ALLEGRO A3260_06

A3260
2-Wire Chopper Stabilized
Precision Hall Effect Bipolar Switch
Last Time Buy
These parts are in production but have been determined to be
LAST TIME BUY. This classification indicates that the product is
obsolete and notice has been given. Sale of this device is currently
restricted to existing customer applications. The device should not be
purchased for new design applications because of obsolescence in the
near future. Samples are no longer available.
Date of status change: October 31, 2006
Deadline for receipt of LAST TIME BUY orders: April 27, 2007
Recommended Substitutions:
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The
information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
Data Sheet
27631.50d
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT BIPOLAR SWITCH
Suffix Code 'LH' Pinning
(SOT23W)
3
X
NC
GROUND
NO (INTERNAL)
CONNECTION
2
SUPPLY
1
Dwg. PH-003-5
Pinning is shown viewed from branded side.
The A3260-- Hall-effect bipolar switch is an extremely
temperature-stable and stress-resistant sensor especially suited for
operation over extended temperature ranges to +150°C. Superior
high-temperature performance is made possible through dynamic
offset cancellation, which reduces the residual offset voltage normally
caused by device overmolding, temperature dependencies, and thermal
stress.
The device includes on a single silicon chip a voltage regulator,
Hall-voltage generator, small-signal amplifier, chopper stabilization,
Schmitt trigger, and a constant-current open-collector output. A south
pole of sufficient strength will turn the output OFF. An on-board
regulator permits operation with supply voltages of 3.5 to 24 volts.
Noise radiation is limited by control of the output current slew rate.
The first character of the part number suffix determines the device
operating temperature range; suffix ‘E–’ is -40°C to +85°C and ‘L–’ is
-40°C to +150°C. Two package styles provide a magnetically optimized package for most applications. Suffix ‘–LH’ is a miniature
SOT23W low-profile surface-mount package, while suffix ‘–UA’ is a
three-lead ultra-mini-SIP for through-hole mounting.
FEATURES
ABSOLUTE MAXIMUM RATINGS
at TA=+25°C
Supply Voltage, VCC ........................... 27 V
Reverse Battery Voltage, VRCC .......... -16 V
Magnetic Flux Density, B ........... Unlimited
Package Power Dissipation, PD . See Graph
Junction Temperature, TJ ............... +165°C
Operating Temperature Range, TA
Suffix ‘E–’ .................. -40°C to +85°C
Suffix ‘L–’ ................ -40°C to +150°C
Storage Temperature Range,
TS .............................. -65°C to +170°C
■
■
■
■
■
■
■
■
Internal Current Regulator for 2-Wire Operation
Output Slew Rate Controlled
Resistant to Physical Stress
Superior Temperature Stability
Operation From Unregulated Supply
Reverse Battery Protection
Solid-State Reliability
Small Size
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
FUNCTIONAL BLOCK DIAGRAM
SUPPLY
SAMPLE
& HOLD
DYNAMIC
OFFSET CANCELLATION
X
LOW-PASS
FILTER
TO ALL
SUBCIRCUITS
REG.
GROUND
Dwg. FH-020-
Selection Guide
Part Number1
Pb-Free
Packing 2
Mounting
Ambient, T A
(°C)
A3260ELHLT
–
7-in. reel, 3000 pieces/reel
3-pin SOT23W surface mount
–40 to 85
A3260EUA
–
Bulk, 500 pieces/bag
3-pin SIP through hole
–40 to 85
1Certain variants cited in this footnote are in production but have been determined to be LAST TIME BUY. This classification
indicates that the product is obsolete and notice has been given. Sale of this device is currently restricted to existing
customer applications. The variants should not be purchased for new design applications because of obsolescence in the
near future. Samples are no longer available. Status date change October 31, 2006. Deadline for receipt of LAST TIME BUY
orders is April 27, 2007. These variants include: A3260ELHLT and A3260EUA. Variants A3260LLHLT and A3260LUA are
discontinued.
2Contact
2
Allegro for additional packing options.
115 Northeast Cutoff, Box 15036
W
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2002, 2006 Allegro MicroSystems, Inc.
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
ELECTRICAL CHARACTERISTICS over operating supply voltage and temperature ranges.
Limits
Characteristic
Symbol
Supply Voltage
VCC
Output Current
Chopping Frequency
Output Slew Rate
Test Conditions
Min.
Typ.
Max.
