MICRO POWER, ULTRA-SENSITIVE HALL SWITCH
FSH4917
FEATURES
Micro power design
Operation with North or South pole(omni polar)
2.4V to 5.5V battery operation
High sensitivity and high stability of the magnetic
switching points
High resistance to mechanical stress
Digital output signal
Good RF noise immunity
-40℃ to 85℃ operating temperature
Programming pin for switching detection of output
Package: SOT23-6L
GENERAL DESCRIPTION
The FSH4917 is an Integrated Hall Effect Sensor
designed specifically to meet the requirements of l o w -
power devices. e.g. as an On/Off switch in Cellular
Flip-Phones, with battery operating voltages of 2.4V –
5.5V.
Precise magnetic switching points and high temperature
stability are achieved through the unique design of the
internal circuit.
An onboard clock scheme is used to reduce the average
operating current of the IC.
During the operate phase the IC compares the
actual magnetic field detected with the internally
compensated switching points. The output is switched
at the end of each operating phase.
During the Stand-by phase the output stage is latched
and the current consumption of the device reduced to
some µA.
The IC switching behavior is Omni polar, i.e. it can be
switched on with either the North or South pole of a
magnet.
The PRG pin can be connected to VDD which holds the
output VO at a High level for B=0mT; conversely the
output VO can be inverted by connecting the PRG
pin to GND, which will hold the output VO at a Low
level for B=0mT. In this later case the presence of an
adequate magnetic field will cause the output VO to
switch to a High level (i.e. off state).
FUNCTIONAL BLOCK DIAGRAM
VDD
Awake & Sleep
Timing Logic
VOUT
Hall Plane
Dynamic Offset
Cancellation
Latch circuit
Chopper
Amplifier
Hysteresis
Latch
GND
PRG
TYPICAL APPLICATION CIRCUIT
6
PRG
5
GND
FSH4917
4
GND
_
0.1μF
Vout
3
50KΩ
Vco
1
GND
2
+
2.4-5.5V
Output
1/9
2006-12-22
FOSLINK [ FOSLINK SEMICONDUCTOR CO.,LTD ]
