The Sl353 series sensor ICs 9internal circuits) have been designed to offer the user a small, versatile, digital hall0effect device operated by the magnetic field of a permanent magnet or an electromagnet. They have a low power requirement and are sited to many possible applications. They are able to operate from a supply voltage as low as 2.2 V helping with energy efficiency. They can respond to either a North or South pole. This helps reduce instillation time as the user does not need to identify the magnetic polarity.
The SLS353HT has been designed as a High Duty Cycle unit and is ideal for applications requiring a high switching speed and a lower current then standard Hall Effect sensors.
The SLS353LT has been designed as a very Low Duty Cycle unit and thus ideal for applications requiring a low switching speed but with a requirement to extend battery life and operate with an extremely low current drain.

Features:
Energy efficient: SL353HT 0.33 mA typical, SL353LT 1.8 μA typical
Push-pull output does not require external pull-up resistor
Non-chopper stabilized design
SOT-23 sub miniature package size requires less PCB space

Choose this micropower Hall effect sensor from Honeywell for reduced power consumption in your sensing applications. Its BiCMOS (bipolar complementary metal-oxide semiconductor) technology and an innovative timing circuit turn power on for only a short time to ensure a high degree of energy efficiency. The sensor is simple to install as it responds to either a north or south pole, meaning you don't have to identify magnet polarity beforehand. This unit is compatible with a low supply voltage of 2.2V, so it's suitable for use with mobile, battery-operated devices.

• Thermally balanced integrated circuit provides stable operation over a wide temperature range of -40°C to +85°C for use in demanding environments
• Omnipolar function makes it compatible with both high and low-duty cycles for improved versatility in use
• Miniature size requires less space on a PCB (printed circuit board) for maximum space efficiency

• Mobile printer head position sensing
• Remote battery-operated water meters
• Hand-held medical and dentistry equipment

No, the push-pull output doesn't need an external pull-up resistor and works with most electrical circuits for greater ease of use.

Hall Effect Sensors, Honeywell