Units
Operating
3.5
12
24
V
IGND(L)
B > BOP
-4.0
-6.5
-8.0
mA
IGND(H)
B < BRP
-11
-14.5
-18
mA
–
340
–
kHz
fC
di/dt
CL = 20 pF
0.5
—
2.0
mA/µs
Output Settling Time
tsd
CL = 20 pF
—
—
20
µs
Reverse Battery Current
ICC
VRCC = -16 V
–
–
-15
mA
NOTES: 1. BOP = operate point (output turns OFF); BRP = release point (output turns ON).
2. Typical Data is at TA = +25°C and VCC = 12 V and is for design information only.
MAGNETIC CHARACTERISTICS over operating supply voltage and temperature ranges.
Limits
Characteristic
Symbol
Operate Point
Test Conditions
Min.
Typ.
Max.
Units
BOP
–
10
40
G
Release Point
BRP
-40
-10
–
G
Hysteresis
Bhys
2.0
20
–
G
BOP - BRP
NOTES: 1. Typical Data is at TA = +25°C and VCC = 12 V and is for design information only.
2. 1 gauss (G) is exactly equal to 0.1 millitesla (mT).
www.allegromicro.com
3
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
SENSOR LOCATIONS
Package Designators “UA”
Package Designator “LH”
ACTIVE AREA DEPTH
0.011"
0.28 mm
NOM
ACTIVE AREA DEPTH
0.059"
1.49 mm
0.0195"
0.50 mm
NOM
3
0.080"
2.04 mm
0.038"
0.96 mm
0.056"
1.44 mm
A
1
A
2
Dwg. MH-025
BRANDED
SURFACE
1
2
3
Dwg. MH-011-9B
Although sensor location is accurate to three sigma for a
particular design, product improvements may result in small
changes to sensor location.
Allegro
ALLOWABLE PACKAGE POWER DISSIPATION in MILLIWATTS
800
700
Suffix "–UA"
R TJA = 165°C/W
600
500
Suffix "–LH"
R TJA = 228°C/W
400
300
200
Suffix "E–"
100
Suffix "L–"
0
20
40
60
100
80
120
AMBIENT TEMPERATURE in °C
140
160
180
Dwg. GH-046-2D
4
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
FUNCTIONAL DESCRIPTION
Chopper-Stabilized Technique. These devices use a
proprietary dynamic offset cancellation technique, with an
internal high-frequency clock to reduce the residual offset
voltage of the Hall element that is normally caused by device
overmolding, temperature dependencies, and thermal stress.
This technique produces devices that have an extremely stable
quiescent Hall output voltage, are immune to thermal stress, and
have precise recoverability after temperature cycling. This
technique will also slightly degrade the device output repeatability.
SAMPLE
& HOLD
REG
X
The Hall element can be considered as a resistor array
similar to a Wheatstone bridge. A large portion of the offset is
a result of the mismatching of these resistors. The chopperstabilizing technique cancels the mismatching of the resistors by
changing the direction of the current flowing through the Hall
plate and Hall voltage measurement taps, while maintaining the
Hall-voltage signal that is induced by the external magnetic
flux. The signal is, then, captured by a sample-and-hold circuit.
Powering up in the absence of a magnetic field (less than
BOP and higher than BRP) will allow an indeterminate output
state. The correct state is warranted after the first excursion
beyond BOP or BRP.
Bipolar switches may switch on removal of field but
require field reversal for reliable operation over temperature
range; latches will not switch on removal of magnetic field.
B
+V
—
HALL
VOLTAGE
+
Dwg. AH-011-2
+I
IOUT + ICC
OUTPUT CURRENT
Operation. The output of these devices turns ON when a
magnetic field (north pole) perpendicular to the Hall sensor
exceeds the release point threshold (BRP). After turn-ON, the
output will source current equal to the device operating current
plus a current source (IGND(H)). When the magnetic field is
increased (south pole) above the operate point (BOP), the output
will source current equal to the Hall-effect sensor operating
current with the current source turned OFF (IGND(L)). Note
especially that release can occur when the magnetic field is
removed but to ensure release, a field reversal is required. The
difference in the magnetic operate and release points is the
hysteresis (Bhys) of the device. The hysteresis allows clean
switching of the output even in the presence of external mechanical vibration or electrical noise.
Dwg. EH-012
BOP
BRP
ICC
0
-B
0
FLUX DENSITY
www.allegromicro.com
+B
Dwg. GH-034-6
5
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
APPLICATIONS INFORMATION
It is strongly recommended that an external bypass capacitor be connected (in close proximity to the Hall sensor) between
the supply and ground of the device to reduce both external
noise and noise generated by the chopper-stabilization technique.
