LT1999-50_15 Datasheet, PDF (1/26 Pages) Linear Technology – High Voltage, Bidirectional Current Sense Amplifier

LT1999-10/LT1999-20/
LT1999-50
High Voltage, Bidirectional
Current Sense Amplifier
Features
nn _{Buffered Output with 3 Gain Options:}
10V/V, 20V/V, 50V/V
nn _{Gain Accuracy: 0.5% Max}
nn _{Input Common Mode Voltage Range: –5V to 80V}
nn _{AC CMRR > 80dB at 100kHz}
nn _{Input Offset Voltage: 1.5mV Max}
nn _{–3dB Bandwidth: 2MHz}
nn _{Smooth, Continuous Operation Over Entire Common}
Mode Range
nn _{4kV HBM Tolerant and 1kV CDM Tolerant}
nn _{Low Power Shutdown <10µA}
nn _{–55°C to 150°C Operating Temperature Range}
nn _{8-Lead MSOP and 8-Lead SO (Narrow) Packages}
nn _{8-Lead MSOP Pinout Option Engineered for FMEA}
Applications
nn _{High Side or Low Side Current Sensing}
nn _{H-Bridge Motor Control}
nn _{Solenoid Current Sense}
nn _{High Voltage Data Acquisition}
nn _{PWM Control Loops}
nn _{Fuse/MOSFET Monitoring}
Description
The LT^®1999 is a high speed precision current sense am-
plifier, designed to monitor bidirectional currents over a
wide common mode range. The LT1999 is offered in three
gain options: 10V/V, 20V/V, and 50V/V.
The LT1999 senses current via an external resistive shunt
and generates an output voltage, indicating both magnitude
and direction of the sensed current. The output voltage is
referenced halfway between the supply voltage and ground,
or an external voltage can be used to set the reference
level. With a 2MHz bandwidth and a common mode input
range of –5V to 80V, the LT1999 is suitable for monitor-
ing currents in H-Bridge motor controls, switching power
supplies, solenoid currents, and battery charge currents
from full charge to depletion.
The LT1999 operates from an independent 5V supply
and draws 1.55mA. A shutdown mode is provided for
minimizing power consumption.
The LT1999 is available in an 8-lead SOP, an 8-lead MSOP
(original pinout), or an 8-lead pinout option engineered
for FMEA.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Typical Application
V_S
R_S
5V
V⁺
1
V_{+IN 2}
4k
V⁺
V_–IN
3 ^4k
LT1999
SHDN
+
–
0.8k
0.8k
5V
V⁺
4
0.1µF
V⁺
2µA
R_G
8 _VSHDN
–
+
V⁺
7 _VOUT
160k
6 ^VREF
160k
5
0.1µF
1999 TA01a
For more information www.linear.com/LT1999
Full Bridge Armature Current Monitor
V_OUT
2.5V
V_+IN
TIME (10µs/DIV)
1999 TA01b
1999fd
1