General Description

The MAX5090A/B/C easy-to-use, high-efficiency, high-

voltage step-down DC-DC converters operate from an input

voltage up to 76V, and consume only 310µA quiescent

current at no load. This pulse-width-modulated (PWM)

converter operates at a fixed 127kHz switching frequency at

heavy loads, and automatically switches to pulse-skipping

mode to provide low quiescent current and high efficiency

at light loads. The MAX5090 includes internal frequency

compensation simplifying circuit implementation. The

device can also be synchronized with external system clock

frequency in a noise-sensitive application. The MAX5090

uses an internal low on-resistance and a high-voltage DMOS

transistor to obtain high efficiency and reduce overall system

cost. This device includes undervoltage lockout, cycle-

by-cycle current limit, hiccup-mode output short-circuit

protection, and overtemperature shutdown.

The MAX5090 delivers up to 2A output current. External

shutdown is included, featuring 19µA (typ) shutdown

current. The MAX5090A/MAX5090B versions have fixed

output voltages of 3.3V and 5V, respectively, while the

MAX5090C features an adjustable 1.265V to 11V output

voltage.

The MAX5090 is available in a space-saving 16-pin

thin QFN package (5mm x 5mm) and operates over the

automotive temperature range (-40°C to +125°C).

Applications

● Industrial

● Distributed Power

Features

● Wide Input Voltage Range: 6.5V to 76V

● Fixed (3.3V, 5V) and Adjustable (1.265V to 11V)

Output-Voltage Versions

● 2A Output Current

● Efficiency Up to 92%

● Internal 0.26Ω High-Side DMOS FET

● 310µA Quiescent Current at No Load

● 19µA Shutdown Current

● Internal Frequency Compensation

● Fixed 127kHz Switching Frequency

● External Frequency Synchronization

● Thermal Shutdown and Short-Circuit Current Limit

● -40°C to +125°C Automotive Temperature Range

● 6-Pin (5mm x 5mm) Thin QFN Package

● Capable of Dissipating 2.67W at +70°C

Ordering Information continued at end of data sheet.

19-3872; Rev 1; 9/14

+Denotes a lead(Pb)-free/RoHS-compliant package.

*EP = Exposed pad.

PART

TEMP

RANGE

PIN-

PACKAGE

OUTPUT

VOLTAGE

(V)

MAX5090AATE+ -40°C to +125°C 16 TQFN-EP*

3.3

MAX5090AATE -40°C to +125°C 16 TQFN-EP*

3.3

MAX5090BATE+ -40°C to +125°C 16 TQFN-EP*

5.0

MAX5090BATE -40°C to +125°C 16 TQFN-EP*

5.0

PGND

BST

LX

SGND

FB

5V/2A

VD

100µH

0.22µF

3.3µF

ON/OFF

100µF

SS

SYNC

D1

PDS5100H

DRAIN

0.047µF

68µF

0.47µF

10Ω

VIN

7.5V TO 76V

MAX5090B

15

16

14

13

6

5

7

8

1

2

DRAIN

4

12

EP

11

9

N.C.

N.C.

FB

SS

SYNC

VD

MA5090

3

10

DRAIN

TQFN

TOP VIEW

MAX5090A/B/C

2A, 76V, High-Efficiency MAXPower

Step-Down DC-DC Converters

Typical Operating Circuit

Pin Configuration

Ordering Information

EVALUATION KIT AVAILABLE