to ground. It helps prevent excessive current flow and can prevent costly repairs or replacements.
Short to GND protection works by detecting when an electrical current is flowing to ground through a component that is not designed to handle it. Once detected, it will activate a protection circuit that limits the current flow, preventing damage to the component.
Short to GND protection is important because it helps ensure the safe and reliable operation of electronic devices. Without this protection, a short circuit to ground could cause damage to the component, leading to malfunctions or even fires.
The most common types of Short to GND protection include fuses, circuit breakers, and polymeric positive temperature coefficient (PPTC) devices. These devices can be incorporated into electronic circuits to provide protection against short circuits to ground.
Short to GND protection can be implemented in a circuit by using components that have built-in protection, such as PPTC devices. It can also be achieved by adding external protective devices, such as fuses or circuit breakers, to the circuit design.