Texas Instruments LMP8640HVMKX-F/NOPB

Overview

LMP8640HVMKX-F/NOPB from Texas Instruments is a precision high-voltage current sense amplifier with fixed 50 V/V gain, -2 V to +76 V common-mode input range, 0.25% max gain error, 900 µV input offset voltage, and 6-pin SOT-23 package. It enables accurate high-side current monitoring in industrial power supplies and battery management systems where wide common-mode voltage and temperature-stable gain are critical.

For engineers reviewing the LMP8640HVMKX-F/NOPB datasheet, LMP8640HVMKX-F/NOPB pinout, LMP8640HVMKX-F/NOPB application, or LMP8640HVMKX-F/NOPB equivalent, this device supports high-accuracy DC/AC current sensing in 12 V–48 V DC systems, delivers buffered low-impedance output for direct ADC interfacing, and maintains <0.51% gain error over -40°C to +125°C.

Technical Context

The LMP8640HVMKX-F/NOPB implements a precision current-sense topology using matched internal resistors (RIN = 5 kΩ) and a high-CMRR error amplifier to reject common-mode transients up to 76 V. Its fixed-gain architecture eliminates external resistor matching errors and ensures stable 50 V/V transfer function across supply voltages from 2.7 V to 12 V.

It features a buffered rail-to-rail output stage capable of sourcing/sinking ≥1 mA, operates with 450 kHz bandwidth at 50 V/V gain, and achieves 103 dB CMRR at 2.1 V–42 V common-mode range-critical for rejecting noise in motor drive and solar inverter current loops.

Key Specifications

Pinout & Package

Package: 6-pin Thin SOT-23 (2.9 mm × 1.6 mm), surface-mount, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage current sense applications.

Compared with INA240A1QDGKRQ1 and MAX40056ASA+T, the LMP8640HVMKX-F/NOPB offers superior bandwidth (450 kHz vs. 120/400 kHz) and wider common-mode range (+76 V vs. +80/+65 V), making it optimal for industrial 48 V–72 V systems requiring fast overcurrent response and robustness against bus transients.

Availability

LMP8640HVMKX-F/NOPB is available at Aetrix Electronics and suitable for industrial power supplies, solar inverters, and 48 V battery management systems requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant manufacturing.

Supply support for LMP8640HVMKX-F/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 amplifiers and high-reliability signal conditioning ICs.

The LMP8640 family was designed specifically for high-accuracy, high-common-mode current sensing in industrial and energy infrastructure applications-emphasizing gain stability, low drift, and robust EMC performance over wide temperature ranges.

FAQ

What is the maximum common-mode voltage supported by the LMP8640HVMKX-F/NOPB?

The LMP8640HVMKX-F/NOPB supports a maximum common-mode input voltage of +76 V and a minimum of -2 V. This extended range allows direct high-side sensing in 48 V and 60 V DC systems, including applications with transient overvoltage events. The specification is validated per TI's SNOSB28G datasheet Section 7.1 Absolute Maximum Ratings and applies across the full -40°C to +125°C operating temperature range for the LMP8640HVMKX-F/NOPB.

Does the LMP8640HVMKX-F/NOPB require external gain-setting resistors?

No, the LMP8640HVMKX-F/NOPB uses internal laser-trimmed resistors to implement its fixed 50 V/V gain. No external resistors are required or recommended-adding external components would degrade accuracy and violate the specified gain error of ±0.25%. The device is optimized for plug-and-play integration with minimal external components, as confirmed in the Functional Block Diagram and Feature Description sections of the official datasheet.

What is the typical supply current of the LMP8640HVMKX-F/NOPB at 5 V supply and 2.1 V common-mode voltage?

The typical supply current of the LMP8640HVMKX-F/NOPB is 722 µA under those conditions, as specified in Table 7.7 Electrical Characteristics 5 V (page 6 of SNOSB28G). This value is measured at TA = 25°C with V+ = 5 V, V− = 0 V, and VCM = 2.1 V. At -40°C to +125°C, supply current ranges from 500 µA to 1250 µA depending on VCM, ensuring low-power operation in thermally constrained designs.

Can the LMP8640HVMKX-F/NOPB drive a 10 nF capacitive load?

No-the LMP8640HVMKX-F/NOPB specifies a maximum output capacitive load of 30 pF (Section 7.6, 7.7, and 7.8 Electrical Characteristics). Driving 10 nF (10,000 pF) would cause severe instability, oscillation, and degraded step response. For larger loads, an external buffer amplifier or RC isolation network is required. This limit is design-critical and verified in TI's characterization data (Figure 12, Figure 16–18).

Is the NC pin on the LMP8640HVMKX-F/NOPB required to be grounded or left floating?

The NC (pin 5) on the LMP8640HVMKX-F/NOPB is Not Internally Connected and must be left floating-no PCB trace, solder, or pull-up/down resistor should be attached. Per the Pin Configuration and Functions table (Section 6, page 3 of SNOSB28G), connecting this pin risks parasitic coupling or latch-up. TI explicitly states "Not Internally Connected" in the datasheet; grounding or biasing it violates the validated layout and thermal performance specifications.