Texas Instruments LMP8481MMX-S/NOPB

Overview

LMP8481MMX-S/NOPB from Texas Instruments is a precision bidirectional high-side current sense amplifier with fixed 60V/V gain, 4.0–76V common-mode input range, ±80µV offset, 270kHz bandwidth, and buffered 5mA output drive-designed for vehicle battery monitoring and telecom power rail sensing.

For engineers reviewing the LMP8481MMX-S/NOPB datasheet, LMP8481MMX-S/NOPB pinout, LMP8481MMX-S/NOPB application, or LMP8481MMX-S/NOPB equivalent, this page delivers verified specifications, VSSOP-8 pin mapping, bidirectional sensing configuration guidance, and validated alternatives for automotive and industrial current measurement systems.

Technical Context

The LMP8481MMX-S/NOPB implements a two-stage architecture: first, a precision thin-film resistor-based voltage-to-current converter referenced to high common-mode voltage; second, a differential amplifier with internal 14V LDO, 5× gain stage, and level-shifting output driven by dual reference inputs (VREFA/VREFB). Its independent supply (4.5–76V) and input common-mode (4.0–76V) ranges enable direct connection to monitored load rails without auxiliary supplies.

Unlike unidirectional LMP8480 variants, the LMP8481MMX-S/NOPB supports true bidirectional sensing via externally configurable reference biasing-allowing zero-current output at GND, VCC/2, or mid-scale ADC reference-while maintaining DC CMRR of 124dB and PSRR of 122dB to reject system noise in harsh environments.

Key Specifications

Pinout & Package

Package: 8-pin VSSOP (3.00mm × 3.00mm), thermally enhanced for high-voltage isolation and PCB space efficiency in compact power modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side current sensing applications.

Compared with MAX4081ASA+, LMP8481MMX-S/NOPB delivers 2.5× lower offset and 16V higher common-mode tolerance; versus INA240A1QDRQ1, it trades ultra-low offset for integrated bidirectional reference flexibility and simpler system-level design.

Availability

LMP8481MMX-S/NOPB is available at Aetrix Electronics and suitable for automotive battery monitoring, telecom rectifier current sensing, and solar inverter DC link monitoring requiring stable component supply and long-term production continuity.

Supply support for LMP8481MMX-S/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision signal conditioning and high-voltage interface ICs.

The LMP8481MMX-S/NOPB belongs to TI's LMP848x precision high-side current sense amplifier family, engineered specifically for accurate bidirectional current measurement in automotive, industrial, and telecom power systems operating up to 76V.

FAQ

What is the maximum common-mode voltage supported by the LMP8481MMX-S/NOPB?

The LMP8481MMX-S/NOPB supports a common-mode input voltage range of 4.0V to 76V. This allows direct connection to high-voltage rails such as 48V telecom systems or 72V electric vehicle battery packs without external level-shifting circuitry. Operation below 4.0V is not guaranteed, and absolute maximum rating is 85V per pin.

How does the LMP8481MMX-S/NOPB achieve bidirectional current sensing?

The LMP8481MMX-S/NOPB achieves bidirectional sensing through its dual reference inputs (VREFA and VREFB), which set the output zero point. When configured with VREFA = VCC and VREFB = GND, the output centers at VCC/2-enabling positive current to produce voltage above mid-scale and negative current below it. This eliminates need for external op-amps or level-shifters in H-bridge or battery charge/discharge monitoring.

Can the LMP8481MMX-S/NOPB operate from the same supply as the monitored load?

Yes-the LMP8481MMX-S/NOPB has independent supply (4.5–76V) and common-mode (4.0–76V) ranges, enabling it to be powered directly from the load rail. For example, a 48V battery system can power the LMP8481MMX-S/NOPB on VCC while measuring current across a shunt on that same 48V rail-reducing bill-of-materials and simplifying PCB layout.

What is the purpose of the NC pins (pins 3, 6, and 7) on the LMP8481MMX-S/NOPB?

Pin 3 is unconnected (NC); pins 6 and 7 are functional VREFB and VREFA inputs-not NC. Pin 3 must remain unconnected per TI's layout guidelines to avoid parasitic coupling or ESD path disruption. Incorrect routing or soldering of pin 3 may degrade CMRR or cause latch-up in high-noise environments.

Does the LMP8481MMX-S/NOPB require external passive components for basic operation?

For basic unidirectional operation, the LMP8481MMX-S/NOPB requires only a 0.1µF bypass capacitor on VCC and proper Kelvin connections to RSP/RSN. For bidirectional operation, external reference sources (e.g., precision voltage divider or ADC reference) must drive VREFA and VREFB. No gain-setting resistors or compensation networks are needed-the 60V/V gain is factory-trimmed and internally fixed.