Technical Analysis of MLX91205KDC-AAH-003-RE/TU

1. One-sentence Description

MLX91205KDC-AAH-003-RE/TU is an IMC-Hall® current sensor based on Triaxis® technology, enabling high-precision DC to 100kHz wide-band current detection through contact measurement, with a linear voltage signal output.

2. Core Features

• Wide frequency band measurement: supports DC to 100kHz current signals
• High sensitivity: typical value 100 mV/mT (version -AAH-003)
• Low noise: <125 nT/√Hz (10Hz–10kHz)
• Fast response: ultra-short delay of 8μs
• Temperature stability: sensitivity temperature drift <±200 ppm/°C, offset voltage ±50mV (-40°C–125°C)
• Isolation design: non-contact measurement, voltage-withstand isolation
• Package: SOIC-8 surface mount (RE: tape and reel / TU: tube)

3. Core Technical Indicators

4. The Story Behind the Chip

MLX91205 breaks through the limitations of traditional Hall sensors. Through IMC (Integrated Magnetic Concentrator) technology, a ferromagnetic layer is added after the standard CMOS process, amplifying and focusing the magnetic field parallel to the chip surface on the Hall element. This innovation increases sensitivity by more than 10 times, while achieving low noise and low temperature drift (see Chapter 9 of the document for details).

5. Design Concept

• Magnetic field planar detection: traditional Hall sensors are only vertically sensitive, while Triaxis® technology bends magnetic field lines through the IMC layer to achieve efficient measurement of parallel magnetic fields (Chapters 3 and 9 of the document).
• Dynamic offset cancellation: on-chip chopper amplifier eliminates the influence of temperature drift and mechanical stress, with offset voltage as low as ±50mV over the entire temperature range.
• Proportional output: output voltage is proportional to the supply voltage (VDD), reducing the impact of power supply fluctuations.

6. Application Scenarios

7. Unique Advantages

The only Hall current sensor supporting parallel magnetic field measurement. Traditional Hall elements rely on vertical magnetic fields, while MLX91205 converts the parallel magnetic field generated by conductor current into vertical components through the IMC layer (Figure 5 of the document), achieving:

• ✅ Direct PCB trace mounting (no magnetic ring or slotting required)
• ✅ Simplified structure and support for ±600A high current (Document 12.3)
• ✅ Saves >50% layout space compared to vertical Hall solutions

8. Essential Knowledge for Engineers in Selection

1. Version distinction:
   • -AAH-003: 100 mV/mT (high-field version, ±25mT)
   • -AAL-003: 280 mV/mT (low-field version, ±10mT)
2. Output mode:
   • Single-ended output: A_out (Pin1) to GND
   • Differential output: A_out minus CO_out (Pin8 = VDD/2)
3. PCB design key points:
   • Load capacitance ≤1000pF (otherwise bandwidth decreases)
   • VDD requires 100nF+100pF ceramic capacitor decoupling (Chapter 13 of the document)
4. Calibration suggestion: Document 12.4 recommends calibrating single-point offset through MCU (e.g., correcting output at 100A)
5. Risk avoidance:
   • Prohibition of supply voltage exceeding 6V (Table 1 of the document)
   • Reflow soldering must follow IPC/JEDEC J-STD-020 specification (Chapter 14 of the document)

Naming rule: MLX91205K (temperature grade) DC (SOIC8 package) -AAH-003 (sensitivity code) -RE/TU (packaging)

By integrating high bandwidth, planar magnetic field detection, and automotive-grade temperature stability, MLX91205KDC-AAH-003-RE/TU has become an innovative solution for compact high-current detection.