A3185EU - Allegro MicroSystems, Inc.

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE OPERATION

These Hall-effect latches are extremely temperature-stable and stress-

resistant sensors especially suited for operation over extended temperature

ranges to +150°C. Superior high-temperature performance is made possible

through a novel Schmitt trigger circuit that maintains operate and release

point symmetry by compensating for temperature changes in the Hall ele-

ment. Additionally, internal compensation provides magnetic switch points

that become more sensitive with temperature, hence offsetting the usual

degradation of the magnetic field with temperature. The symmetry capability

makes these devices ideal for use in pulse-counting applications where duty

cycle is an important parameter. The four basic devices (3185, 3187, 3188,

and 3189) are identical except for magnetic switch points.

Each device includes on a single silicon chip a voltage regulator, qua-

dratic Hall-voltage generator, temperature compensation circuit, signal

amplifier, Schmitt trigger, and a buffered open-collector output to sink up to

25 mA. The on-board regulator permits operation with supply voltages of 3.8

to 24 volts.

The first character of the part number suffix determines the device

operating temperature range. Suffix ‘E–’ is for -40°C to +85°C, and suffix

‘L–’ is for -40°C to +150°C. Three package styles provide a magnetically

optimized package for most applications. Suffix ‘–LT’ is a miniature SOT-

89/TO-243AA transistor package for surface-mount applications; suffix ‘–U’

is a three-lead plastic mini-SIP, while suffix ‘–UA’ is a three-lead ultra-mini-

SIP.

Data Sheet

27609.2A

ABSOLUTE MAXIMUM RATINGS

at T

A = +25°C

Supply Voltage, VCC ............................ 30 V

Reverse Battery Voltage, VRCC ........... -30 V

Magnetic Flux Density, B ........... Unlimited

Output OFF Voltage, VOUT .................. 30 V

Reverse Output Voltage, VOUT .......... -0.5 V

Continuous Output Current, IOUT ..... 25 mA

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

FEATURES

■ Symmetrical Switch Points

■ Superior Temperature Stability

■ Operation From Unregulated Supply

■ Open-Collector 25 mA Output

■ Reverse Battery Protection

■ Activate With Small, Commercially Available Permanent Magnets

■ Solid-State Reliability

■ Small Size

■ Resistant to Physical Stress

Pinning is shown viewed from branded side.

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., A3185ELT .

3185

THRU

3189

Dwg. PH-003A

SUPPLY

VCC

GROUND

OUTPUT

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

ELECTRICAL CHARACTERISTICS over operating temperature range, at VCC = 12 V.

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Supply Voltage VCC Operating 3.8 — 24 V

Output Saturation Voltage VOUT(SAT) IOUT = 20 mA, B > BOP — 175 400 mV

Output Leakage Current IOFF VOUT = 24 V, B < BRP — 0.05 5.0 µA

Supply Current ICC B < BRP (Output OFF) — 4.75 8.0 mA

B > BOP (Output ON) — 5.7 — mA

Output Rise Time trRL = 820 Ω, CL = 20 pF — 100 — ns

Output Fall Time tfRL = 820 Ω, CL = 20 pF — 100 — ns

MAGNETIC CHARACTERISTICS in gauss over operating supply voltage range.

Part Numbers*

A3185 A3187 A3188 A3189

Characteristic Min. Max. Min. Max. Min. Max. Min. Max.

BOP at TA = 25°C 170 270 50 150 100 180 50 230

over operating temp. range 140 300 50 175 80 200 50 250

BRP at TA = 25°C -270 -170 -150 -50 -180 -100 -230 -50

over operating temp. range -300 -140 -175 -50 -200 -80 -250 -50

Bhys at TA = 25°C 340 540 100 300 200 360 100 460

over operating temp. range 280 600 100 350 160 400 100 500

FUNCTIONAL BLOCK DIAGRAM

NOTES: BOP = operate point (output turns ON); BRP = release point (output turns OFF); Bhys = hysteresis (BOP - BRP).

As used here, negative flux densities are defined as less than zero (algebraic convention).

*Complete part number includes a suffix to identify operating temperature range (E or L) and package type ( LT, U, or UA).

VCC

REG.

Dwg. FH-005-3

GROUND

OUTPUT

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

TYPICAL OPERATING CHARACTERISTICS

A3185* SWITCH POINTS A3187* SWITCH POINTS

* Complete part number includes a suffix denoting operating temperature range (E or L) and package type (LT, U, or UA).

