LT1999 - High Voltage, Bidirectional Current Sense Amplifier


  • Buffered Output with 3 Gain Options: 10V/V, 20V/V, 50V/V
  • Gain Accuracy: 0.5% Max
  • Input Common Mode Voltage Range: –5V to 80V
  • AC CMRR > 80dB at 100kHz
  • Input Offset Voltage: 1.5mV Max
  • –3dB Bandwidth: 2MHz
  • Smooth, Continuous Operation Over Entire Common Mode Range
  • 4kV HBM Tolerant and 1kV CDM Tolerant
  • Low Power Shutdown <10μA
  • –55°C to 150°C Operating Temperature Range
  • 8-Lead MSOP and 8-Lead SO (Narrow) Packages
  • 8-Lead MSOP Pinout Option Engineered for FMEA

Typical Application

LT1999 Typical Application
LT1999 Typical Application


The LT®1999 is a high speed precision current sense amplifier, 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 monitoring 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.


For complete and up to date package information and drawings, please refer to our packaging page

MS-8, SO-8

LT1999 Package Drawing
LT1999 Package Drawing
LT1999 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price (1-99) Price (1k)* RoHS Data
LT1999CMS8-10#PBF MSOP 8 C $2.69 $1.92 View
LT1999CMS8-10#TRPBF MSOP 8 C $2.75 $1.98 View
LT1999CMS8-10F#PBF MSOP 8 C $2.69 $1.92 View
LT1999CMS8-10F#TRPBF MSOP 8 C $1.98 View
LT1999CMS8-20#PBF MSOP 8 C $2.69 $1.93 View
LT1999CMS8-20#TRPBF MSOP 8 C $2.75 $1.98 View
LT1999CMS8-20F#PBF MSOP 8 C $2.69 $1.92 View
LT1999CMS8-20F#TRPBF MSOP 8 C $1.98 View
LT1999CMS8-50#PBF MSOP 8 C $2.69 $1.92 View
LT1999CMS8-50#TRPBF MSOP 8 C $2.75 $1.98 View
LT1999CMS8-50F#PBF MSOP 8 C $2.69 $1.92 View
LT1999CMS8-50F#TRPBF MSOP 8 C $1.98 View
LT1999CS8-10#PBF SO 8 C $2.69 $1.92 View
LT1999CS8-10#TRPBF SO 8 C $2.75 $1.98 View
LT1999CS8-20#PBF SO 8 C $2.69 $1.92 View
LT1999CS8-20#TRPBF SO 8 C $2.75 $1.98 View
LT1999CS8-50#PBF SO 8 C $2.69 $1.92 View
LT1999CS8-50#TRPBF SO 8 C $2.75 $1.98 View
LT1999HMS8-10#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-10#TRPBF MSOP 8 H $3.58 $2.57 View
LT1999HMS8-10F#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-10F#TRPBF MSOP 8 H $2.57 View
LT1999HMS8-20#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-20#TRPBF MSOP 8 H $3.58 $2.57 View
LT1999HMS8-20F#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-20F#TRPBF MSOP 8 H $2.57 View
LT1999HMS8-50#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-50#TRPBF MSOP 8 H $3.58 $2.57 View
LT1999HMS8-50F#PBF MSOP 8 H $3.52 $2.51 View
LT1999HMS8-50F#TRPBF MSOP 8 H $2.57 View
LT1999HS8-10#PBF SO 8 H $3.52 $2.51 View
LT1999HS8-10#TRPBF SO 8 H $3.58 $2.57 View
LT1999HS8-20#PBF SO 8 H $3.52 $2.51 View
LT1999HS8-20#TRPBF SO 8 H $3.58 $2.57 View
LT1999HS8-50#PBF SO 8 H $3.52 $2.51 View
LT1999HS8-50#TRPBF SO 8 H $3.58 $2.57 View
LT1999IMS8-10#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-10#TRPBF MSOP 8 I $3.08 $2.21 View
LT1999IMS8-10F#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-10F#TRPBF MSOP 8 I $2.21 View
LT1999IMS8-20#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-20#TRPBF MSOP 8 I $3.08 $2.21 View
LT1999IMS8-20F#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-20F#TRPBF MSOP 8 I $2.21 View
LT1999IMS8-50#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-50#TRPBF MSOP 8 I $3.08 $2.21 View
LT1999IMS8-50F#PBF MSOP 8 I $3.02 $2.15 View
LT1999IMS8-50F#TRPBF MSOP 8 I $2.21 View
LT1999IS8-10#PBF SO 8 I $3.02 $2.15 View
LT1999IS8-10#TRPBF SO 8 I $3.08 $2.21 View
LT1999IS8-20#PBF SO 8 I $3.02 $2.15 View
LT1999IS8-20#TRPBF SO 8 I $3.08 $2.21 View
LT1999IS8-50#PBF SO 8 I $3.02 $2.15 View
LT1999IS8-50#TRPBF SO 8 I $3.08 $2.21 View
LT1999MPMS8-10#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-10#TRPBF MSOP 8 MP $6.89 $4.94 View
LT1999MPMS8-10F#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-10F#TRPBF MSOP 8 MP $4.94 View
LT1999MPMS8-20#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-20#TRPBF MSOP 8 MP $6.89 $4.94 View
LT1999MPMS8-20F#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-20F#TRPBF MSOP 8 MP $4.94 View
LT1999MPMS8-50#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-50#TRPBF MSOP 8 MP $6.89 $4.94 View
LT1999MPMS8-50F#PBF MSOP 8 MP $6.83 $4.88 View
LT1999MPMS8-50F#TRPBF MSOP 8 MP $4.94 View
LT1999MPS8-10#PBF SO 8 MP $6.83 $4.88 View
LT1999MPS8-10#TRPBF SO 8 MP $6.89 $4.94 View
LT1999MPS8-20#PBF SO 8 MP $6.83 $4.88 View
LT1999MPS8-20#TRPBF SO 8 MP $6.89 $4.94 View
LT1999MPS8-50#PBF SO 8 MP $6.83 $4.88 View
LT1999MPS8-50#TRPBF SO 8 MP $6.89 $4.94 View
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1698A-A LT1999-10 (MS8) Demoboard $50.00
DC1698A-B LT1999-20 (MS8) Demoboard $50.00
DC1698A-C LT1999-50 (MS8) Demoboard $50.00
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Click here to view our complete list of demo boards


  • High Side or Low Side Current Sensing
  • H-Bridge Motor Control
  • Solenoid Current Sense
  • High Voltage Data Acquisition
  • PWM Control Loops
  • Fuse/MOSFET Monitoring

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