A5975AD datasheet(28/50 Pages) STMICROELECTRONICS

Il numero della parte	A5975AD

Spiegazioni elettronici	Voltage feed-forward

PDF	50 Pages

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Produttore elettronici	STMICROELECTRONICS [STMicroelectronics]

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A5975AD

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Doc ID 018761 Rev 1

Switching losses due to turning on and off. These are derived using the following

equation:

Equation 24

where TRISE and TFALL represent the switching times of the power element that cause the

switching losses when driving an inductive load (see Figure 14). TSW is the equivalent

switching time.

Figure 14.

Switching losses

Quiescent current losses.

Equation 25

where IQ is the quiescent current.

Example:

–VIN = 12 V

–VOUT = 3.3 V

–IOUT = 2.5 A

RDS(on) has a typical value of 0.25 @ 25 °C and increases up to a maximum value of 0.5. @

150 °C. We can consider a value of 0.4

Ω.

TSW is approximately 70 ns.

IQ has a typical value of 5 mA @ VIN = 12 V.

OUT

OFF

()

------------------------------------ F

OUT

⋅⋅

⋅

A5975AD Scheda tecnica(PDF) 28 Page - STMicroelectronics