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Электронный компонент: A1183

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A1180 A1184
Preliminary Data Sheet
PRELIMINARY DATA SHEET
SUBJECT TO CHANGE WITHOUT NOTICE
Two-Wire, Programmable, Chopper-Stabilized,
Unipolar Hall-Effect Switch
See typical application drawing for UA pinning.
The A118X is a two-wire, unipolar, Hall-effect switch family designed
for use in high-temperature applications. This device uses a patented high
frequency chopper-stabilization technique on Allegro's new DABIC5
BiCMOS wafer fabrication process to achieve magnetic stability and to
eliminate offset inherent in single-element devices and from harsh-
application environments.
The A118X FAMILY of devices incorporates a programmability
function to allow for external trimming of the operate point. The
programming is performed after final packaging of the sensor and
placement of the Single In-Line Package (SIP) into the application. This
advanced feature allows for optimization of sensor switching performance
by effectively accounting for variations caused by magnet and SIP
placement tolerances.
These devices provide on-chip transient protection. A zener clamp on
the power supply protects against over-voltage conditions on the supply
line.
The output of the A118X FAMILY, with the exception of the A1180/2,
will switch HIGH in the presence of a sufficiently large south-pole magnetic
field and will switch LOW with the removal of the field. The A1180/2 has
the opposite polarity as the others, switching LOW in the presence of a
sufficient magnetic field and HIGH with the removal of the field.
Two package styles provide a magnetically optimized package for
most applications. Suffix "LH" is a miniature low profile package for
surface-mount applications; suffix "UA" is a three-lead ultra-mini Single
Inline Package (SIP) for through-hole mounting.
Factory programmed versions also available, see A1140/42/43/45.
Programming software and/or hardware demonstration kits also available
see ASEK-01 on the Allegro web site, www.allegromicro.com.
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
V
CC
............................................ 26.5 V
Reverse-Battery Voltage
V
RB
............................................. -18 V
Magnetic Flux Density
B .......................................... Unlimited
Package Power Dissipation
ja,
UA........................................ 206 C/W
LH
1
.........................................248 C/W
Junction Temperature, T
J
.................... +170C
Operating Temperature Range, T
A
Suffix "E" ....................... - 40 C to + 85 C
Suffix "L" ...................... - 40 C to + 150 C
Storage Temperature Range
T
S
.............................. -65 C to +170 C
FEATURES / BENEFITS
Chopper Stabilization
s
Extremely low switch-point drift
s
Low stress sensitivity
One-time external programmability
s
Operate Point
On-chip Protection
s
Supply transient protection
s
Robust ESD/EMC protection
s
Reverse-battery protection
On-board Voltage Regulator
s
3.8 V to 24 V operation
Order by complete part number (i.e. A1182LUA).
1
The "LH"
PPD is based on a 0.062" thick FR4, single-sided board using 2 oz. copper, with a 0.55 mm
2
area of copper attached to the ground lead.
TWO-WIRE, PROGRAMMABLE, UNIPOLAR HALL-EFFECT SWITCH FAMILY
(PRELIMINARY INFORMATION SUBJECT TO CHANGE)
Rev. 1.8 25 April 2003
Page 2
115 Northeast Cutoff, Box 15036
Worcester, Massachus etts 01615-0036 (508) 853-5000
Copyright 1993, 1995 Allegro MicroSystems, Inc.
CHARACTERISTICS
Valid over operating temperature range unless otherwise noted.
Limits
Part Number
Characteristics
Symbol
Test Conditions
Min.
Typ.
Max.
Units
ELECTRICAL CHARACTERISTICS
A118X FAMILY Supply Voltage
V
CC
Operating
3.8
-
24
V
I
GND(L)
Output I Low
5
-
6.9
mA
A1182/3/4
Supply Current
I
GND(H)
Output I High
12
-
17
mA
I
GND(L)
Output I Low
2
-
5
mA
A1180/1
2
Supply Current
I
GND(H)
Output I High
12
-
17
mA
Output Rise Time
3
t
r
R
L
=100 Ohms,
C
BYP
=0.1uF
-
20
-
us
Output Fall Time
3
t
f
R
L
=100 Ohms,
C
BYP
=0.1uF
-
20
-
us
Chopping Frequency
f
C
-
-
340
-
kHz
Power-Up Time
t
on
-
-
-
25
s
Power-Up State
POS
t < t
on,
t
r
< 5us,
no bypass capacitor
-
HIGH
-
-
A118X
Zener Voltage
V
Z
I = 10mA
28
36
40
V
MAGNETIC CHARACTERISTICS
Minimum Programmable
Operate Point
B
OPmin
60
G
Maximum Programmable
Operate Point
B
OPmax
B>B
op
,
I
GND
=Low (A1180/2)
I
GND
=High (A1181/3)
200
G
A1180/1/2/3
4
Switch Point Step Size
B
RES
-
8
G
Minimum Programmable
Operate Point
B
OPmin
300
G
Maximum Programmable
Operate Point
B
OPmax
B>B
op
,
I
GND
=High (A1184)
600
G
A1184
5
Switch Point Step Size
B
RES
-
16
G
Switch Point
-
5
-
Bit(s)
Number of Programming
Bits
-
Programming Lock
-
1
-
Bit(s)
Temperature Drift of B
OP
B
OP
A1180-A1183
+/-20
G
A118X
Hysterisis
B
HYS
B
OP
- B
RP
5
15
30
G
2
These are the A3161 current levels.
3
Typical rise and fall time of the Hall sensor is 1us, the true rise and fall time is dependent on the load circuit as indicated by the 20us specification.
4
Programming is typically performed at Ta = 25C and does not take into account temperature drift of the switch point. See
B
OP.
5
Programming is typically performed at Ta = 25C and does not take into account temperature drift of the sw itch point.
B
OP
has not yet been
characterized for the A1184 and may require additional tolerance due to the high magnetic switch points
.
TWO-WIRE, PROGRAMMABLE, UNIPOLAR HALL-EFFECT SWITCH FAMILY
(PRELIMINARY INFORMATION SUBJECT TO CHANGE)
Rev. 1.8 25 April 2003
Page 3
115 Northeast Cutoff, Box 15036
Worcester, Massachus etts 01615-0036 (508) 853-5000
Copyright 1993, 1995 Allegro MicroSystems, Inc.
FUNCTIONAL BLOCK DIAGRAM
Reg
Clock/Logi
c
AMP
S/H
LPF
Supply
GND
Programmmin
g
Logic
Program /
Lock
Offset
Adjust
To all
subcircuits
Optional
GND
("UA" ONLY-Pin 3)