OUTPUT SATURATION VOLTAGE

SUPPLY CURRENT

OPERATE POINT

050 100

AMBIENT TEMPERATURE IN °C

-50

Dwg. GH-027

SWITCH POINT IN GAUSS

100

-50

-100

OPERATE POINT

RELEASE POINT

V = 12 V

150

-150

-25 25 75 125

025 50 75 100

AMBIENT TEMPERATURE IN °C

-50

Dwg. GH-028

125

-25

V = 12 V

B ≤ B

SUPPLY CURRENT IN mA

7.0

6.0

5.0

4.0

B ≥ B

150

0255075

100

300

AMBIENT TEMPERATURE IN °C

200

100

-50

Dwg. GH-029

SATURATION VOLTAGE IN mV

150

-25 125

I = 20 mA

V = 4.5–24 V

OUT

10 15 20 25

SUPPLY VOLTAGE IN VOLTS

Dwg. GH-037

CHANGE IN OPERATE POINT IN GAUSS

-5.0

5.0

T = +25°C

050 100

AMBIENT TEMPERATURE IN °C

-50

Dwg. GH-026

SWITCH POINT IN GAUSS

100

200

-100

-200

OPERATE POINT

RELEASE POINT

V = 12 V

150

300

-300

-25 25 75 125

10 15 20 25

SUPPLY VOLTAGE IN VOLTS

Dwg. GH-030

SUPPLY CURRENT IN mA

2.0

4.0

6.0

8.0

B ≥ B

B ≤ B

T = +25°C

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

SENSOR LOCATIONS

(±0.005” [0.13 mm] die placement)

Package Designators “LT”

132

. MH-008-4B

0.030"

0.76 mm

NOM

ACTIVE AREA DEPTH

0.050"

1.27 mm

0.090"

2.27 mm

Package Designator “U”

132

. MH-002-7B

0.015"

0.38 mm

NOM

BRANDED

SURFACE

ACTIVE AREA DEPTH

0.077"

1.96 mm

0.092"

2.33 mm

Package Designators “UA” and "UA-TL"

132

. MH-011-4B

0.018"

0.46 mm

NOM

BRANDED

SURFACE

ACTIVE AREA DEPTH

0.083"

2.10 mm

0.060"

1.51 mm

The simplest form of magnet that will operate these devices is a ring

magnet, as shown below. Other methods of operation are possible.

Dwg. A-11,899

OPERATION

In operation, the output transistor is OFF until the strength of the mag-

netic field perpendicular to the surface of the chip exceeds the threshold or

operate point (BOP). When the field strength exceeds BOP, the output transis-

tor switches ON and is capable of sinking 25 mA of current.

The output transistor switches OFF when magnetic field reversal results

in a magnetic flux density below the OFF threshold (BRP). This is illustrated

in the transfer characteristics graph (A3187* shown).

Note that the device latches; that is, a south pole of sufficient strength

will turn the device ON. Removal of the south pole will leave the device ON.

The presence of a north pole of sufficient strength is required to turn the

device OFF.

APPLICATIONS INFORMATION

Extensive applications information on magnets and Hall-effect sensors is

also available in the Allegro Integrated and Discrete Semiconductors Data

Book or Application Note 27701.

30 V

MAX

0+B

OUTPUT VOLTAGE IN VOLTS

FLUX DENSITY

Dwg. GH-034-4

-B

OUT(SAT)

Although sensor location is accurate to three

sigma for a particular design, product improve-

ments may result in small changes to sensor

location.

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

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. Minimum lead length was 0.500" (12.70 mm). If existing product to the original specifications is not acceptable,

contact sales office before ordering.

PACKAGE DESIGNATOR ‘U’

Dimensions in Inches

(controlling dimensions)

Dimensions in Millimeters

(for reference only)

Dwg. MH-003D in

0.063

0.059

0.018

0.015

0.016

0.050

1 2 3

0.100

45°

SEE NOTE

0.183

0.178

0.181

0.176

0.600

0.560

0.086

MAX

Dwg. MH-003D mm

1.60

1.50

0.46

0.38

0.41

1.27

1 2 3

2.54

45°

SEE NOTE

4.65

4.52

4.60

4.47

15.24

14.23

2.18

MAX

Devices in the ‘U’ package are

NOT RECOMMENDED FOR NEW DESIGN

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

Surface-Mount Lead Form (Suffix ‘-TL’)

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.

