■ FIGURE 17b. The
Hall effect sensor
IC’s outline drawing.
Artwork courtesy of
Allegro Microsystems.
■ FIGURE 17a. The Hall effect sensor
IC’s pin assignment. Artwork courtesy
of Allegro Microsystems.
nal block since it carries AC (has no
polarity) to the hinges for the tingling
or tactile missing pawn detection
method. If it seems strange to you that
this is AC in a battery powered project, remember, AC pulses the trans-
former’s input and it will not pass DC.
Turn the 10K pot (R9) to the middle of its range. One side of the pot is
shorted to the tap, so you increase or
decrease the resistance in the circuit
when you adjust the pot. You can test
the circuit with the DMM or touch it
with two fingers of one hand after
attaching the wires to the hinges. You
should get a strong
tingle in your fingers each time the
test LED illuminates.
The DMM will
measure a large
voltage and/or the
same frequency as
the 60 Hz oscillator. If you prefer a
less intense tingle,
you can increase
the value of the
pot to further limit
the current into
the base of
Q1. Conversely,
decreasing the
value of the pot
yields a more intense tingle.
Permanently install the battery
holder with Nylon screws and nuts
and solder the pins to the board.
Once you assemble and test the
PCB, insert the four wood screws (one
in each corner of the top wooden panel
with the PCB assembly), the longer
spacers, and the acrylic sheet aligned
HALL EFFECT IC AND SENSOR MANUFACTURERS
■ Allegro Microsystems — {Hall effect ■ CR Magnetics, Inc. — {DIN rail or ■ Micronas Intermetall — {Hall effect sen-sensors}; 115 Northeast Cutoff, Worcester, panel mount DC Hall effect current sors} Hans-Bunte-Strasse 19, P.O. Box 840,
MA 01606; (508) 853-5000. transducers modules} 3500 Scarlet Oak D-79108 Freiburg, Germany; 49-761-517-0;
Blvd, St. Louis, MO 63122; (636) 343-8518; Fax: 49-761-517-2174; www.intermetall.de.
Fax: (636) 343-5119; Email: sales@cr
magnetics.com.
■ American Electronic Components, Inc.
— {Hall effect sensors} 1101 Lafayette
Street, Elkhart, IN 46516; (574) 295-6330;
Toll Free: (888) 847-6552.
■ Amploc — {Hall effect current sensors}
P.O. Box 152, Goleta, CA 93116; (805)
964-9119.
■ Motion Sensors, Inc. (MSI) — {Hall
effect sensors} 786 Pitts Chapel Rd.,
Elizabeth City, NC 27909; (252) 331-2080;
Fax: (252) 331-1666; Email: info@motion
sensors.com.
■ F. W. Bell/Bell Technologies, Inc. — {Hall
effect sensors} A Division of Sypris Test &
Measurement; 6120 Hanging Moss Road,
Orlando, FL 32807; (407) 678-6900; Toll
Free: (800) 775-2550; Fax: (407) 678-0578.
■ Honeywell — {Hall effect sensors} 101
Columbia Road, Morristown, NJ 07962;
(973) 455-2000; Fax: (973) 455-4807. This
link describes an excellent book on the
subject published by Honeywell www.
sensorsportal.com/HTML/BOOKSTORE/
Hall_Effect_Sensors.htm.
■ Infineon — {High sensitivity Hall effect
sensors} Service Center: (866) 951-9519.
■ Optek, Inc. — {Hall effect sensors} North
American Headquarters Mexico and The
Americas, 1645 Wallace Drive, Carrollton,
TX 75006; (972) 323-2200; Toll Free: (800)
341-4747; Fax: (972) 323-2396; Email:
sensors@optekinc.com.
■ Cherry Electrical Products — {Hall effect
sensors} 11200 88th Avenue, Pleasant
Prairie, WI 53158; (262) 942-6500.
■ Melexis Microelectronic Integrated ■ Xensor Corporation — (Hall effect
Systems— {Hall effect sensors} 41 Locke sensors — single, dual, and triple) 530
Road, Concord, NH 03301; (603) 223-2362; South Henderson Road, Suite A, King of
Fax: (603) 223-9614. Prussia, PA 19406; www.xensor.com.
54
May 2007
