Pin Description (continued)

PIN

NAME

FUNCTION

2

EN

High-Voltage-Compatible Enable Input. If this pin is low, the part is off.

3

BST

Bootstrap Pin for HS Driver. It is recommended to use 0.1μF from BST to LX.

4

SUP

Supply Input. Connect a 4.7μF ceramic capacitor from SUP to PGND.

5

LX

Buck Switching Node. Connect inductor between LX and OUT. See the Inductor Selection section.

If the part is off, this node is high impedance.

6

PGND

Power Ground. Ground return path for all high-current/high-frequency noisy signals.

7

AGND

Analog Ground. Ground return path for all ‘quiet’ signals.

8

FB

Connect this pin to BIAS for fixed output voltage options. For MAX25232ATCF and

MAX25232ATCG, use it as a FB pin to set the output voltage.

9

OUT

Buck Regulator Output-Voltage-Sense Input. Bypass OUT to PGND with ceramic capacitors.

10

BIAS

5V Internal Bias Supply. Connect a 1μF (min) ceramic capacitor to AGND.

11

SYNC

Sync Input. If connected to ground or open, skip-mode operation is enabled under light loads; if

connected to BIAS, forced-PWM mode is enabled. This pin has a 1MΩ internal pulldown.

12

PGOOD

Open-Drain Reset Output. External pullup required.

-

EP

Exposed Pad. EP must be connected to ground plane on PCB, but is not a current-carrying path

and is only needed for thermal transfer.

MAX25232

www.maximintegrated.com

Maxim Integrated | 9