Allegro A3240ELH, A3240LUA-TL, A3240LUA, A3240LLT, A3240LLH Datasheet

The A3240-- Hall-effect 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 short-circuit protected open-collector output to
sink up to 25 mA. A south pole of sufficient strength will turn the output
ON. An on-board regulator permits operation with supply voltages of

4.2 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
‘L–’ is -40°C to +150°C. Three package styles provide a magnetically
optimized package for most applications. Suffix ‘–LH’ is a modified
SOT-23 surface-mount package, ‘–LT’ is a miniature SOT-89/TO­243AA transistor package for surface-mount applications; while suffix
‘–UA’ is a three-lead ultra-mini-SIP for through-hole mounting.

Data Sheet

27621.20

FEATURES

■ Resistant to Physical Stress

■ Superior Temperature Stability

■ Output Short-Circuit Protection

■ Operation From Unregulated Supply

■ Reverse Battery Protection

■ Solid-State Reliability

■ Small Size

Suffix ‘–LT’ & ‘–UA’ Pinning

Pinning is shown viewed from branded side.

CHOPPER-STABILIZED, PRECISION

HALL-EFFECT SWITCH

3240

Supply Voltage, VCC........................ 26.5 V

Reverse Battery Voltage, V

RCC

.......... -30 V

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

Output OFF Voltage, V

OUT

................. 26 V

Continuous Output Current,

I

OUT

....................... Internally Limited

Reverse Output Current, I

OUT

........ -50 mA

Package Power Dissipation, PD. See Graph

Junction Temperature, TJ............... +170°C

Operating Temperature Range, T

A

Suffix ‘E–’ .................. -40°C to +85°C

Suffix ‘L–’ ................ -40°C to +150°C

Storage Temperature Range,

TS.............................. -65°C to +170°C

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

Always order by complete part number: the prefix ‘A’ + the basic four­digit part number + a suffix to indicate operating temperature range +
a suffix to indicate package style, e.g., A3240ELH .

Dwg. PH-003-2

1

SUPPLY

V

CC

GROUND

32

OUTPUT

X

PTCT

3240

CHOPPER-STABILIZED,
PRECISION
HALL-EFFECT SWITCH

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

2

FUNCTIONAL BLOCK DIAGRAM

Copyright © 2000 Allegro MicroSystems, Inc.

Suffix ‘–LH’ Pinning

Dwg. FH-020-1

GROUND

OUTPUT

<1Ω

X

DYNAMIC

OFFSET CANCELLATION

SUPPLY

CONTROL

CURRENT

LIMIT

REG.

SAMPLE

& HOLD

LOW-PASS

FILTER

TO ALL

SUBCIRCUITS

600

400

200

20 60 100 140

0

AMBIENT TEMPERATURE in °C

ALLOWABLE PACKAGE POWER DISSIPATION in MILLIWATTS

Dwg. GH-046-2C

Suffix "–UA"
R

θJA

= 206°C/W

40 80 120 180

700

500

300

100

160

Suffix "–LT"
R

θJA

= 258°C/W

Suffix "–LH"
R

θJA

= 248°C/W

Suffix "E–"

Suffix "L–"

Dwg. PH-003-4

SUPPLY

GROUND

OUTPUT

V

CC

X

PTCT

12

3

3240

CHOPPER-STABILIZED,

PRECISION

HALL-EFFECT SWITCH

www.allegromicro.com

3

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Supply Voltage Range V

CC

Operating, TJ < 170°C

1

4.2 – 24 V

Output Leakage Current I

OFF

V

OUT

= 24 V, B < B

RP

– – 10 µA

Output Saturation Voltage V

OUT(SAT)

I

OUT

= 20 mA, B > B

OP

– 185 500 mV

Output Current Limit I

OM

B > B

OP

30 – 60 mA

Power-On Time t

po

VCC > 4.2 V – – 50 µs

Chopping Frequency f

C

– 340 – kHz

Output Rise Time t

r

RL = 820 Ω, CL = 20 pF – 0.2 2.0 µs

Output Fall Time t

f

RL = 820 Ω, CL = 20 pF – 0.1 2.0 µs

Supply Current I

CC

B < BRP, VCC = 12 V – 3.0 6.0 mA

B > BOP, VCC = 12 V – 4.0 6.0 mA

Reverse Battery Current I

CC

V

RCC

= -30 V – – -5.0 mA

Zener Voltage VZ + V

D

ICC = 15 mA, TA = 25°C 283237 V

Zener Impedance zz + z

D

ICC = 15 mA, TA = 25°C–50–Ω

NOTES:1. Maximum voltage must be adjusted for power dissipation and junction temperature.

2. BOP = operate point (output turns on); BRP = release point (output turns off).

3. Typical Data is at TA = +25°C and VCC = 12 V and is for design information only.

ELECTRICAL CHARACTERISTICS over operating temperature range.

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Operate Point B

OP

– 35 50 G

Release Point B

RP

5.0 25 – G

Hysteresis B

hys

BOP - B

RP

– 10 – G

NOTE: 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.

3240

CHOPPER-STABILIZED,
PRECISION
HALL-EFFECT SWITCH

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

4

TYPICAL OPERATING CHARACTERISTICS

as a function of temperature

SUPPLY CURRENT

OUTPUT SATURATION VOLTAGE

SWITCH POINTS

0 50 100

AMBIENT TEMPERATURE IN °C

-50

Dwg. GH-026-5

SWITCH POINTS IN GAUSS

30

OPERATE POINT

150-25 25 75 125

40

50

0

10

20

VCC = 4.5 V
V

CC

= 24 V

RELEASE POINT

0 25 50 75 100

300

0

AMBIENT TEMPERATURE IN °C

200

100

-50

Dwg. GH-029-4

SATURATION VOLTAGE IN mV

150-25 125

IOUT = 20 mA

V

CC = 12 V

6.0

SUPPLY CURRENT IN mA

5.0

4.0

3.0

2.0
0 255075100

AMBIENT TEMPERATURE IN °C

-50

Dwg. GH-028-5

125-25 150

OUTPUT ON, B > B

OP

OUTPUT OFF, B < B

RP

VCC = 12 V