NCP571, NCV571

http://onsemi.com

8

Figure 20.

GND

Enable

NC

GND

GND

0.1

mF

NL17SZ16

NCP571

0.1

mF

3.3 V

0 V

Enable

2.7 V

2.7 V

0 V

Hints

When the impedance of these lines is high, there is a chance

to pick up noise or cause the regulator to malfunction.

Set external components, especially the output capacitor,

as close as possible to the circuit, and make leads as short as

possible.

Thermal

As power across the NCP571 increases, it might become

necessary to provide some thermal relief. The maximum

power dissipation supported by the device is dependent

upon board design and layout. Mounting pad configuration

on the PCB, the board material, and also the ambient

temperature effect the rate of temperature rise for the part.

This is stating that when the NCP571 has good thermal

conductivity through the PCB, the junction temperature will

be relatively low with high power dissipation applications.

The maximum dissipation the package can handle is given

by:

P

T

If junction temperature is not allowed above the

maximum 125

°C, then the NCP571 can dissipate up to

400 mW @ 25

°C.

The power dissipated by the NCP571 can be calculated

from the following equation:

If a 150 mA output current is needed then the ground

current from the data sheet is 4.0

mA.