It depends on the market.
Search a report on the net, I cannot paste the link here.
"“The magnetic sensor market consists of Hall-effect and magneto-resistive semiconductor ICs that are used to track rotational speed and linear angles in machines and devices, or to detect and process magnetic fields to establish positioning,” said Richard Dixon, principal analyst for MEMS & sensors at IHS.
“The sensors are utilised in a wide range of applications - from electronic systems and motors in cars, to compasses in cellphones and tablets, to the monitoring of current in solar inverters, to brushless direct-current (DC) motors in a range of medical systems such as ventilators, dialysis machines and centrifuges,” he notes.
The largest portion of the magnetic sensor market in 2011 was in the automotive segment, with revenue reaching $731.3 million, up 13 percent from $648.9 million in 2010. Growth was more robust in the joint wireless-consumer space, increasing by a staggering 50 percent to $549.9 million in 2011, up from $347.7 million in 2010.
The industrial-military-energy-medical sector generated $153.3 million, up 6 percent from $145.3 million in 2010. Also, the data processing segment went up 2.5 percent from $63.0 million to $64.6 million in 2011.
Another further 13 percent climb is predicted for 2012 when sensor revenue hits $1.7 billion. By 2016, revenue will amount to some $2.3 billion, equivalent to a five-year compound annual growth rate by then of 9.3 percent.
The market drivers for magnetic sensors can be classified into various categories. These include safety applications for the sensors include airbags in vehicles and fault detection in solar panels. Magnetic sensors can also be found to aid new functionality, comfort or intelligence, utilised in automotive seat-position memory, improved heading resolution for navigation systems in cars and cellphones, and quieter motors in medical equipment. Energy efficiency is similarly a major market driver of the sensors, found in intelligent fans in cars, as well as in higher-efficiency motors for industrial manufacturing and automation.
In the automotive segment sensors are used in multiple functions. For example, the sensors figure in the reduction of power consumption, especially as manufacturers face increasing pressure to reduce carbon emissions by fractions of a gram of carbon dioxide or other unwanted pollutants. One area of focus here is motors, which migrate from “always on” pulley systems with the associated friction, to electronic equivalents that can be controlled on demand. These motors at the same time migrate to more efficient and reliable brushed DC varieties that use multiple Hall sensors for their control or commutation.
Other implementations of magnetic sensors in cars include basic wheel-speed sensing for anti-lock braking systems (ABS), torque sensing in steering systems, electronic throttle-by-wire systems and multiple applications in car-battery monitoring.
Magnetic sensors are also big in multiple-axis-measurement electronic compasses, now found as a standard feature in cellphones and tablets equipped with global positioning systems (GPS).
Consumer electronics applications such as gaming consoles, laptops and geotagging-equipped digital still cameras will also benefit from the sensors.
Magnetic sensors also find major use in the measurement of currents and motion-control positioning, particularly in the burgeoning industrial motor space as well as for motor drives and solar inverter markets.
Other implementations for magnetic sensors include their use in data processing and peripherals, such as fax machines and printers; in consumer electronics, such as in white goods like coffee machines for water-level detection; and in various military, agricultural and transport applications."
This market has about 1.6 bil USD in 2012. The top suppliers of magnetic sensors last year were Asahi Micro Devices from Japan, Allegro MicroSystems of Massachusetts, part of Sanken Electric; Infineon Technologies AG of Germany, Micronas of Switzerland, Melexis NV of Belgium, and NXP Semiconductors of the Netherlands. Together these six suppliers accounted for 80 percent of the magnetic sensor IC market in 2011.
I can't say as I've ever read a comparison report on batches of similar sensors from those makers. Frankly as long as its well within engineering specifications and there are few bad components I think they're fairly equivalent given the ratings.
Now, the question is, who can produce the fastest and most sensitive but noise filtered sensors at the cheapest price, and supply them quickly to local manufacturers?
I primarily got into FSL because of their prototyping systems and ability to subsequently make small to HUGE lots of custom cut product at a reasonable price, and still integrate it into their tower systems or build it to stand alone. That's a service that has great demand among experimenters, robotics specialists (particularly those concerned with space, e.g. cubic inches), and some of their new lower power technologies that might have possibilities on the kind of small self driven systems I'm working on. If all goes well and a few years up the road I go to make tens of thousands of the things FSL is probably where I'll go to finish the design to board and mass produce the processing cages.
Maybe partly because it's a Texas company I can keep an eyeball on, but also because I've never heard any significant complaints about them from anyone credible.