LMP8270 Datasheet, PDF (1/17 Pages) National Semiconductor (TI) – High Common Mode, Gain of 20, Precision Voltage Difference Amplifiers

OBSOLETE
LMP8270
www.ti.com
SNOSAK1K – DECEMBER 2004 – REVISED APRIL 2013
High Common Mode, Gain of 20, Precision Voltage Difference Amplifier
Check for Samples: LMP8270
FEATURES
1
•23 Typical Values, T_A = 25°C
• Input Offset Voltage: ±1 mV Max
• TCV_OS: ±15 μV/°C Max
• CMRR: 80 dB Min
• Output Voltage Swing: Rail-to-Rail
• Bandwidth: 80 kHz
• Operating Temperature Range (Ambient):
−40°C to 125°C
• Supply Voltage: 4.75V to 5.5V
• Supply Current: 1 mA
APPLICATIONS
• Fuel Injection Control
• High and Low Side Driver Configuration
Current Sensing
• Power Management Systems
DESCRIPTION
The LMP8270 is a fixed gain differential amplifier with
a −2V to 16V input common mode voltage range and
a supply voltage range of 4.75V to 5.5V. The
LMP8270 is part of the LMP™ precision amplifier
family which will detect, amplify and filter small
differential signals in the presence of high common
mode voltages. The gain is fixed at 20 and is
adequate to drive an ADC to full scale in most cases.
This gain is achieved in two stages, a preamplifier
with a fixed gain of 10 and a second stage amplifier
with a fixed gain of 2. The internal signal path
between these two stages is brought out on two pins,
A1 and A2, which provide a connection for a filter
network.
The LMP8270 will function over an extended common
mode input voltage range making the device suitable
for applications with load dump events such as
automotive systems.
TYPICAL APPLICATION
LMP8270
V_S = 4.75V to 5.5V
+
UP TO
16V _-
INDUCTIVE
LOAD
+IN
R_SENSE
-IN
PROPRIETARY
LEVEL - SHIFT
CIRCUITRY
+
A1
GAIN = 10
-
100 k:
A2
GAIN = 2
OUT
POWER
SWITCH
GND
A1
A2
Figure 1. Low Side Current Sensing
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 © 2004–2013, Texas Instruments Incorporated