LMP8276 Datasheet, PDF (1/16 Pages) Texas Instruments – Bidirectional Precision Voltage Difference Amplifier

OBSOLETE
LMP8276
www.ti.com
SNOSAK2K – DECEMBER 2004 – REVISED APRIL 2013
LMP8276 High Common Mode, Gain of 20, Bidirectional Precision Voltage Difference
Amplifier
Check for Samples: LMP8276
FEATURES
1
•23 Typical Values, T_A = 25°C
• Bidirectional Current Sense Capability
• Input Offset Voltage: ±2 mV Max
• TCVos: ±30 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 LMP8276 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
LMP8276 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 fixed gain is achieved in two separate stages, a
preamplifier with gain of +10 and a second stage
amplifier with a gain of +2. The internal signal path is
brought out on two pins that provide a connection for
a filter network.
The LMP8276 will function over an extended common
mode input voltage range making the device suitable
for applications with load dump events such as
automotive systems.
The mid-rail offset adjustment pin enables the user to
utilize this device for bidirectional current sensing.
This is achieved by adjusting an externally set
voltage reference. Accurate bidirectional load current
measurements are achieved when monitoring the
output with respect to this reference voltage.
TYPICAL APPLICATION
+
UP TO
16V _-
LMP8276
INDUCTIVE
LOAD
+IN
R_SENSE
-IN
PROPRIETARY
LEVEL - SHIFT
CIRCUITRY
V_S = 4.75V to 5.5V
+
A1
GAIN = 10
-
100 k:
OFFSET
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