19-4233; Rev 0; 8/08
Automotive Current-Sense Amplifier
with Reverse-Battery Protection
General Description
The MAX9937 is a tiny automotive grade current-sense
amplifier designed for unidirectional high-side current-
sense applications. This device addresses major areas
of concern for automotive applications including load-
dump protection up to +40V, reverse-battery protec-
tion, and filtering for EMI and transient performance.
The MAX9937 also features a low input offset voltage of
±1.2mV (max) at +25°C with a low temperature drift of
just 1µV/°C (typ).
The MAX9937 is available in a 5-pin SC70 package and
is rated over the -40°C to +125°C temperature range.
Features
♦ Reverse Battery and Load-Dump Protection
-20V to +40V
♦ +4V to +28V Input Common-Mode Range
♦ Flexible EMI Filtering
♦ Low VOS: ±1.2mV (max)
♦ Low VOS Drift: 1µV/°C (typ)
♦ 20µA Supply Current
♦ 350kHz, 3dB Small Signal Bandwidth
Applications
Automotive Battery Current Sense
Fuse Box Current Sense
ECU Current Monitor
Pin Configuration appears at end of data sheet.
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
MAX9937AXK+T -40°C to +125°C 5 SC70
+Denotes a lead-free/RoHS-compliant package.
T = Tape and reel.
TOP
MARK
+ATB
Typical Application Circuit
RS+
RSENSE
RS-
VBAT = 4V
TO 28V
RRSP
499Ω
RSP
GND
RRSN
499Ω
RSN
VCC
LOAD
5V
BIAS
BLOCK
MICROCONTROLLER
MAX9937
OUT
GAIN = VOUT = ROUT
ADC
VSENSE RRSP
ROUT
10kΩ
________________________________________________________________ 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.