US4881
CMOS Low Voltage High Sensitivity Latch
Preliminary Datasheet
Features and Benefits
•
•
•
•
•
•
•
•
•
Chopper stabilized amplifier stage
Optimized for BDC motor applications
New miniature package / thin, high reliability package
Operation down to 2.2V
CMOS for optimum stability, quality, and cost
Low I
DD
current
Applications
Solid state switch
Brushless DC motor commutation
Speed sensing
Ordering Information
Part No.
US4881
US4881
Temperature Suffix
Package
Temperature Range
E
SO or UA
-40 to 85
o
C Extended
L
SO or UA
-40 to 150
o
C Automotive
Contact factory or sales representative for legacy temperature code options
y
r
a
in
im
l
e
r
P
Functional Diagram
Description
The US4881 is a bipolar Hall effect sensor IC fab-
ricated from mixed signal CMOS technology. It
incorporates advanced chopper stabilization tech-
niques to provide accurate and stable magnetic
switch points. There are many applications for
this HED in addition to those listed above. The
design specifications and performance have been
optimized for commutation applications in brush-
less DC motors and automotive speed sensing.
The output transistor will be latched on (B
OP
) in
the presence of a sufficiently s
trong South pole
magnetic field facing the marked side of the pack-
age. Similarly, the output will be latched off (B
RP
)
in the presence of a North field.
SO Package
Pin 1 - V
D D
Pin 2 - Output
Pin 3 - GND
V
DD
Output
Voltage
Regulator
Chopper
GND
UA Package
Pin 1 - V
D D
Pin 2 - GND
Pin 3 - Output
The SOT-23 device is reversed from the UA
package. The SOT-23 output transistor will be
latched on (B
OP
) in the presence of a sufficiently
strong North pole magnetic field subjected to the
marked face.
Note:
Static sensitive device; please observe ESD precautions. Re -
verse V
DD
protection is not included. For reverse voltage protec -
tion, a 100Ω resistor in series with V
DD
is recommended.
US4881 CMOS Low Voltage High Sensitivity Latch
3901004881 Rev 1.5
24/July/01
Page 1
MICRO-ELECTRONICS [ Micro Electronics ]