Dimensions in Inches

(controlling dimensions)

Dimensions in Millimeters

(for reference only)

PACKAGE DESIGNATOR ‘UA’

0.095

±0.005

0.020

MIN

FLAT

Dwg. MH-015 in

0.004

MAX

0.002

MAX

0°–8°

2.41

±0.13

0.51

MIN

FLAT

Dwg. MH-015 mm

0.10

MAX

0.051

MAX

0°–8°

Dwg. MH-014D mm

4.17

4.04

1.57

1.47

0.38

1.27

BSC

45°

16.26

15.24

0.41

2.16

MAX

45°

0.79

123

3.10

2.97

SEE NOTE

Dwg. MH-014D in

0.164

0.159

0.062

0.058

0.015

0.050

BSC

45°

0.640

0.600

0.016

0.085

MAX

45°

0.031

123

0.122

0.117

SEE NOTE

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

NOTE: Exact body and lead configuration at vendor’s option within limits shown.

PACKAGE DESIGNATOR ‘LT’

(SOT-89/TO-243AA)

Dimensions in Inches

(for reference only)

Dimensions in Millimeters

(controlling dimensions)

Dwg. MA-009-3 in

123

0.064

0.072

0.155

0.167

0.059

BSC

0.014

0.019

0.035

0.047

0.090

0.102

0.055

0.063 0.014

0.017

0.084

0.090

0.017

0.022

0.118

BSC

0.173

0.181

Dwg. MA-009-3 mm

123

4.40

4.60

1.62

1.83

3.94

4.25

1.50

BSC

0.36

0.48

0.89

1.20

2.29

2.60

1.40

1.60 0.35

0.44

2.13

2.29

0.44

0.56

3.00

BSC

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 design of its products.

The information included herein is believed to be accurate and

reliable. However, Allegro MicroSystems, Inc. assumes no responsi-

bility for its use; nor for any infringements of patents or other rights of

third parties which may result from its use.

3185

THRU

3189

HALL-EFFECT LATCHES

FOR HIGH-TEMPERATURE

OPERATION

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

HALL-EFFECT SENSORS SELECTION GUIDE

Partial Part Avail. Oper. Characteristics at TA = +25°C

Number Temp. BOP(max) BRP(min) Bhys(typ) Features Notes

HALL-EFFECT UNIPOLAR SWITCHES in order of BOP and Bhys

3240 E/L +50 +5.0 10 chopper stabilized 1

3210 E ±70 ±5.0 7.7 micropower, chopper stabilized

3361 E +120 +50 5.0* 2-wire, chopper stabilized

3362 E +120 +50 5.0* 2-wire, chopper stabilized

3161 E +160 +30 20 2-wire

3141 E/L +160 +10 55

3235 S +175 +25 15* output 1 2

-25 -175 15* output 2 2

5140 E +200 +50 55 300 mA output 1, 3

3142 E/L +230 +75 55

3143 E/L +340 +165 55

3144 E/L +350 +50 55

3122 E/L +400 +140 105

3123 E/L +440 +180 105

3121 E/L +450 +125 105

3150 J +40 to +850 – 20

programmable, chopper stabilized

HALL-EFFECT LATCHES & BIPOLAR SWITCHES† in order of BOP and Bhys

3260 E/L +30 -30 20 bipolar, chopper stabilized

3280 E/L +40 -40 45 chopper stabilized

3134 E/L +50 -50 27 bipolar switch

3133 K/L/S +75 -75 52 bipolar switch

3281 E/L +90 -90 100 chopper stabilized

3132 K/L/S +95 -95 52 bipolar switch

3187 E/L +150 -150 100*

3177 S +150 -150 200

3625 S +150 -150 200 900 mA outputs 1, 3, 5

3626 S +150 -150 200 400 mA outputs 1, 3, 5

3195 E/L +160 -160 220 1, 4

3197 L +160 -160 230 1

3175 S +170 -170 200

3188 E/L +180 -180 200*

3283 E/L +180 -180 300 chopper stabilized

3189 E/L +230 -230 100*

3275 S +250 -250 100* 5

3185 E/L +270 -270 340*

Operating Temperature Ranges:

S = -20°C to +85°C, E = -40°C to +85°C, J = -40°C to +115°C, K = -40°C to +125°C, L = -40°C to +150°C

Notes 1. Protected.

2. Output 1 switches on south pole, output 2 switches on north pole for 2-phase, bifilar-wound, unipolar-driven brushless dc

motor control.

3. Power driver output.

4. Active pull down.

5. Complementary outputs for 2-phase bifilar-wound, unipolar-driven brushless dc motor control.

* Minimum.

†Latches will not switch on removal of magnetic field; bipolar switches may switch on removal of field but require field reversal

for reliable operation over operating temperature range.