Contents
How can diodes be used to protect circuits?
What is is a Protection Diode? A protection diode used in any circuit that allows the flow of current in the forward direction, because the current will not flow in the reverse direction. It protects the components which are responsive to the flow of current through them in the wrong direction.
What is the purpose of a diode in a circuit?
A diode is a semiconductor device that essentially acts as a one-way switch for current. It allows current to flow easily in one direction, but severely restricts current from flowing in the opposite direction.
Do diodes have a resistance?
Ideally speaking, a diode is expected to offer zero resistance when forward biased and infinite resistance when reverse biased. However, no device can ever be ideal. Thus, practically speaking, every diode is seen to offer a small resistance when forward biased, and a considerable resistance when reverse biased.
What should I look for in a TVS diode?
TVS diodes come in all different flavors, but there are three key parameters. First, the maximum reverse standoff voltage. This is the working voltage. For USB, you’ll want to be very close to 5V. The next thing you’ll want to look at is the clamping voltage.
What are the ISO standards for surge protection?
There are specific standards to address surge protection for the automotive environment, including ISO 7637-2 and ISO 16750, while different countries have their own local standards. Figure 1 shows the shape of the test pulses on the 12V power rail defined by these two standards.
Which is the best device for transient voltage suppression?
The TVS is a solid-state device, which provides a low-impedance path to earth for a transient voltage surge, but a high-impedance path at all other times.
Why are transient voltages important in integrated circuits?
Transient voltages are an ever-present threat to sensitive integrated circuits, and in automotive applications they are unavoidable. The TVS is the right component, in many cases, to provide protection against surges, spikes and transients.