MP9840

36V, 3.5A, Low IQ,

Synchronous Step-Down Converter

DESCRIPTION

The MP9840 is a high-frequency, synchronous,

rectified,

step-down,

switch-mode

converter

with built-in power MOSFETs. It offers a very

compact

solution

that

achieves

3.5A

of

continuous output current with excellent load

and line regulation over a wide 3.3V to 36V

input supply range. The switching frequency

can be programmed or synchronized to an

external clock in the range of 350kHz to

2.5MHz. The synchronous operation and ultra-

low

14μA sleep mode quiescent current provide

high efficiency over the output current load

range, allowing the MP9840 to be used in a

variety of step-down applications in automotive

input

environments

and

battery-powered

applications.

Peak-current-mode

operation

provides

fast

transient response and eases loop stabilization.

The excellent low dropout performance allows

the MP9840 to be used in high duty cycle

applications.

Full protection features include over-current

protection (OCP), short-circuit protection (SCP),

and thermal shutdown. An open-drain power

good (PG) signal indicates when the output is

within 10% of its nominal voltage.

The MP9840 is available in a space-saving

QFN-16 (3mmx4mm) package.

FEATURES

• 2

μA Low Shutdown Supply Current

•

14μA No-Load Quiescent Current

• Internal 125

mΩ High-Side and 55mΩ Low-

Side MOSFET

• 350kHz to 2.5MHz Programmable Switching

Frequency

• Power Good (PG) Output

• External Soft Start (SS)

• 80ns Minimum On Time

• Selectable Forced CCM and AAM

• Hiccup Over-Current Protection (OCP)

• Available in a QFN-16 (3mmx4mm)

Package

APPLICATIONS

• Automotive Systems

• Industrial Power Systems

All MPS parts are lead-free, halogen-free, and adhere to the RoHS

directive. For MPS green status, please visit the MPS website under

Quality Assurance. “MPS” and “The Future of Analog IC Technology” are

registered trademarks of Monolithic Power Systems, Inc.

TYPICAL APPLICATION

VOUT

SW

EN

VIN

BST

MP9840

PHASE

SS

FREQ

SYNC

FB

VCC

PG

BIAS

VIN

GND

OFF ON

MP9840 Rev. 1.01

www.MonolithicPower.com

1

1/23/2018

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