GENERAL DESCRIPTION
MA278 are integrated Hall sensors with output drivers, mainly designed for electronic
commutation of brush-less DC Fan. This IC is using HV BCD process internally includes the
regulator, protecting diode, Hall plate, amplifier, comparator, and a pair of complementary
open-Drain outputs (DO, DOB).
While the magnetic flux density (B) is larger than operate point (Bop), DO will turn on
(low), and meanwhile DOB will turn off (high). Each output is latched until B is lower than
release point (Brp), and then DO, DOB transfer each state. For DC fan application,
sometimes need to test power reverse connection condition. Internal diode only protects
chip-side but not for coil-side. If necessary, add one external diode to block the reverse
current from coil-side.

 FEATURES
- On-chip Hall effect sensor with two different sensitivity and hysteresis settings
- Wide operating voltage range: 4.0V~20V
- Output sink current up to 0.4A
- -40°C to 85°C operating temperature
- Low Profile SIP-4L Packages( Green and Lead Free )