Monolithic Power Systems Inc. MCS1806GS-5-50-Z

Overview

MCS1806GS-5-50-Z from Monolithic Power Systems is a galvanically isolated linear Hall-effect current sensor with ±50A bidirectional sensing range, 5V single-supply operation, and ±2.5% total output error over -40°C to +125°C. It features 3kVRMS isolation, 500VRMS working voltage, 0.9mΩ internal conductor resistance, and ratiometric analog output proportional to AC/DC primary current - deployed in motor control feedback loops and inverter phase-leg monitoring.

For engineers reviewing the MCS1806GS-5-50-Z datasheet, MCS1806GS-5-50-Z pinout, MCS1806GS-5-50-Z application, or MCS1806GS-5-50-Z equivalent, key selection criteria include isolation rating compliance (IEC62368-1), primary conductor thermal derating at ±50A, FILT-pin bandwidth tuning via external capacitor, and zero-current output stability (VOUT(Q) = VCC/2 ±10mV).

Technical Context

The device implements differential Hall sensing with two integrated transducers (PMCF1 = 0.6 mT/A, PMCF2 = 0.3 mT/A) to reject stray magnetic fields, combined with spinning current offset cancellation for stable DC accuracy. Its functional block includes dynamic offset cancellation, POR-regulated power supply, and temperature-compensated sensitivity control.

Isolation is achieved via reinforced dielectric barrier between primary conductor pins (IP+, IP−) and signal pins (VCC, VOUT, FILT, GND), rated for 3kVRMS withstand and 500VRMS continuous working voltage per IEC62368-1. Bandwidth is adjustable up to 100kHz using an external capacitor on FILT, leveraging internal RFI = 1.5kΩ and CFI = 1nF.

Key Specifications

Pinout & Package

SOIC-8 package (5mm × 4mm, 1.57mm height) with creepage/clearance ≥4.2mm for reinforced isolation. Primary current path uses dual parallel pins (IP+, IP−) for low-inductance, high-current conduction; signal side contains standard analog interface pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar isolated current sensing applications.

Compared with ACS724LLCTR-50AB-T and TMC1100A1XATMA1, MCS1806GS-5-50-Z uniquely combines adjustable bandwidth, lower conductor resistance (0.9mΩ vs. ≥1.2mΩ), and tighter total error (±2.5% vs. ±3.0%) in the same SOIC-8 form factor - optimizing space-constrained, thermally sensitive inverter designs.

Availability

MCS1806GS-5-50-Z is available at Aetrix Electronics and suitable for motor controls, multi-phase inverters, and over-current fault protection requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MCS1806GS-5-50-Z 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance power management ICs, with design focus on efficiency, integration, and reliability for industrial, automotive, and computing applications.

The MCS1806 product line delivers isolated current sensing solutions optimized for space-constrained, high-reliability power conversion systems - emphasizing low-loss conduction, magnetic immunity, and seamless integration into existing 5V analog signal chains.

FAQ

What is the maximum continuous primary current the MCS1806GS-5-50-Z can handle without exceeding junction temperature limits?

The device supports ±50A continuous primary current under specified thermal conditions: PCB copper area ≥400mm² (2oz), ambient temperature ≤85°C, and no forced airflow. Self-heating data shows ~45°C rise above ambient at ±50A DC on evaluation board; full derating required above 100°C ambient or with reduced copper.

How does the FILT pin affect noise performance and bandwidth trade-offs?

Connecting a capacitor (CF) between FILT and GND sets the 3dB bandwidth per fBW = 1/(2π × 1.5kΩ × (1nF + CF)). Larger CF lowers bandwidth and input-referred noise (e.g., 10nF yields ~10kHz BW and ~15mA RMS noise); omitting CF enables 100kHz operation with 50mA RMS noise at 60kHz bandwidth.

Can MCS1806GS-5-50-Z measure true RMS AC current directly?

No - it outputs a DC-coupled analog voltage proportional to instantaneous primary current (AC or DC). True RMS calculation requires external signal processing (e.g., µC with RMS firmware or dedicated RMS-to-DC converter) operating on the VOUT waveform.

What is the recommended PCB layout practice for maintaining isolation integrity?

Maintain ≥4.2mm clearance/creepage between IP+ / IP− pads and all signal-side copper (VCC, VOUT, FILT, GND). Use slot-cut isolation barriers in the PCB layer stack; avoid vias or traces crossing the isolation gap; place 1µF bypass capacitor within 2mm of VCC pin with direct GND plane connection.

Does the ±2.5% total output error include lifetime drift effects?

Yes - the ±2.5% specification covers initial error plus lifetime drift contributions: ±1% sensitivity error drift and ±1% total output error drift over 10 years, as validated per JEDEC JESD22-A108F high-temperature operating life testing at 125°C junction temperature.

Is the MCS1806GS-5-50-Z compliant with reinforced insulation standards for medical or industrial safety?

Yes - it is certified to IEC62368-1 for reinforced insulation with 3000VRMS withstand voltage and 500VRMS working voltage, meeting requirements for basic insulation in industrial equipment and supplementary insulation in medical devices per IEC60601-1 Annex D.