0
Output Current
+I
0
Flux Density
+B
IccHigh
IccLow
B
op
B
rp
A1180/2 Hysteresis Curve
0
Output Current
+I
0
Flux Density
+B
IccHigh
IccLow
B
op
B
rp
A1181/3/4 Hysteresis Curve
TWO-WIRE, PROGRAMMABLE, UNIPOLAR HALL-EFFECT SWITCH FAMILY
(PRELIMINARY INFORMATION SUBJECT TO CHANGE)
Rev. 1.8 25 April 2003
Page 4
115 Northeast Cutoff, Box 15036
Worcester, Massachus etts 01615-0036 (508) 853-5000
Copyright 1993, 1995 Allegro MicroSystems, Inc.
Typical Characterization Data
All data is the average of 1 Lot, >1000 Units

Bop 85G trim
78
80
82
84
86
88
90
92
94
-40 C
25 C
85 C
Temperature (C)
Switch point (G)
Vcc=24v
Vcc= 12v
Vcc= 3.8v
Bop programming values
0
20
40
60
80
100
120
140
160
180
0
1
2
3
4
5
Significant Bit
Switch point (G)
Iccon
12
12.5
13
13.5
14
14.5
15
15.5
16
16.5
17
-40 C
25 C
85 C
Temperature (C)
Current (mA)
Vcc= 24v
Vcc= 12v
Vcc= 3.8v
Iccoff
5
5.2
5.4
5.6
5.8
6
6.2
6.4
6.6
6.8
-40 C
25 C
85 C
Temperature (C)
Current (mA)
Vcc =24v
Vcc =12v
Vcc =3.8v
TWO-WIRE, PROGRAMMABLE, UNIPOLAR HALL-EFFECT SWITCH FAMILY
(PRELIMINARY INFORMATION SUBJECT TO CHANGE)
Rev. 1.8 25 April 2003
Page 5
115 Northeast Cutoff, Box 15036
Worcester, Massachus etts 01615-0036 (508) 853-5000
Copyright 1993, 1995 Allegro MicroSystems, Inc.
Functional Description
Chopper-Stabilization Technique. A limiting factor for switch point accuracy when using Hall effect technology is the
small signal voltage developed across the Hall plate. This voltage is proportionally small relative to the offset that can be
produced at the output of the Hall sensor. This makes it difficult to process the signal and maintain an accurate, reliable
output over the specified temperature and voltage range.

Chopper Stabilization is a unique approach used to minimize Hall offset on the chip. The Allegro patented technique;
dynamic quadrature offset cancellation, removes key sources of the output drift induced by temperature and package
stress. This offset reduction technique is based on a signal modulation-demodulation process. The undesired offset
signal is separated from the magnetically induced signal in the frequency domain through modulation. The subsequent
demodulation acts as a modulation process for the offset causing the magnetically induced signal to recover its original
spectrum at base band while the dc offset becomes a high frequency signal. Then, using a low-pass filter the signal
passes while the modulated dc offset is suppressed.

The chopper stabilization technique uses a 170 kHz high frequency clock. The Hall plate chopping occurs on each clock
edge resulting in a 340 kHz chop frequency. The high frequency operation allows for a greater sampling, which produces
higher accuracy and faster signal processing capability. Using this chopper stabilization approach, the chip is de-
sensitized to the effects of temperature and stress. This technique produces devices that have an extremely stable
quiescent Hall output voltage, is immune to thermal stress, and has precise recoverability after temperature cycling. This
technique is made possible through the use of a BiCMOS process which allows the use of low offset and low noise
amplifiers in combination with high-density logic integration and sample and hold circuits.

The repeatability of switching with a magnetic field is slightly affected using a chopper technique. Allegro's high frequency
chopping approach minimizes the affect of jitter and makes it imperceptible in most applications. Applications that may
notice the degradation are those that require the precise sensing of alternating magnetic fields such as ring magnet speed
sensing. For those applications, Allegro recommends the "low jitter" family of digital sensors.

Regulator
Amplifier
Sample/
Hold
CLOCK
Hall Element
Concept of Dynamic Quadrature Offset Cancellation