If you’ve been following magnetic keyboards, you may have seen claims that TMR (Tunnel Magneto Resistance) is inferior to the traditional Hall Effect. In fact, our magnetic switches have always used TMR technology—from the very first Keychron Q1 HE to all our current magnetic keyboards.
You might wonder - why did we name it “HE” in our series and models, then? Here’s the reason: Early on, TMR wasn’t widely known. Using the widely known “HE” magnetic in the keyboard industry helped the market quickly understand our keyboard using magnetic switches — though our fundamental tech has always been TMR.
Why did we use TMR technology from the start, and what advantages does TMR have compared with the traditional Hall Effect?
In this blog, we’ll break down the key differences between TMR and Hall Effect. Read on to figure out which technology aligns best with your specific needs.
Differences Between TMR vs. Hall Effect
Both TMR (Tunnel Magneto Resistance) and Hall Effect are common magnetic sensing technologies, widely used in scenarios like keyboard magnetic switches, sensors, and precision detection. Each has its own set of advantages and disadvantages:
Advantages of TMR
1. Higher Sensitivity: TMR resistance changes significantly with magnetic fields, with far higher signal amplitude than Hall.
2. Excellent Signal-to-Noise Ratio (SNR): With stronger output signals, its anti-interference capabilities and accuracy are generally superior to Hall.
3. Low Power Consumption: In low-power designs, the TMR sensor consumes less energy than the Hall Effect sensor, making them particularly suitable for battery-powered devices.
4. Fast Response Speed: Ideal for high-speed magnetic field detection with minimal latency.
5. Fast Start-up Time: Supports matrix scanning by powering rows or columns of sensors sequentially, further reducing power draw.
Drawbacks of TMR
1. Higher Cost: Complex manufacturing process, resulting in higher wafer and packaging costs than Hall.
2. Process and Temperature Sensitivity: TMR devices require high process consistency and temperature drift, making mass production more challenging than Hall Effect Sensors.
3. Applications are very new compared to Hall's decades of widespread adoption. TMR remains an emerging technology in some fields (e.g., magnetic keyboard switches), with relatively fewer supply chains that can support.
Advantages of the Hall Effect
1. Lower Cost: Mature silicon manufacturing and mass production result in low prices and a well-established supply chain.
2. Simple Circuitry: It directly outputs voltage signals, with relatively low requirements for peripheral circuits.
Drawbacks of Hall Effect
1. Moderate Sensitivity: A relatively strong magnetic field is required to achieve stable output, and the resolution is limited.
2. Higher Power Consumption: Compared with TMR, it consumes more power under the same conditions.
3. More Noise-Prone: Weak signals require amplification and are susceptible to noise interference.
4. Slower Start-up Time: Not suitable for matrix scanning methods with row-by-row or column-by-column power supply of sensors sequentially.
Here's the quick comparison:
| Feature | TMR Sensor | Hall Effect Sensor |
|---|---|---|
| Sensitivity | High | Moderate |
| Signal-to-noise | Excellent | Fair |
| Power Consumption | Low | Higher |
| Response speed & Startup | Fast | Slower |
| Cost | Higher | Lower |
| Supply Maturity | Emerging | Established |
Conclusion
If you value cost-effectiveness, a mature supply chain, and proven reliability, Hall Effect should be a better option.
However, if you’re after high precision, low power consumption, and a superior experience, TMR is the preferred choice.
Overall, TMR holds clear advantages, though it comes at a higher cost.
FAQs
Why We Named It “HE” In Our Models?
Early on, TMR wasn’t widely known. Using the widely known “HE” magnetic in the keyboard industry helped the market quickly understand our magnetic switches, though our fundamental tech has always been TMR.
Looking for a magnetic keyboard with TMR technology?
All Keychron magnetic keyboards adopt TMR technology for superior precision and performance. Explore the collection for high-quality, affordable choices!