Sensors / Detectors / Transducers
Hall-Effect Latch features single push-pull output.
Press Release Summary:
Operating from 1.65-3.5 V without external pull-up resistor, Model A1174 features internally or externally controlled sample and sleep periods for track ball/scroll bar applications. When sufficient positive magnetic field is present on device, output transitions to low state until negative field of sufficient strength latches device output into high state. Housed in 6-pin MLP microleadframe package, unit is suitable for portable devices that employ rotational detection systems.
Original Press Release:
Allegro MicroSystems, Inc. Announces New Micro-Power Hall-Effect Latch
With Internally or Externally Controlled Sample and Sleep Periods for Track Ball/Scroll Bar Applications
Worcester, MA - August 5, 2008 - Allegro® announces a new ultrasensitive, Hall-effect latch for use in portable devices that employ rotational detection systems with a power supply voltage between 1.65 V and 3.5 V. This new device has a single push-pull output structure and does not require an external pull-up resistor for reliable operation. When a sufficient positive magnetic field is present on the device, the device output transitions to the low state and is latched in this state until a negative field of sufficient strength latches the device output into the high state. The latched output is ideal when using multiple sensors in rotational speed and direction sensing systems in portable devices.
Allegro's A1174 device includes an innovative clocking scheme that will minimize power consumption in portable devices. The device can be set in various working modes by using the external clock and dual clock pins. In dual clock mode the device switches between predefined slow and fast sampling rates. When rotation is detected, the device will sample in fast mode. The device will transition to slow sampling mode if the rotation stops.
In external clocking mode the user clocks the device to achieve the desired on and off time to control average power. This manual clocking also helps achieve synchronous clocking of multiple devices allowing for a defined phase relationship between the output transitions of each device in direction detection systems. By using either dual clocking mode or external clocking mode the average current can be reduced by 10 times over a standard micro-power latch, making the Allegro A1174 an industry leader for power consumption.
Improved magnetic switchpoint stability is made possible through dynamic offset cancellation using chopper stabilization, which reduces the residual offset voltage normally caused by device over molding, temperature dependencies, and thermal stress.
Targeted at the communications and consumer electronics market, Allegro's new A1174 Hall-effect latch is priced at $0.43 in quantities of 1,000 and has an 8-10 week lead-time to market. It is available in a lead (Pb) free (leadframe plating Nickel Palladium) 6-pin MLP microleadframe package for surface mount, with exposed pad for enhanced thermal dissipation.
For additional information on this new device, please access the datasheet at the following link: A1174
About Allegro
Allegro MicroSystems, Inc. is leader in developing, manufacturing and marketing high-performance power integrated circuits and integrated Hall-effect magnetic sensors. Allegro's innovative solutions serve high-growth applications within the automotive, communications, computer/office automation, consumer and industrial markets. Allegro is headquartered in Worchester, Massachusetts (USA) with design and applications center located in North and South America, Asia, and Europe. Further information about Allegro can be found at www.allegromicro.com.
