3150 Datasheet, PDF (1/12 Pages) Allegro MicroSystems – PROGRAMMABLE, CHOPPERSTABILIZED, HALL-EFFECT SWITCH

3150
PROGRAMMABLE, CHOPPER-
STABILIZED, HALL-EFFECT SWITCH
The A3150JLT and A3150JUA programmable switches provide
tooth/valley recognition in large gear-tooth sensing applications. Each
sensor consists of a single element, chopper-stabilized Hall-effect IC
that can be programmed to the desired magnetic switch point, opti-
mizing sensor airgap and timing accuracy performance after final
PTCT
packaging. The small package can be easily assembled and used in
V
T _CC
UC ^. ₁
2
3
PRODE ^ONsLiYgn _{Dwg. PH-003-2}
ED _NC de _{PRELIMINARY INFORMATION}
U _{E (subject to change without notice)}
IN ^{R w April 12, 1999}
NT ^{FE r ne} _{ABSOLUTE MAXIMUM RATINGS}
CO ^{RE fo at TA = 25°C}
Supply Voltage, V_CC ........................... 26.5 V
0 _{Reverse Supply Voltage, VRCC ............ -30 V}
IS ^{R 5 Overvoltage Supply Current, ICC ..... 100 mA}
D ^{O 2 Magnetic Flux Density, B ............ Unlimited}
F ^{3 Output Current, IOUT ..... Internally Limited}
Output OFF Voltage, V_OUT ................. 26.5 V
A _{Reverse Output Current, IROUT ......... -50 mA}
— ^e Operating Temperature Range,
T_A ............................... -40°C to +115°C
Us ^{Storage Temperature, TS ................... +170°C}
conjunction with a wide variety of gear/target shapes and sizes. The
two devices differ only in package style.
The sensing technology used for this sensor is Hall-effect based.
The sensor incorporates a single-element Hall IC that switches in
response to magnetic signals created by a ferrous target. The program-
mability of the circuit eliminates magnet and system offsets such as
those caused by tilt yet provides zero-speed detection capabilities
without the associated running jitter inherent in classical digital solu-
tions.
A proprietary dynamic offset cancelation technique, with an
internal high-frequency clock, reduces the residual offset voltage,
which is normally caused by device overmolding, temperature
dependancies, and thermal stress. This technique produces devices that
have an extremely stable quiescent output voltage, are immune to
mechanical stress, and have precise recoverability after temperature
cycling. Many problems normally associated with low-level analog
signals are minimized by having the Hall element and amplifier in a
single chip. Output precision is obtained by internal gain adjustments
during the manufacturing process and operate-point programming in the
user’s application.
This sensor system is ideal for use in gathering speed, position, and
timing information using gear-tooth-based configurations. The
A3150JLT/JUA are particularly suited to those applications that require
accurate duty cycle control or accurate edge detection. The lower
vibration sensitivity also makes these devices extremely useful for
transmission speed sensing.
Continued next page
Always order by complete part number: the prefix 'A' + the basic four-digit
part number + a suffix to indicate operating temperature range +
a suffix to indicate package style, e.g., A3150JLT .