Allegro A3150JUA, A3150JLT Datasheet

Data Sheet

27621.40

3150

PROGRAMMABLE, CHOPPER-

STABILIZED, HALL-EFFECT SWITCH

The A3150JLT and A3150JUA programmable switches provide tooth/valley recognition in large gear-tooth sensing applications. Each sensor consists of a single element, chopper-stabilized Hall-effect IC

PTCT

that can be programmed to the desired magnetic switch point, optimizing sensor airgap and timing accuracy performance after final packaging. The small package can be easily assembled and used in conjunction with a wide variety of gear/target shapes and sizes. The two devices differ only in package style.

The sensing technology used for this sensor is Hall-effect based. The sensor incorporates a single-element Hall IC that switches in response to magnetic signals created by a ferrous target. The programmability of the circuit eliminates magnet and system offsets such as those caused by tilt yet provides zero-speed detection capabilities without the associated running jitter inherent in classical digital solutions.

A proprietary dynamic offset cancelation technique, with an

SUPPLY

GROUND

Dwg. PH-003-2

PRELIMINARY INFORMATION

(subject to change without notice)

April 12, 1999

ABSOLUTE MAXIMUM RATINGS

at T

= 25°C

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

Reverse Supply Voltage, V

Overvoltage Supply Current, ICC..... 100 mA

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

DISCONTINUED PRODUCT

Output Current, I Output OFF Voltage, V Reverse Output Current, I Operating Temperature Range,

TA............................... -40°C to +115°C

Storage Temperature, TS................... +170°C

— FOR REFERENCE ONLY.

..... Internally Limited

OUT

Use A3250 for new design

OUTPUT

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

RCC

................. 26.5 V

......... -50 mA

ROUT

internal high-frequency clock, reduces the residual offset voltage, which is normally caused by device overmolding, temperature dependancies, and thermal stress. This technique produces devices that have an extremely stable quiescent output voltage, are immune to mechanical stress, and have precise recoverability after temperature cycling. Many problems normally associated with low-level analog signals are minimized by having the Hall element and amplifier in a single chip. Output precision is obtained by internal gain adjustments during the manufacturing process and operate-point programming in the user’s application.

This sensor system is ideal for use in gathering speed, position, and timing information using gear-tooth-based configurations. The A3150JLT/JUA are particularly suited to those applications that require accurate duty cycle control or accurate edge detection. The lower vibration sensitivity also makes these devices extremely useful for transmission speed sensing.

Continued next page

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., A3150JLT .

3150

PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH

FUNCTIONAL BLOCK DIAGRAM

PROGRAM

LOGIC

REG.

SUPPLY

& HOLD

DYNAMIC

OFFSET CANCELLATION

SAMPLE

Two 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; while suffix ‘–UA’ is a three-lead ultra-mini-SIP for through-hole mounting.

FEATURES AND BENEFITS

FILTER

LOW-PASS

OFFSET ADJUST

POWER-UP

CONTROL

CURRENT

LIMIT

<1Ω

OUTPUT

GROUND

Dwg. FH-020-3

■ Chopper Stabilized for

Extremely Low Switch-Point Drift and

Immunity to Mechanical Stress

■ Externally Programmed Switch Point

■ On-Chip Supply-Transient Protection

■ Output Short-Circuit Protection

■ Single-Chip Sensing IC for High Reliability

■ Small Mechanical Size

■ <50 µs Power-On Time

■ Wide Operating Voltage Range

■ Defined Power-On State

3150

PROGRAMMABLE, CHOPPER-

STABILIZED, PRECISION,

HALL-EFFECT SWITCH

ELECTRICAL CHARACTERISTICS over operating voltage and temperature range (unless otherwise noted).

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Supply Voltage V

Power-On State POS After programming, V

Low Output Voltage V

Output Current Limit I

Output Leakage Current I

Supply Current I

OUT(SAT)

OUTM

OFF

Operating, T

= 20 mA – 175 400 mV

OUT

= 12 V 65 80 95 mA

OUT

= 24 V – 0.2 10 µA

OUT

< 165°C 4.25 – 26 V

= 0 → 5 V HIGH HIGH HIGH –

Before programming, output OFF – 4.0 7.0 mA

Before programming, output ON – 5.0 8.0 mA

Reverse Supply Current I

Power-On Delay t

Output Rise Time t

Output Fall Time t

Clock Frequency f

Zener Voltage V

Zener Impedance z

RCC

= -30 V – – -5.0 mA

RCC

> 5 V – 20 50 µs

= 820 Ω, C

= 100 µA, TA = 25°C2732–V

IZT = 10 mA, T

= 20 pF – 200 – ns

= 20 pF – 100 – ns

= 25°C – 50 100 Ω

NOTE: Typical data is at VCC = 5 V and TA = +25°C and is for design information only.

– 340 – kHz

MAGNETIC CHARACTERISTICS over operating supply voltage and temperature ranges.

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Operate Point B

Hysteresis B

∆B

hys

NOTE: Typical data is at VCC = 5 V and TA = +25°C and is for design information only.

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Programmable offset range 500 670 850 G

Initial (before programming) 0 20 40 G

Resolution 8.0 11 14 G

VCC = 14 V, after programming, B

≈ 500 G

-35 8.0 +35 G

5.0 20 35 G

3150

PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH

TYPICAL ELECTRICAL CHARACTERISTICS

5.0

4.0

3.0

2.0

SUPPLY CURRENT IN mA

1.0

-50

B > B

0 25 50 75

AMBIENT TEMPERATURE IN °C

300

T = +25°C

V = 5 V

100

125-25

150

Dwg. GH-053-2

B < B

8.0

6.0

4.0

SUPPLY CURRENT IN mA

2.0

SUPPLY VOLTAGE IN VOLTS

B > B

B < B

10 15 20 25

Dwg. GH-041-2

I = 20 mA

OUT

V = 4.5–24 V

200

100

SATURATION VOLTAGE IN mV

-50

-25

0 25 50 75

AMBIENT TEMPERATURE IN °C

100

150

125

Dwg. GH-040-4

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