© 2005 Fairchild Semiconductor Corporation

www.fairchildsemi.com

FAN5026 • Rev. 1.0.8

3

Pin Configuration

Figure 3. TSSOP-28

Pin Definitions

Pin #

Name

Description

1

AGND

Analog Ground. This is the signal ground reference for the IC. All voltage levels are measured

with respect to this pin

2

LDRV1

Low-Side Drive. The low-side (lower) MOSFET driver output. Connect to gate of low-side

MOSFET.

27

LDRV2

3

PGND1

Power Ground. The return for the low-side MOSFET driver. Connect to source of low-side

MOSFET.

26

PGND2

4

SW1

Switching Node. Return for the high-side MOSFET driver and a current sense input. Connect

to source of high-side MOSFET and low-side MOSFET drain.

25

SW2

5

HDRV1

High-Side Drive. High-side (upper) MOSFET driver output. Connect to gate of high-side

MOSFET.

24

HDRV2

6

BOOT1

BOOT. Positive supply for the upper MOSFET driver. Connect as shown in Figure 4.

23

BOOT2

7

ISNS1

Current-Sense Input. Monitors the voltage drop across the lower MOSFET or external sense

resistor for current feedback.

22

ISNS2

8

EN1

Enable. Enables operation when pulled to logic HIGH. Toggling EN resets the regulator after a

latched fault condition. These are CMOS inputs whose state is indeterminate if left open.

21

EN2

9

GND

Ground

20

10

VSEN1

Output Voltage Sense. The feedback from the outputs; used for regulation as well as PG,

under-voltage, and over-voltage protection and monitoring.

19

VSEN2

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