TPPM0302

400-mA LOW-DROPOUT REGULATOR

WITH AUXILIARY POWER MANAGEMENT AND POK

SLVS316 – NOVEMBER 2000

10

POST OFFICE BOX 655303

APPLICATION INFORMATION

In a multilayer board application, the thermal vias are the primary method of heat transfer from the package

thermal pad to the internal ground plane. The efficiency of this method depends on several factors (die area,

number of thermal vias, thickness of copper) Consult the

PowerPAD Thermally Enhanced Package Technical

Brief.

single-layer PCB

Package Outline

Use as Much Copper Area

as Possible for Heat Spread

Package Thermal Pad

Figure 15. Land Configuration for Single-layer PCB

Layout recommendations for a single-layer PCB utilize as much copper area as possible for power

management.

In a single layer board application, the thermal pad is attached to a heat spreader (copper area) by using low

thermal impedance attachment method (solder paste or thermal conductive epoxy).

In both of the methods mentioned above, it is advisable to use as many copper traces as possible to dissipate

the heat.

IMPORTANT

If the attachment method is NOT implemented correctly, the

functionality of the product is not efficient. Power dissipation

capability will be adversely affected if the device is incorrectly

mounted onto the circuit board.

8

TPPM0302

1

5VAUX

NC

7

2

5VCC

GND

0.1

µF

0.1

µF

4.7

µF

6

3

3.3VOUT

NC

4.7

µF

5

4

3.3VAUX

POK

0.1

µF

4.7

µF

4.7

µF

3.3VOUT

5 k

Ω

Figure 16. Typical Application Schematic