10

Maxim Integrated

MAX16909

36V, 220kHz to 1MHz Step-Down Converter

with Low Operating Current

Pin Descriptions (continued)

Internal Block Diagram

PIN

NAME

FUNCTION

TSSOP

TQFN

10

8

SUP

Voltage Supply Input. SUP powers up the internal linear regulator. Connect a minimum

4.7FF capacitor to ground.

11, 12

9, 10

LX

Inductor Switching Node. Connect a Schottky diode between LX and GND.

13, 14

11, 12

SUPSW

Internal High-Side Switch-Supply Input. SUPSW provides power to the internal switch.

Connect a 0.1FF decoupling capacitor and a 4.7FF ceramic capacitor to ground.

15

13

EN

SUP Voltage-Compatible Enable Input. Drive EN low to disable the device. Drive EN

high to enable the device.

16

14

I.C.

Internally Connected. Connect to ground for proper operation.

—

—

EP

Exposed Pad. Connect EP to a large-area contiguous copper ground plane for effective

power dissipation. Do not use as the only IC ground connection. EP must be connected

to GND.

MAX16909

FBSW

OUT

COMP

PGOOD

EN

FB

SOFT-

START

SLOPE

COMP

FBOK

EAMP

HSD

AON

LOGIC

CS

REF

HVLDO

SWITCH-

OVER

OSC

PWM

SUP

BIAS

BST

SUPSW

LX

GND

FSYNC FOSC