19-4110; Rev 3; 10/09
1µA, 4-Bump UCSP/SOT23,
Precision Current-Sense Amplifier
MAX938
General Description
Features
The MAX9938 high-side current-sense amplifier offers
o Ultra-Low Supply Current of 1µA (max)
precision accuracy specifications of V
less than
OS
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
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.
o Three Gain Versions Available
25V/V (MAX9938T)
50V/V (MAX9938F)
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).
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
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
voltage for very low voltage drop at
full-current measurement.
Ordering Information
PIN-
PACKAGE
GAIN
(V/V)
TOP
MARK
full-scale V
SENSE
PART
MAX9938TEBS+G45
MAX9938FEBS+G45
MAX9938HEBS+G45
MAX9938WEBS+G45
MAX9938TEUK+
4 UCSP
4 UCSP
4 UCSP
4 UCSP
5 SOT23
5 SOT23
5 SOT23
5 SOT23
6 µDFN
25
50
+AGD
+AGE
+AGF
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.
100
200
25
+AGI
+AFFB
+AFFC
+AFFD
+AFGZ
+ACM
Applications
MAX9938FEUK+
50
Cell Phones
MAX9938HEUK+
MAX9938WEUK+
MAX9938FELT+
100
200
50
PDAs
Power Management Systems
Portable/Battery-Powered Systems
Notebook Computers
+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.
UCSP is a trademark of Maxim Integrated Products, Inc.
Pin Configurations
TOP VIEW
(BUMPS ON BOTTOM)
TOP VIEW
(PADS ON BOTTOM)
RS+
5
RS-
4
RS+
A1
A2
RS-
RS-
6
1
OUT
N.C.
GND
MAX9938T/F/H/W
MAX9938T/F/H/W
5
4
N.C.
RS+
2
3
MAX9938FELT
GND
B1
B2
OUT
1
2
3
UCSP
GND
GND
OUT
µDFN
SOT23
DRAWINGS NOT TO SCALE
________________________________________________________________ Maxim Integrated Products
1
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.