3121, 3122,
AND
3123
HALL-EFFECT SWITCHES
FOR HIGH-TEMPERATURE OPERATION
These Hall-effect switches are monolithic integrated circuits with
tighter magnetic specifications, designed to operate continuously over
extended temperatures to +150擄C, and are more stable with both tem-
perature and supply voltage changes. The unipolar switching character-
istic makes these devices ideal for use with a simple bar or rod magnet.
The three basic devices (A3121, A3122, and A3123) are identical except
for magnetic switch points.
Each device includes a voltage regulator for operation with supply
voltages of 4.5 volts to 24 volts, reverse battery protection diode, qua-
dratic Hall-voltage generator, temperature compensation circuitry, small-
signal amplifier, Schmitt trigger, and an open-collector output to sink up
to 25 mA. With suitable output pull up, they can be used with bipolar or
CMOS logic circuits. The A3121 is an improved replacement for the
UGx3113 and UGx3119.
The first character of the part number suffix determines the device
operating temperature range. Suffix 鈥楨鈥撯€?is for the automotive and
industrial temperature range of -40擄C to +85擄C. Suffix 鈥楲鈥撯€?is for the
automotive and military temperature range of -40擄C to +150擄C. Three
package styles provide a magnetically optimized package for most
applications. Suffix 鈥樷€揕T鈥?is a miniature SOT89/TO-243AA transistor
package for surface-mount applications; suffix 鈥樷€揢鈥?is a three-lead
plastic mini-SIP while suffix 鈥樷€揢A鈥?is a three-lead ultra-mini-SIP.
Data Sheet
27621.4B鈥?/div>
V
X
CC
1
2
3
GROUND
Dwg. PH-003A
Pinning is shown viewed from branded side.
OUTPUT
SUPPLY
FEATURES and BENEFITS
s
Superior Temp. Stability for Automotive or Industrial Applications
s
4.5 V to 24 V Operation 鈥?Needs Only An Unregulated Supply
s
Open-Collector 25 mA Output 鈥?Compatible with Digital Logic
s
Reverse Battery Protection
s
Activate with Small, Commercially Available Permanent Magnets
s
Solid-State Reliability 鈥?No Moving Parts
s
Small Size
s
Resistant to Physical Stress
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25
擄
C
Supply Voltage, V
CC
...........................
30 V
Reverse Battery Voltage, V
RCC
........
-30 V
Magnetic Flux Density, B .......
Unlimited
Output OFF Voltage, V
OUT
................
28 V
Reverse Output Voltage, V
OUT
........
-0.5 V
Continuous Output Current, I
OUT
...
25 mA
Suffix 鈥楨鈥撯€?.................
-40
擄
C to +85
擄
C
Suffix 鈥楲鈥撯€?...............
-40
擄
C to +150
擄
C
Storage Temperature Range,
T
S
..............................
-65
擄
C to +170
擄
C
Operating Temperature Range, T
A
The A3121xU is not for new design.
The A3122xU and A3123xU are last-time buy.
Orders accepted until April 15, 2002.
Always order by complete part number, e.g.,
A3121EU
.
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