Monolithic Power Systems Inc. MCS1802GS-40-Z

Overview

MCS1802GS-40-Z from Monolithic Power Systems is a galvanically isolated, linear Hall-effect current sensor optimized for ±40A bidirectional DC/AC sensing with 33 mV/A sensitivity, ±2.5% total output error over -40°C to +125°C, and 2.2kVRMS isolation voltage-used in motor control inverters for real-time phase current feedback.

For engineers reviewing the MCS1802GS-40-Z datasheet, MCS1802GS-40-Z pinout, MCS1802GS-40-Z application, or MCS1802GS-40-Z equivalent, key selection criteria include primary conductor resistance (0.9 mΩ), adjustable bandwidth (up to 100 kHz via FILT pin), ratiometric 3.3V analog output, and SOIC-8 package compatibility with high-density PCB layouts.

Technical Context

The device integrates a differential Hall array with spinning current offset cancellation to reject stray magnetic fields and achieve stable zero-current output (VCC/2) across temperature. Its internal primary conductor enables direct current path integration without external shunts.

Galvanic isolation is achieved via reinforced insulation between IP+ / IP− leads and signal pins (VCC, VOUT, FILT, GND), supporting basic isolation per IEC 62368-1 with 4.2 mm creepage/clearance. Bandwidth is set either by internal RC filter (100 kHz default) or externally via capacitor on FILT pin.

Key Specifications

Pinout & Package

Package: SOIC-8 (5 mm × 4 mm, 1.27 mm pitch), surface-mount, RoHS-compliant, with reinforced creepage/clearance (4.2 mm) between primary and secondary sides.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear Hall-effect current sensing applications.

Compared with ACS724LLCTR-40AB-T and TLE4971-25S4-10-1-500, MCS1802GS-40-Z uniquely balances 3.3V analog operation, ±2.5% guaranteed accuracy over full temperature, 2.2 kVRMS isolation, and SOIC-8 footprint-making it optimal for space-constrained, thermally demanding industrial inverters.

Availability

MCS1802GS-40-Z is available at Aetrix Electronics and suitable for motor control, automotive onboard chargers, and industrial switch-mode power supplies requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MCS1802GS-40-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, including DC/DC converters, LED drivers, and precision analog sensors.

The MCS1802 series was designed specifically for isolated, high-accuracy current sensing in space-constrained, high-reliability applications such as EV traction inverters and industrial servo drives.

FAQ

What is the maximum continuous primary current the MCS1802GS-40-Z can handle without damage?

The device is rated for ±40A optimized accuracy range, but its primary conductor supports 250A transient current (10 ms) and 3000A surge (8/20 µs) per IEC61000-4-5. Continuous operation beyond ±40A increases nonlinearity and thermal stress; junction temperature must remain ≤165°C. Derating curves are provided in the datasheet's thermal section.

How does the FILT pin affect bandwidth and noise performance?

Connecting a capacitor (CF) between FILT and GND forms a first-order low-pass filter with internal RFi (1.5 kΩ) and CFi (1 nF). A 1 nF CF yields ~100 kHz bandwidth and ~50 mA(RMS) input-referred noise; increasing CF to 10 nF reduces bandwidth to ~10 kHz and noise to ~15 mA(RMS), improving SNR for low-frequency measurements.

Is external calibration required to achieve ±2.5% total output error?

No. The ±2.5% total output error over -40°C to +125°C is factory-trimmed and guaranteed without user calibration. Sensitivity, offset, and ratiometry coefficients (KSENS, KVO) are laser-trimmed during production. System-level calibration is optional for sub-1% applications but not needed for spec-compliant designs.

Can the MCS1802GS-40-Z measure AC current waveforms accurately at 50/60 Hz?

Yes. With FILT unconnected, its 100 kHz bandwidth and 4 µs rising time fully resolve 50/60 Hz sinusoids (periods of 20/16.7 ms) with negligible phase lag (<0.02°). Total harmonic distortion is <0.5% at 60 Hz, and noise density (200 µA/√Hz) ensures >60 dB SNR for 1 A RMS signals.

What is the recommended PCB layout practice for minimizing magnetic coupling errors?

Route high-current traces symmetrically through IP+ and IP− pins with minimal loop area; avoid placing ferromagnetic materials or current-carrying traces within 10 mm of the SOIC-8 body. Use separate ground planes for primary and secondary sides, connected only at a single point near GND pin to prevent ground-loop noise injection into the Hall sensing path.

Does the device support bidirectional current sensing with a single 3.3V supply?

Yes. Zero-current output is VCC/2 = 1.65 V, enabling ±40A measurement with 3.3V supply: +40A produces ~3.0 V, −40A produces ~0.3 V. The output remains linear and ratiometric across the full range, with guaranteed saturation limits of VCC − 0.3 V (high) and 0.3 V (low) at 25°C.

How is galvanic isolation verified in production?

Every unit undergoes 100% production testing per IEC 62368-1 for 2.2 kVRMS withstand isolation voltage at 60 seconds. Dielectric surge strength (6 kV) and creepage/clearance (4.2 mm) are validated during qualification. Certificate of Conformance and test reports are available upon request for automotive and industrial customers.