LMP8278_15 Datasheet, PDF (1/23 Pages) Texas Instruments – LMP8278Q High Common Mode, 14 x Gain, Precision Current Sensing Amplifier

LMP8278
www.ti.com
SNAS575A – FEBRUARY 2012 – REVISED MARCH 2013
LMP8278Q High Common Mode, 14 x Gain, Precision Current Sensing Amplifier
Check for Samples: LMP8278
FEATURES
1
•23 TCVos ±15μV/°C Max
• CMRR 80 dB Min
• Input Offset Voltage ±2 mV max
• CMVR −2V to 40V
• Operating Ambient Temperature Range −40°C
to 125°C
• Single Supply Operation
• Min / Max Limits 100% Tested unless
Otherwise Noted
• LMP8278Q Available in Automotive AEC-Q100
Grade 1 Qualified Version
APPLICATIONS
• High Side and Low Side Driver Configuration
Current Sensing
• Automotive Fuel Injection Control
• Transmission Control
• Power Steering
• Battery Management Systems
DESCRIPTION
The LMP8278 is a fixed 14x gain precision current
sense amplifier. The part amplifies and filters small
differential signals in the presence of high common
mode voltages. The part operates from a single 5V
supply voltage. With an input common mode voltage
range from -2V to +28V the gain is very precise
(±0.5%). The part can handle common mode voltages
in the range -2V to +40V with relaxed specifications.
The LMP8278 is a member of the Linear Monolithic
Precision ( LMP™) family and is ideal for
unidirectional current sensing applications. The
parameter values that are shown in the Electrical
Characteristics table are 100% tested and all bold
values are also 100% tested over temperature,
unless otherwise noted.
The part has a precise gain of 14x which is adequate
in most targeted applications to drive an ADC to its
full scale value. The fixed gain is achieved in two
separate stages, a preamplifier with a gain of 7x and
an output stage buffer amplifier with a gain of 2x. The
connection between the two stages of the signal path
is brought out on two pins to enable the possibility to
create an additional filter network around the output
buffer amplifier. These pins can also be used for
alternative configurations with different gain as
described in Application Information.
The LMP8278Q incorporates enhanced
manufacturing and support processes for the
automotive market, including defect detection
methodologies. Reliability qualification is compliant
with the requirements and temperature grades
defined in the AEC Q100 standard.
Typical Applications
D
I_L
G
Inductive
28V
28V
Load
+5V
S
+5V
load
+5V
+
+
24V
-
-
-
+
D
G
LMP8278
LMP8278
Inductive
Load
LMP8278
S
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
LMP is a trademark of Texas Instruments.
2
All other trademarks are the property of their respective owners.
3
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012–2013, Texas Instruments Incorporated