Designed as a micropower, precision current sense amplifier, the LT6105IMS8#TRPBF is engineered for very wide input common mode range current monitoring applications. Categorized as a high-performance current sense amplifier within Analog Devices' (formerly Linear Technology) precision analog portfolio, this device is available in a compact 8‑lead MSOP surface‑mount package (IMS8 suffix), optimised for automated SMT assembly and space‑constrained PCB layouts[reference:0]. By monitoring the voltage drop across an external sense resistor, the LT6105 enables accurate, bidirectional current measurement in systems ranging from automotive power management to portable test equipment. Its ability to operate as a high-side or low‑side current monitor, combined with an exceptionally wide common mode range, makes it a versatile building block for precision power monitoring architectures[reference:1].
The core advantage of this current sense amplifier lies in its very wide, Over‑the‑Top® input common mode range, which extends from –0.3V to 44V above the negative supply voltage (V–), independent of the device's own supply voltage[reference:2][reference:3]. This unique capability allows the LT6105 to monitor current on a positive supply rail (true high-side sensing), on a negative supply rail, or even continuously track a battery from full charge down to depletion[reference:4]. Unlike most conventional current sense amplifiers that are restricted to either high‑side or low‑side operation, the LT6105 offers complete flexibility-eliminating the need for different devices for different monitoring topologies and significantly simplifying inventory management for multi‑rail systems[reference:5].
At the heart of the LT6105 is a precision input stage with a maximum input offset voltage of 300μV and a gain accuracy of 1% maximum[reference:6][reference:7]. The gain is configured with two external resistors (RIN and ROUT), offering flexibility from 1V/V to 100V/V[reference:8]. A typical slew rate of 2V/μs ensures fast response to unexpected current changes, while the input common mode rejection and power supply rejection both exceed 100dB, providing excellent measurement accuracy in noisy industrial environments[reference:9][reference:10]. The differential inputs can withstand voltages up to ±44V, making the device ideal for monitoring loads connected through a fuse or a MOSFET switch-even during fault conditions such as a short circuit or power supply failure[reference:11][reference:12]. The device draws only 150μA of supply current from an independent power supply ranging from 2.85V to 36V, making it well‑suited for battery‑powered and always‑on applications[reference:13][reference:14].
The LT6105 is equipped with comprehensive protection and power‑down features as standard. When the V+ supply is powered down, the sense inputs are biased off, drawing only 1nA of current and preventing any loading of the monitored circuit-irrespective of the sense voltage present[reference:15][reference:16]. This feature is particularly valuable in automotive and battery‑monitoring applications where the sense circuit must remain completely isolated when the monitoring system is inactive. The device's robust design is further reflected in its absolute maximum ratings: the differential input voltage can withstand ±44V, and the input voltage (with respect to V–) extends down to –9.5V[reference:17]. The operating temperature range covers ‑40°C to 125°C for the industrial grade, ensuring stable performance under harsh environmental conditions[reference:18][reference:19]. The MSOP package variant (IMS8) is rated for ‑40°C to 85°C and carries a Moisture Sensitivity Level‑1 (MSL‑1) certification, supporting unlimited reflow soldering production standards[reference:20].
Key electrical specifications include a gain bandwidth product of 100kHz[reference:21][reference:22], a full‑scale output current of 1mA minimum[reference:23][reference:24], and a typical input bias current of 15μA to 16μA[reference:25][reference:26]. The device offers a common mode rejection ratio (CMRR) of 120dB, delivering outstanding rejection of common‑mode noise[reference:27][reference:28]. The supply voltage range of 2.85V to 36V (or ±1.425V to ±18V for dual‑supply operation) accommodates a wide variety of system power rails[reference:29]. The component complies with RoHS environmental directives and is available in tape‑and‑reel packaging (TR suffix) for high‑volume automated assembly.
Common application scenarios for this precision current sense amplifier include automotive power management, battery monitoring, fuse and MOSFET switch monitoring, power management in portable test and measurement systems, DC‑DC converter current sensing, and load balancing in distributed power architectures[reference:30][reference:31][reference:32]. Typical use cases involve high-side current monitoring in automotive ECUs to detect overcurrent conditions, battery charge/discharge monitoring in portable devices, and precision load current measurement in industrial control systems. The LT6105 is also well‑suited for monitoring currents in quarter‑, half‑, and full‑bridge inductive load driving applications, thanks to its wide input common mode range[reference:33]. Its ability to continuously monitor a battery from full charge to depletion, combined with the Over‑the‑Top® input range, makes it an excellent choice for battery management systems in electric vehicles and energy storage applications[reference:34]. Thanks to its flexible high-side or low‑side sensing topology, precision 300μV offset, 100dB+ CMRR, and robust ±44V differential input protection, the LT6105IMS8#TRPBF has become a trusted choice for engineers seeking a versatile, accurate, and reliable current sense amplifier-one that delivers the measurement precision of a dedicated monitor with the flexibility to adapt to virtually any system voltage domain, all while maintaining the simplicity and compact footprint of an 8‑pin MSOP IC[reference:35].
