Allegro UGN3055U Datasheet

3055

MULTIPLEXED
TWO-WIRE HALL EFFECT
SENSOR IC

3055

Data Sheet

27680

DISCONTINUED PRODUCT

Shown for Reference Only

X

LOGIC

1

BUS

32

GROUND

SWITCH IN

Dwg. PH-005

MULTIPLEXED TWO-WIRE

HALL-EFFECT SENSOR ICs

The UGN3055U Hall-effect sensor is a digital magnetic sensing IC
capable of communicating over a two-wire power/signal bus. Using a
sequential addressing scheme, the device responds to a signal on the
bus and returns the diagnostic status of the IC, as well as the status of
each monitored external magnetic field. As many as 30 sensors can
function on the same two-wire bus. This IC is ideal for multiple sensor
applications where minimizing the wiring harness size is desirable or
essential.

The device consists of high-resolution bipolar Hall-effect switching
circuitry, the output of which drives high-density CMOS logic stages.
These logic stages decode the address pulse and enable a response
at the appropriate address. The combination of magnetic-field or
switch-status sensing, low-noise amplification of the Hall-transducer
output, and high-density decoding and control logic is made possible
by the development of a new sensor BiMOS fabrication technology.

This unique magnetic sensing IC operates within specifications
between -20°C and +85°C. Alternate magnetic and temperature
specifications are available upon request. It is supplied in a 60 mil
(1.54 mm) thick, three-pin plastic SIP. Each package is clearly marked
with a two-digit decimal device address (xx).

Pinning is shown viewed from branded side.

ABSOLUTE MAXIMUM RATINGS

at T

= +25°C

A

Supply Voltage, V

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

Operating Temperature Range,

T

.......................... -20°C to +85°C

A

Storage Temperature Range,

.............................. -55°C to +150°C

T

S

Package Power Dissipation,

P

.................................... 750 mW

D

........................... 24 V

BUS

FEATURES

■ Complete Multiplexed Hall-Effect IC with

Simple Sequential Addressing Protocol

■ Allows Power and Communication Over a

Two-Wire Bus (Supply/Signal and Ground)

■ Up to 30 Hall-Effect Sensors Can Share a Bus

■ Sensor Diagnostic Capabilities

■ Magnetic-Field or Switch-Status Sensing

■ Low Power of BiMOS Technology Favors

Battery-Powered and Mobile Applications

■ Ideal for Automotive, Consumer, and Industrial Applications

Always order by complete part number: UGN3055U .

3055

MULTIPLEXED
TWO-WIRE HALL EFFECT
SENSOR IC

OPERATIONAL CHARACTERISTIC over operating temperature range.

Electrical Limits
Characteristics

Power Supply Voltage V
Signal Current I
Quiescent Current V

= 6 V I

BUS

= 9 V I

V

BUS

I

QH–IQL

Address Range Addr 1 — 30 —
Clock Thresholds LOW to HIGH V

HIGH to LOW V

Hysteresis V
Clock Period t
Address LOW Voltage V
Address HIGH Voltage V
Power-On Reset Voltage V
Settling Time V

= 9 V t

BUS

= 6 V t

V

BUS

Propagation Delay LOW to HIGH t

HIGH to LOW t

Pin 3 Input Resistance No Magnetic Field (V

Mag. Field Present (V

= HIGH) R

OUT

= LOW) R

OUT

Magnetic Characteristics

Magnetic Thresholds *Turn-On B

Turn-Off B

Hysteresis (B

*Alternate magnetic switch point specifications are available on request. Please contact the factory.

)B

OP–BRP

Symbol Min. Typ. Max. Units

BUS

S

QH

QL

I

Q

CLH

CHL

CHYS

CLK

L

H

RST

h

l

plh

phl

OUTH

OUTL

OP

RP

HYS

——15V
12 15 20 mA
— — 2.5 mA
— — 2.5 mA
— — 300 µA

— — 8.5 V

6.5 — — V
— 0.8 — V

0.1 1.0 — ms

V

RST

V

CLH

6V
9V

CHL

BUS

2.5 3.5 5.5 V

100 — — µs
100 — — µs

10 — — µs
——10µs
40 — 75 kΩ
——50Ω

50 150 300 G

-25 100 300 G

05075G

V
V

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

W
Copyright © 1988, 1991, Allegro MicroSystems, Inc.

3055

A

MULTIPLEXED
TWO-WIRE HALL EFFECT
SENSOR IC

(±0.005” [0.13 mm] die placement)

ACTIVE AREA DEPTH

0.015"

0.38 mm

NOM

0.071"

1.80 mm

0.084"

2.13 mm

FUNCTIONAL BLOCK DIAGRAMSENSOR LOCATION

1

BUS

REG

COMP COMP

CLOCK

CMOS LOGIC

RESET

SWITCH IN

3

(OPTIONAL)

BRANDED
SURFACE

1 32

Dwg. MH-002A

DEFINITION OF TERMS

Sensor Address

Each bus sensor has a factory-specified predefined
address. At present, allowable sensor addresses are
integers from 1 to 30.

LOW-to-HlGH Clock Threshold (V

Minimum voltage required during the positive-going
transition to increment the bus address and trigger a
diagnostic response from the bus sensors. This is also
the maximum threshold of the on-chip comparator, which
monitors the supply voltage, V

BUS

HlGH-to-LOW Threshold (VHL)

Maximum voltage required during the negative-going
transition to trigger a

signal

current response from the bus
sensors. This is also the maximum threshold of the on­chip comparator, which monitors the supply voltage, V

Bus HIGH Voltage (VH)

Bus HIGH voltage required for addressing. Voltage
should be greater than V

CLH

.

Address LOW Voltage (VL)

Bus LOW Voltage required for addressing. Voltage
should be greater than V

Bus Reset Voltage (V

and less than V

RST

)

RST

Voltage level required to reset individual sensors.

Sensor Quiescent Current Drain (IQ)

The current drain of bus sensors when active but not
addressed. IQH is the maximum quiescent current drain
when the sensor is not addressed and is at VH. IQL is the
maximum quiescent current drain when the sensor is not
addressed and is at VL.

)

CLH

.

BUS.

.

CHL

GROUND

2

Dwg. FH-009

Diagnostic Phase

Period on the bus when the address voltage is at VH.
During this period, a correctly addressed sensor responds
by increasing its current drain on the bus. This response
from the sensor is called the diagnostic response and
the bus current

increase

is called the diagnostic current.

Signal Phase

Period on the bus when the address voltage is at VL. During
this period, a correctly addressed sensor that detects a
magnetic field greater than magnetic Operate Point, BOP,
responds by maintaining a current drain of IS on the bus.
This response from the sensor is called the signal response
and the bus current

increase

is called the signal current.

Sensor Address Response Current (IS)

Current returned by the bus sensors during the
the

signal

responses of the bus sensors. This is accomplished

diagnostic

and

by enabling the constant current source (CCS).

Magnetic Operate Point (BOP)

Minimum magnetic field required to switch ON the Hall
amplifier and switching circuitry of the addressed sensor.
This circuitry is only active when the sensor is addressed.

Magnetic Release Point (BRP)

Magnetic field required to switch OFF the Hall amplifier
and switching circuitry after the output has switched ON.
This is due to magnetic memory in the switching circuitry.
However, when a device is deactivated by changing the
current bus address, all magnetic memory is lost.

Magnetic Hysteresis (B

HYS

)

Difference between the BOP and BRP magnetic field thresh­olds.