Monolithic Power Systems Inc. MCS1802GS-05-P

Overview

MCS1802GS-05-P from Monolithic Power Systems is a galvanically isolated, linear Hall-effect current sensor optimized for ±5A bidirectional DC/AC sensing with 264 mV/A sensitivity, ±2.5% total output error over -40°C to +125°C, and 2.2kVRMS isolation voltage-used in motor control feedback loops where compact size and magnetic immunity are critical.

For engineers reviewing the MCS1802GS-05-P datasheet, MCS1802GS-05-P pinout, MCS1802GS-05-P application, or MCS1802GS-05-P equivalent, key selection criteria include primary conductor resistance (0.9 mΩ), ratiometric 3.3V analog output, adjustable bandwidth up to 100 kHz via FILT pin, and SOIC-8 footprint compatibility with space-constrained 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 (VOUT, FILT, GND, VCC), supporting basic isolation per IEC 62368-1 at 2.2kVRMS withstand voltage and 350 VPK working voltage. Bandwidth is set either by internal RC filter (100 kHz default) or externally via capacitor on FILT pin.

Key Specifications

Pinout & Package

SOIC-8 package (5 mm × 4 mm, 1.27 mm pitch) with reinforced creepage/clearance (4.2 mm) for reinforced isolation compliance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ACS712ELCTR-05B-T, MCS1802GS-05-P delivers tighter accuracy (±2.5% vs ±5%), lower conductor loss (0.9 mΩ vs 1.2 mΩ), and bandwidth flexibility; versus TLE4971-5U, it offers simpler analog interfacing and faster response but no digital diagnostics or higher isolation rating.

Availability

MCS1802GS-05-P is available at Aetrix Electronics and suitable for motor control feedback, automotive battery monitoring, SMPS over-current protection, and industrial load management requiring stable component supply and guaranteed long-term availability.

Supply support for MCS1802GS-05-P 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 is designed for isolated current sensing in compact, high-reliability power systems-targeting applications where galvanic isolation, low thermal drift, and minimal external components are essential.

FAQ

What is the maximum continuous primary current the MCS1802GS-05-P can handle without damage?

The device is rated for ±5A optimized accuracy range, but its primary conductor supports continuous currents up to ±50A (per datasheet surge rating). At ±50A, junction temperature must remain ≤165°C; derating is required above 85°C ambient. The 0.9 mΩ resistance yields only 2.25 W dissipation at 50A, enabling robust thermal performance with minimal heatsinking.

How does the FILT pin affect noise and bandwidth in practical layout?

Connecting a 1 nF capacitor between FILT and GND reduces bandwidth to ~60 kHz and cuts input-referred noise from 200 µA/√Hz to ~50 mA(RMS) (60 kHz BW). Layout best practice: place capacitor <2 mm from FILT/GND pins with short, wide traces to avoid parasitic inductance that could destabilize the internal filter.

Can MCS1802GS-05-P replace a shunt resistor + op-amp + isolator combination?

Yes-its 2.2kVRMS isolation, 0.9 mΩ conductor, and ratiometric 3.3V output eliminate the need for external isolation components. Unlike shunt-based solutions, it avoids common-mode voltage limitations and provides inherent magnetic immunity, reducing layout complexity and improving reliability in noisy environments.

What is the significance of the ±2.5% total output error specification?

This figure combines sensitivity error, offset drift, nonlinearity, and lifetime drift across -40°C to +125°C. It means that at ±5A, output deviation from ideal (VCC/2 ± 1.32 V) remains within ±33 mV-enabling accurate current measurement without system-level calibration in most industrial and automotive applications.

Does the SOIC-8 package meet IPC Class 2 creepage requirements for 300V AC mains applications?

Yes-the 4.2 mm external creepage and clearance distance exceeds IPC-2221B Class 2 minimum (3.2 mm) for 300V AC working voltage. Combined with 2.2kVRMS dielectric strength and IEC 62368-1 certification, it supports reinforced isolation in AC/DC power supplies and industrial inverters.

How does the differential Hall architecture improve accuracy versus single-point Hall sensors?

By measuring magnetic field difference between two spatially separated Hall plates, the MCS1802 cancels uniform external fields (e.g., from adjacent busbars) and suppresses thermal gradient effects. This achieves ±1% Hall plate matching and eliminates magnetic hysteresis-critical for repeatable measurements in dynamic load conditions.

Is the VOUT output compatible with standard 12-bit ADCs without signal conditioning?

Yes-VOUT swings ratiometrically from ~0.3 V to VCC – 0.3 V (2.97 V max at 3.3V), delivering 2.67 V full-scale span. With 264 mV/A sensitivity, ±5A maps to 1.32 V centered at 1.65 V, yielding 324 LSB per amp on a 3.3V-referenced 12-bit ADC-well within optimal resolution range.