Allegro A3054SU-30, A3054SU-29, A3054SU-28, A3054SU-27, A3054SU-26 Datasheet

3054

MULTIPLEXED
TWO-WIRE
HALL-EFFECT SENSOR ICs

The A3054KU and A3054SU Hall-effect sensors are digital mag­netic sensing ICs 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.

Each device consists of high-resolution bipolar Hall-effect switch­ing circuitry, the output of which drives high-density CMOS logic
stages. The logic stages decode the address pulse and enable a
response at the appropriate address. The combination of magnetic­field or switch-status sensing, low-noise amplification of the Hall­transducer output, and high-density decoding and control logic is made
possible by the development of a new sensor DABiC™ (digital analog
bipolar CMOS) fabrication technology. The A3054SU is an improved
replacement for the original UGN3055U.

These unique magnetic sensing ICs are available in two tempera­ture ranges; the A3054SU operates within specifications between

-20°C and +85°C, while the A3054KU is rated for operation between

-40°C and +125°C. Alternative magnetic and temperature specifica­tions are available on special order. Both versions are supplied in

0.060" (1.54 mm) thick, three-pin plastic SIPs. Each device is clearly
marked with a two-digit device address (XX).

3054

MULTIPLEXED TWO-WIRE

HALL-EFFECT SENSOR ICs

FEATURES

■ Complete Multiplexed Hall-Effect ICs 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 DABiC Technology Favors

Battery-Powered and Mobile Applications

■ Ideal for Automotive, Consumer, and Industrial Applications

Always order by complete part number:

Part Number Operating Temperature Range

A3054KU-XX -40°C to +125°C
A3054SU-XX -20°C to +85°C
where XX = address (01, 02, … 29, 30).

Pinning is shown viewed from branded side.

ABSOLUTE MAXIMUM RATINGS

at T

A

= +25°C

Supply Voltage, V

BUS

. . . . . . . . . . . . . . 18 V

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

Operating Temperature Range, T

A

A3054KU . . . . . . . . . . . -40°C to +125°C

A3054SU . . . . . . . . . . . . -20°C to +85°C

Storage Temperature Range,

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

Package Power Dissipation,

PD. . . . . . . . . . . . . . . . . . . . . . . 635 mW

Data Sheet

27680.1

Dwg. PH-005

1

BUS

GROUND

32

SWITCH IN

X

LOGIC

3054

MULTIPLEXED
TWO-WIRE
HALL-EFFECT SENSOR ICs

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

Limits

Characteristic Symbol Test Conditions Min Typ Max Units

Power Supply Voltage V

BUS

——15 V

Signal Current I

S

DUT Addressed, B > 300 G 12 15 20 mA

Quiescent Current I

QL

V

BUS

= 6 V — 1.5 2.5 mA

I

QH

V

BUS

= 9 V — 1.4 2.5 mA

∆I

Q

I

QL

– I

QH

— 100 300 µA
Address Range Addr Factory Specified 1 — 30 —
Clock Thresholds V

CLH

LOW to HIGH — — 8.5 V

V

CHL

HIGH to LOW 6.5 — — V

V

CHYS

Hysteresis — 0.8 — V

Max. Clock Frequency* f

CLK

50% Duty Cycle 2.5 — — kHz

Address LOW Voltage V

L

V

RST

6.0 V

CHL

V

Address HIGH Voltage V

H

V

CLH

9.0 V

BUS

V

Reset Voltage V

RST

2.5 3.5 5.5 V

Propagation Delay* t

plh

LOW to HIGH 10 20 30 µs

t

phl

HIGH to LOW — 5.0 10 µs

Pin 3-2 Resistance R

SWH

DUT Addressed, B < 5 G — 50 — kΩ

R

SWL

DUT Addressed, B > 300 G — 200 — Ω

Pin 3-2 Output Voltage V

SWH

DUT Addressed, B < 5 G — 3.9 — V

V

SWL

DUT Addressed, B> 300 G — 30 — mV

MAGNETIC CHARACTERISTICS over operating temperature range.

