Minneapolis, Minn. – Honeywell has claimed the industry’s first Nanopower anisotropic magnetoresistive (AMR) sensor ICs that provide the highest level of magnetic sensitivity (as low as 7 Gauss typical) while requiring only 360 nanoamps (nA). Offering low power requirements together with smaller packaging and higher durability and reliability than reed switches at the same sensitivity and about the same cost, the Nanopower Series targets battery-powered applications where previously only reed switches could be used due to very low power requirements and large air gaps.
Applications include water and gas meters, electricity meters, industrial smoke detectors, exercise equipment, security systems, handheld computers, scanners, as well as white goods such as dishwashers, microwaves, washing machines, refrigerators and coffee machines, and medical equipment such as hospital beds, medication dispensing cabinets, infusion pumps, and consumer electronics such as notebook computers, tablets, and cordless speakers.
The Nanopower sensor ICs can also be used as alternatives to Hall-effect sensors. The sensors’ higher sensitivity allows them to sense air gaps two times the distance of Hall-effect sensors. This delivers greater design flexibility and offers cost savings by allowing for the use of smaller or lower strength magnets.
The Nanopower Series is available in two magnetic sensitivities. The ultra-high sensitivity SM351LT offers a very low current draw of 360 nA typical, and sensitivity of 7 Gauss typical operate and 11 Gauss maximum. The very high sensitivity SM353LT features a low current draw of 310 nA typical, and sensitivity of 14 Gauss typical operate and 20 Gauss maximum. The sensor ICs are house in SOT-23 packages, measuring 2.9 x 2.8 x 1.45 mm.
Omni-polarity allows the sensor to be activated by either a north or south pole, eliminating the need for the magnet polarity to be identified, which simplifies installation and potentially reduces system cost, said Honeywell. In addition, the push-pull (CMOS) output does not require external resistors, making it easier and more cost-effective to operate. The non-chopper stabilized design eliminates electrical noise generated by the sensor.
The subminiature SOT-23 surface mount package, supplied on tape and reel (3000 units per reel), is smaller than most reed switches. This allows for use in automated pick-and-place component installation and can reduce production costs.
Availability: Available now through Honeywell’s distribution network.
Pricing: Contact distributors for pricing.