Can this diode be removed?

灞波儿奔

Can this diode be removed? [Copy link]

D1 is a Schottky diode. What is its function? Can it be removed?

The following is a typical circuit of a step-down synchronous DCDC chip

D1 in the figure is a Schottky diode. What does it do? Check the official manual. The internal circuit of this step-down DCDC is as follows. If this diode is freewheeling, the MOS tube has a body diode. When both tubes are turned off, the freewheeling can be achieved through the body diode.

tagetage

D1 is a Schottky diode. What is its function? Can it be removed? ----- It serves as a freewheeling inductor and cannot be removed.

When both tubes are turned off, can the current be continued through the body diode? - No.

Please design according to the official circuit guidance.

maychang

"D1 is a Schottky diode. What is its function? Can it be removed?"

The function of D1 is to continue the inductor current and it cannot be removed at will.

灞波儿奔

tagetage posted on 2021-12-20 10:30 D1 is a Schottky diode. What is its function? Can it be removed? ----- It serves as the inductor's freewheeling function and cannot be removed. When both tubes are turned off...

Why, with the same output and typical circuit, this circuit does not have this diode?

灞波儿奔

maychang posted on 2021-12-20 10:34 "D1 is a Schottky diode. What is its function? Can it be removed? ?" The function of D1 is to continue the inductor current and cannot be removed at will.

Why, with the same output and typical circuit, this circuit does not have this diode?

tagetage

Please read the data sheet carefully, turn to the back of the data sheet a few pages.

dcexpert

灞波儿奔Published on 2021-12-20 10:41 Then why, with the same output and a typical circuit, this circuit does not have this diode?

Some chips now have a freewheeling diode integrated inside, so this diode is optional and can be used according to the situation.

Gen_X

There is no doubt about the effect, what everyone said is right!

For a step-down circuit with a small input voltage and low power, it can be omitted if efficiency and other factors are not important. However, it cannot be omitted for a step-up circuit.

Because the inductance is small and the current is small, the harm of the inductance is also small.

Fred_1977

This diode is actually an option. It can play a protective role. It can work normally without it. However, a circuit is not a question of whether it can be used or not. If it is to become a product with stable reliability, it must be considered to be more stable.