LT6100 Datasheet, PDF (1/16 Pages) Linear Technology – Precision, Gain Selectable High Side Current Sense Amplifier

FEATURES
■ _{Input Offset Voltage: 300µV (Max)}
■ _{Sense Inputs Up to 48V}
■ _{0.5% Gain Accuracy}
■ _{Pin Selectable Gain: 10, 12.5, 20, 25, 40, 50V/V}
■ _{Separate Power Supply: 2.7V to 36V}
■ _{Operating Current: 60µA}
■ _{Sense Input Current (VCC Powered Down): 1nA}
■ _{Reverse Battery Protected to – 48V}
■ _{Buffered Output}
■ _{Noise Filtering Input}
■ _{–40°C to 125°C Operating Temperature Range}
■ _{Available in 8-Lead DFN and MSOP Packages}
U
APPLICATIO S
■ _{Battery Monitoring}
■ _{Fuse Monitoring}
■ _{Portable and Cellular Phones}
■ _{Portable Test/Measurement Systems}
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
LT6100
Precision, Gain Selectable
High Side Current Sense
Amplifier
DESCRIPTIO
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 ex-
tends 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 excess
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 APPLICATIO
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
LOAD
V_{EE FIL}
4
3
CONFIGURED FOR GAIN = 25V/V
220pF
6100 TA01a
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
–1.0
–1.5
0
5 10 15 20 25 30 35 40 45 50
V_S SENSE INPUT VOLTAGE (V)
6100 TA01b
6100f
1