Wave goodbye to the mechanical switch

Micronas has introduced a new Hall-effect switch, called HAL 1000, for position and speed measurements that can replace traditional mechanical micro switches. Micronas is a manufacturer of Hall sensors based on submicron CMOS processes, which allows them to integrate the Hall plate, logic circuitry, DSP, and EEPROM on one chip.

The new sensor can be used in applications such as switches in safety belts, door locks, ignition locks, and brake lights. The Hall-effect switches are also able to measure velocity with high accuracy even at low speeds. This makes the HAL 1000 a good choice for navigation systems, which deliver the precise velocity signals required to compute the exact position of a car.

Micronas was the first company to implement an active chopper offset compensation technique to eliminate piezo offsets, which often occur after thermal cycling, overmolding, or potting the IC. This results in precise switching devices that can function flawlessly over a wide temperature range with excellent long-term stability. Operating temperatures range from –40 to +150 °C, which meets the requirements for automotive applications.

The solid-state alternative to mechanical micro switches utilises a contactless switch principle, critical for applications in harsh environments where devices are subject to vibrations, shocks, dirt, moisture, high temperatures and electromagnetic interference. Integrated stabilisation and protection circuitry allows the devices to operate with noisy supply voltages without being distorted by high-frequency electromagnetic radiation. Every pin of the IC is protected against short-circuits and reverse polarity.

The HAL 1000 is the latest member of Micronas’ ‘Total Compensation Of System Tolerances (TCOST)’ family of Hall sensors. TCOST describes one of the unique features of the sensor: an EEPROM integrated on the chip. This allows an automatic electronic inline adjustment of the sensor parameters in the customer’s manufacturing line, eliminating magnetic and mechanical tolerances of the customer’s assembly.

The new Hall sensor is a programmable IC that switches its output low or high depending on the external magnetic field. The versatile programmability of the sensor IC allows it to be used in many different automotive and industrial applications. Features like output polarity, response to south or north polarity, hystereses, and temperature compensation of the switching points can be set by the customers. Because of this, they don’t need different devices for different applications thus reducing development, logistics, and qualification efforts.

IC samples and application kits for programming the IC are readily available. The contactless switch is housed in a small 3-pin lead TO-92UT package and is priced at less than US $ 1.50 for quantities above 500.000 units.

Micronas are at www.micronas.com