'UA' PACKAGE
–
+
3
2
X
0.95 V
0.1 µF
100 Ω
1
SUPPLY
Dwg. EH-011-2A
Extensive applications information for Hall-effect sensors is available in:
• Hall-Effect IC Applications Guide, Application Note 27701;
• Hall-Effect Devices: Soldering, Gluing, Potting, Encapsulating, and Lead Forming, Application Note 27703.1;
• Soldering of Through-Hole Hall-Sensor Dervices, Application Note 27703; and
• Soldering of Surface-Mount Hall-Sensor Devices, Application Note 27703.2.
More detailed descriptions of the chopper-stabilized circuit operation can be found in:
• Monolithic Magnetic Hall Sensor Using Dynamic Quadrature Offset Cancelation, Technical Paper STP 97-10; and
• Chopper-Stabilized Amplifiers With A Track-and-Hold Signal Demodulator, Technical Paper STP 99-1.
All are provided at
www.allegromicro.com
6
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
PACKAGE DESIGNATOR 'LH'
(fits SC-59A solder-pad layout)
Dimensions in Inches
(for reference only)
Dimensions in Millimeters
(controlling dimensions)
0.122
0.114
3.10
2.90
0.020
0.012
0.083
0.073
0.50
0.30
3
1
2
0.118
0.106
2.10
1.85
0.010
BSC
3
1
2
3.00
2.70
GAUGE PLANE
REF
0° TO 8°
0.037
0.006
0.000
SEATING PLANE
0.55
0.010
REF
0.045
0.032
MIN
BSC
0.0079
0.0050
0.15
0.00
0.20
0.127
1.13
0.87
Dwg. MA-010-3D in
Dwg. MA-010-3D mm
0.028
0.70
3
3
0.039
1.00
0.094
1
NOTES: 1.
2.
3.
4.
5.
0.25
0° TO 8°
0.95
MIN
BSC
BSC
GAUGE PLANE
SEATING PLANE
0.022
0.25
2
2.40
1
2
0.037
0.95
Dwg. MA-011-3 in
Dwg. MA-011-3 mm
Tolerances on package height and width represent allowable mold offsets. Dimensions given are measured at the widest point (parting line).
Exact body and lead configuration at vendor’s option within limits shown.
Height does not include mold gate flash.
Where no tolerance is specified, dimension is nominal.
Add "LT" to part number for tape and reel.
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7
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
PACKAGE DESIGNATOR ‘UA’
Dimensions in Millimeters
(for reference only)
Dimensions in Inches
(controlling dimensions)
0.164
0.159
4.17
4.04
0.062
0.058
45o
1.57
1.47
45o
0.122
0.117
3.10
2.97
45o
45o
0.085
1
2
3
0.031
2.16
1
2
3
0.640
0.600
16.26
15.24
0.0173
0.0138
0.0189
0.0142
SEE NOTE
BSC
0.44
0.35
0.48
0.36
SEE NOTE
1.27
0.050
Dwg. MH-014E in
BSC
NOTES: 1. Tolerances on package height and width represent
allowable mold offsets. Dimensions given are
measured at the widest point (parting line).
2. Exact body and lead configuration at vendor’s option
within limits shown.
3. Height does not include mold gate flash.
4. Recommended minimum PWB hole diameter to clear
transition area is 0.035" (0.89 mm).
5. Where no tolerance is specified, dimension is nominal.
6. Supplied in bulk pack (500 pieces per bag).
8
0.79
MAX
MAX
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Dwg. MH-014E mm
3260
2-WIRE, CHOPPER-STABILIZED,
PRECISION HALL-EFFECT
BIPOLAR SWITCH
Suffix Code 'UA' Pinning
(ultra-mini SIP)
2
GROUND
3
GROUND
1
SUPPLY
X
Dwg. PH-003-7A
Pinning is shown viewed from branded side.
The products described herein are manufactured under one or
more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283;
5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719;
5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents
pending.
Allegro MicroSystems, Inc. reserves the right to make, from time to
time, such departures from the detail specifications as may be
required to permit improvements in the performance, reliability, or
manufacturability of its products. Before placing an order, the user is
cautioned to verify that the information being relied upon is current.
Allegro products are not authorized for use as critical components
in life-support appliances, devices, or systems without express written
approval.
The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights
of third parties that may result from its use.
www.allegromicro.com
9