General Description

The MAX9938 high-side current-sense amplifier offers

500µV (max) and gain error less than 0.5% (max).

Quiescent supply current is an ultra-low 1µA. The

MAX9938 fits in a tiny, 1mm x 1mm UCSP™ package

size or a 5-pin SOT23 package, making the part ideal for

applications in notebook computers, cell phones, PDAs,

and all battery-operated portable devices where accura-

cy, low quiescent current, and small size are critical.

The MAX9938 features an input common-mode voltage

range from 1.6V to 28V. These current-sense amplifiers

have a voltage output and are offered in four gain versions:

25V/V (MAX9938T), 50V/V (MAX9938F), 100V/V

(MAX9938H), and 200V/V (MAX9938W).

The three gain selections offer flexibility in the choice of

the external current-sense resistor. The very low 500µV

(max) input offset voltage allows small 25mV to 50mV

full-current measurement.

The MAX9938 is offered in tiny 4-bump, UCSP (1mm x

1mm x 0.6mm footprint), 5-pin SOT23, and 6-pin µDFN

(2mm x 2mm x 0.8mm) packages specified for operation

over the -40°C to +85°C extended temperature range.

Applications

Cell Phones

PDAs

Power Management Systems

Portable/Battery-Powered Systems

Notebook Computers

Features

o Ultra-Low Supply Current of 1µA (max)

o Low 500µV (max) Input Offset Voltage

o Low < 0.5% (max) Gain Error

o Input Common Mode: +1.6V to +28V

o Voltage Output

o Three Gain Versions Available

25V/V (MAX9938T)

50V/V (MAX9938F)

100V/V (MAX9938H)

200V/V (MAX9938W)

o Tiny 1mm x 1mm x 0.6mm, 4-Bump UCSP,

5-Pin SOT23, or 2mm x 2mm x 0.8mm, 6-Pin

µDFN Packages

1µA, 4-Bump UCSP/SOT23,

Precision Current-Sense Amplifier

________________________________________________________________

Maxim Integrated Products

1

MAX9938T/F/H/W

MAX9938T/F/H/W

54

13

2

RS+

RS-

GND

OUT

GND

SOT23

UCSP

TOP VIEW

(BUMPS ON BOTTOM)

B1

B2

A1

GND

RS+

OUT

RS-

A2

1

2

3

6

5

4

RS-

N.C.

RS+

MAX9938FELT

µDFN

TOP VIEW

(PADS ON BOTTOM)

OUT

N.C.

GND

DRAWINGS NOT TO SCALE

Pin Configurations

19-4110; Rev 3; 10/09

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

EVALUATION

KIT

AVAILABLE

UCSP is a trademark of Maxim Integrated Products, Inc.

Ordering Information

+

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

G45 indicates protective die coating.

Note: All devices are specified over the -40°C to +85°C

extended temperature range.

PART

PIN-

PACKAGE

GAIN

(V/V)

TOP

MARK

MAX9938TEBS+G45

4 UCSP

25

+AGD

MAX9938FEBS+G45

4 UCSP

50

+AGE

MAX9938HEBS+G45

4 UCSP

100

+AGF

MAX9938WEBS+G45

4 UCSP

200

+AGI

MAX9938TEUK+

5 SOT23

25

+AFFB

MAX9938FEUK+

5 SOT23

50

+AFFC

MAX9938HEUK+

5 SOT23

100

+AFFD

MAX9938WEUK+

5 SOT23

200

+AFGZ

MAX9938FELT+

6 µDFN

50

+ACM