LTC4232

13

4232fb

For more information www.linear.com/LTC4232

APPLICATIONS INFORMATION

that connect to the sense resistor and MOSFET. The PCB

pin to balance current in the MOSFET bond wires. Figure 6

shows a recommended layout for the LTC4232.

Although the MOSFET is self protected from overtem-

perature, it is recommended to solder the backside of the

package to a copper trace to provide a good heat sink. Note

that the backside is connected to the SENSE pin and can-

not be soldered to the ground plane. During normal loads

the power dissipated in the MOSFET is as high as 1.9W.

A 10mm × 10mm area of 1oz copper should be sufficient.

This area of copper can be divided in many layers.

It is also important to put C1, the bypass capacitor for

and GND.

4232 F06

HEAT SINK

VIA TO

SINK

GND

C

OUT

Figure 6. Recommended Layout

Figure 7. 12V, 5A Backplane Resident Application with Insertion Activated Turn-On

Additional Applications

TheLTC4232hasawideoperatingrangefrom2.9Vto15V.

The UV, OV and PG thresholds are set with few resistors.

All other functions are independent of supply voltage.

In addition to Hot Swap applications, the LTC4232 also

functions as a backplane resident switch for removable

load cards (see Figure 7.)

Thelastpageshowsa3.3VapplicationwithaUVthreshold

of 2.87V, an OV threshold of 3.77V and a PG threshold

of 3.05V.

R5

150k

R6

20k

C1

1µF

20k

4232 F07

PG

OUT

FB

UV

GND

GATE

LTC4232DHC

OV

TIMER

FLT

12V

5A

12V

R7

10k

R1

226k

R2

20k

12V

R4

20k

R3

140k

LOAD

ADC

Z1

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