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Magnetic Threshold† B

OP

Turn-On 50 150 300 G

B

RP

Turn-Off 5.0 100 295 G

Hysteresis B

HYS

B

OP

– B

RP

5.0 50 — G

ELECTRICAL CHARACTERISTICS over operating temperature range.

Typical Data is at TA = +25°C and is for design information only.
*This parameter, although warranteed, is not production tested.
†Alternative magnetic switch point specifications are available on special order. Please contact the factory.

W
Copyright © 1995 Allegro MicroSystems, Inc.

3054

MULTIPLEXED
TWO-WIRE
HALL-EFFECT SENSOR ICs

FUNCTIONAL BLOCK DIAGRAMSENSOR LOCATION

(±0.005” [0.13 mm] die placement)

CLOCK

Dwg. FH-009

BUS

SWITCH IN

(OPTIONAL)

GROUND

CMOS LOGIC

REG

COMP COMP

RESET

1

3

2

1 32

Dwg. MH-002-10A

0.015"

0.38 mm
NOM

BRANDED
SURFACE

ACTIVE AREA DEPTH

0.073"

1.85 mm

A

0.090"

2.29 mm

DEFINITION OF TERMS

Sensor Address

Each bus sensor has a factory-specified predefined
address. At present, allowable sensor addresses are
integers from 01 to 30.

LOW-to-HlGH Clock Threshold (V

CLH

)

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 that
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
on-chip comparator that monitors the supply voltage,
V

BUS

.

Bus HIGH Voltage (VH)

Bus HIGH voltage during addressing. Voltage should

be greater than V

CLH

.

Address LOW Voltage (VL)

Bus LOW voltage during addressing. Voltage should

be greater than V

RST

and less than V

CHL

.

Bus Reset Voltage (V

RST

)

Voltage level while resetting sensors.

Sensor Quiescent Current Drain (IQ)

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

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 the 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 is called the signal
current.

Sensor Address Response Current (IS)

Sensor current during the

diagnostic

and the

signal

responses of the bus sensor. This is accomplished by
enabling an internal constant-current source.

3054

MULTIPLEXED
TWO-WIRE
HALL-EFFECT SENSOR ICs

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

A device may be addressed by changing the supply
voltage as shown in Figure 1. A preferred addressing
protocol is as follows: the bus supply voltage is brought
low (<2.5 V) so that all devices on the bus are reset. The
voltage is then raised to the address LOW voltage (VL) and
the bus quiescent current is measured. The bus is then
toggled between VL and VH (address HIGH voltage), with
each positive transition representing an increment in the
bus address. After each voltage transition, the bus current
may be monitored to check for diagnostic and signal
responses from sensor ICs.

Sensor Addressing

When a sensor detects a bus address equal to its
factory-programmed address, it responds with an increase
in its supply current drain ( IS) during the next HIGH portion

ADDRESSING PROTOCOL

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 been
switched ON. When a device is deactivated by changing
the bus address, all magnetic memory is lost.

Magnetic Hysteresis (B

HYS

)

Difference between the BOP and BRP magnetic field
thresholds.

FIGURE 1

BUS TIMING

SENSOR 03 — DIAGNOSTIC

AND SIGNAL CURRENTS

DIAGNOSTIC
ADDRESS 01

DIAGNOSTIC
ADDRESS 02

DIAGNOSTIC
ADDRESS 04

DIAGNOSTIC

ADDRESS

n

RESET

DIAGNOSTIC
ADDRESS 01

SENSOR 02 —
DIAGNOSTIC CURRENT

DIAGNOSTIC
ADDRESS 03

SENSOR 01

NOT PRESENT

V

H

V

L

V

RST

0

I

S

I

QL

I

QH

0

I

S

0

I

S

n • I

QL

n • I

QH

0

t

phl

t

plh

V

CLH

V

CHL

Dwg. WH-005

BUS

VOLTAGE

SENSOR 02

CURRENT

WITH NO

MAGNETIC

FIELD

SENSOR 03

CURRENT

WITH

MAGNETIC

FIELD

TOTAL

BUS CURRENT

WITH

MAGNETIC

FIELD AT

SENSOR 03

RESET

I

QL

I

QH

SENSOR 01

NOT PRESENT