Texas Instruments LMP8640HVMKE-H/NOPB

Overview

LMP8640HVMKE-H/NOPB from Texas Instruments is a precision high-voltage current sense amplifier with fixed 100 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 stability are critical.

For engineers reviewing the LMP8640HVMKE-H/NOPB datasheet, LMP8640HVMKE-H/NOPB pinout, LMP8640HVMKE-H/NOPB application, or LMP8640HVMKE-H/NOPB equivalent, key selection criteria include its HV-rated common-mode range (−2 V to +76 V), fixed 100× gain configuration, low offset drift (2.6 µV/°C), buffered output drive capability, and SOT-23-6 thermal performance (R_θJA = 165 °C/W).

Technical Context

This device uses a precision current-sense topology with matched internal R_IN resistors (5 kΩ each) and a feedback resistor network (R_G = 2×R_IN) to achieve fixed 100 V/V gain. Its input stage operates with rail-to-rail common-mode capability down to −2 V, enabling bidirectional current sensing in grounded-load configurations.

The amplifier features a buffered output stage delivering low-impedance drive into 1 MΩ loads, supports supply voltages from 2.7 V to 12 V, and maintains CMRR ≥95 dB across its full −2 V to +76 V common-mode range at 100× gain - critical for rejecting noise in high-noise DC bus environments.

Key Specifications

Pinout & Package

Package: 6-pin Thin SOT-23 (2.9 mm × 1.6 mm), surface-mount, lead-free (NOPB), rated for −40°C to +125°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LMP8640HVMKE-H/NOPB, INA240A1QDGKRQ1 offers automotive qualification and superior PSRR but lacks 100× gain and requires redesign for gain scaling, while MAX40056ATA+T matches gain and common-mode range but increases supply flexibility and bandwidth at the cost of higher power consumption and non-identical pin assignment.

Availability

LMP8640HVMKE-H/NOPB is available at Aetrix Electronics and suitable for industrial power supplies, battery management systems, and motor control applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LMP8640HVMKE-H/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 company specializing in analog and embedded processing technologies, with leadership in precision amplifiers, power management, and signal chain solutions.

The LMP8640HV product line was designed specifically for high-voltage, high-accuracy current sensing in industrial and energy infrastructure applications where extended common-mode range and temperature-stable gain are mandatory.

FAQ

What is the maximum common-mode voltage supported by the LMP8640HVMKE-H/NOPB?

The LMP8640HVMKE-H/NOPB supports a maximum common-mode input voltage of +76 V and a minimum of −2 V relative to V−. This −2 V to +76 V range is validated per TI's SNOSB28G datasheet and enables direct connection to high-voltage DC buses such as 48 V, 60 V, and 72 V battery systems without external attenuation or level shifting. The LMP8640HVMKE-H/NOPB maintains specified performance across this full range.

Does the LMP8640HVMKE-H/NOPB require external gain-setting resistors?

No, the LMP8640HVMKE-H/NOPB does not require external gain-setting resistors. It integrates laser-trimmed internal resistors to deliver a precise fixed gain of 100 V/V. This eliminates component count, layout sensitivity, and temperature drift associated with external resistor networks. The LMP8640HVMKE-H/NOPB achieves ±0.25% max gain error over temperature, as confirmed in TI's electrical characteristics tables.

Can the LMP8640HVMKE-H/NOPB operate from a 3.3 V supply?

Yes, the LMP8640HVMKE-H/NOPB operates from 2.7 V to 12 V supply voltage, fully supporting 3.3 V single-supply operation. At V+ = 3.3 V and V− = 0 V, it delivers valid output swing from 40 mV to 2.65 V (per datasheet Section 7.6), compatible with 3.3 V ADC references. The LMP8640HVMKE-H/NOPB maintains all key specs including CMRR ≥95 dB and gain accuracy within specification at 3.3 V.

What is the function of Pin 5 (NC) on the LMP8640HVMKE-H/NOPB?

Pin 5 of the LMP8640HVMKE-H/NOPB is labeled NC (No Connect) and is internally unconnected. It must remain electrically floating - no trace, pad, or copper pour should contact this pin. TI's datasheet explicitly states "Not Internally Connected" for Pin 5 in the Pin Functions table (Section 6). Connecting or routing to Pin 5 may cause unpredictable behavior or damage; the LMP8640HVMKE-H/NOPB relies on correct NC handling for guaranteed operation.

How does the LMP8640HVMKE-H/NOPB handle bidirectional current sensing?

The LMP8640HVMKE-H/NOPB supports bidirectional current sensing through its −2 V to +76 V common-mode input range and rail-to-rail output capability. When the sense resistor voltage polarity reverses (e.g., regenerative braking), the −IN pin can exceed +IN, producing negative V_SENSE. With V− = 0 V, the LMP8640HVMKE-H/NOPB outputs down to 40 mV (minimum V_OUT), allowing detection of reverse current if referenced to a small positive offset. Full bidirectional operation requires V− biased below ground or use of dual supply - confirmed in TI's Figure 14 (Output vs. V_SENSE zoom near 0 V).