LT6100_15 Datasheet, PDF (1/18 Pages) Linear Technology – Precision, Gain Selectable High Side Current Sense Amplifier

FEATURES
n _{Input Offset Voltage: 300µV (Max)}
n _{Sense Inputs Up to 48V}
n _{0.5% Gain Accuracy}
n _{Pin Selectable Gain: 10, 12.5, 20, 25, 40, 50V/V}
n _{Separate Power Supply: 2.7V to 36V}
n _{Operating Current: 60µA}
n _{Sense Input Current (VCC Powered Down): 1nA}
n _{Reverse Battery Protected to –48V}
n _{Buffered Output}
n _{Noise Filtering Input}
n _{–40°C to 125°C Operating Temperature Range}
n _{Available in 8-Lead DFN and MSOP Packages}
APPLICATIONS
n _{Battery Monitoring}
n _{Fuse Monitoring}
n _{Portable and Cellular Phones}
n _{Portable Test/Measurement Systems}
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trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
LT6100
Precision, Gain Selectable
High Side Current Sense
Amplifier
DESCRIPTION
The LT^®6100 is a complete micropower, precision, high
side current sense amplifier. The LT6100 monitors unidi-
rectional currents via the voltage across an external sense
resistor. Fixed gains of 10, 12.5, 20, 25, 40, 50V/V are
obtained by simply strapping or floating two gain select
pins. Gain accuracy is better than 0.5% for all gains.
The LT6100 sense inputs have a voltage range that extends
from 4.1V to 48V, and can withstand a differential voltage
of the full supply. This makes it possible to monitor the
voltage across a MOSFET switch or a fuse. The part can
also withstand a reverse battery condition on the inputs.
Input offset is a low 300µV. CMRR and PSRR are in ex-
cess of 105dB, resulting in a wide dynamic range. A filter
pin is provided to easily implement signal filtering with a
single capacitor.
The LT6100 has a separate supply input, which operates
from 2.7V to 36V and draws only 60µA. When V_CC is
powered down, the sense pins are biased off. This pre-
vents loading of the monitored circuit, irrespective of the
sense voltage. The LT6100 is available in an 8-lead DFN
and MSOP package.
TYPICAL APPLICATION
0A to 33A High Side Current Monitor with 12kHz Frequency Rolloff
4.4V TO 48V
SUPPLY
3V
2
LT6100 ^VCC
8 ^VS+
R_SENSE
3mΩ
1 ^VS–
7
6
A4
A2
V_{OUT 5}
V_OUT = 2.5V
I_SENSE = 33A
Input Offset Voltage
vs V_S Sense Input Voltage
1.5
V_SENSE = 100mV
V_CC = 3V
1.0 T_A = 25°C
0.5
0
–0.5
LOAD
V_{EE FIL}
4
3
CONFIGURED FOR GAIN = 25V/V
220pF
6100 TA01a
–1.0
–1.5
0
5 10 15 20 25 30 35 40 45 50
V_S SENSE INPUT VOLTAGE (V)
6100 TA01b
For more information www.linear.com/LT6100
6100fd
1