MELEXIS US1881L, US1881E Datasheet

US1881

CMOS Multi-Purpose Latch

Features and Benefits

• Chopper stabilized amplifier stage

• Optimized for BDC motor applications

• New miniature package / thin, high reliability package

• Operation down to 3.5V

• CMOS for optimum stability, quality and cost

Applications

• Solid state switch

• Brushless DC motor commutation

• Speed sensing

• Linear position sensing

• Angular position sensing

• Current sensing

Ordering Information

Part No. Temperature Suffix Package Temperature Range

US1881 E SO or UA -40oC to 85oC Commercial
US1881 L SO or UA -40oC to 150oC Automotive

*Contact factory or sales representative for legacy temperature options

Functional Diagram

SO Package
Pin 1 - V

DD

Pin 2 - Output
Pin 3 - GND

Output

V

DD

Voltage

Regulator

Chopper

GND

UA Package

Pin 1 - V

DD

Pin 2 - GND

Pin 3 - Output

Note: Static sensitive device; please observe ESD precautions. Re­verse VDD protection is not included. For reverse voltage protec­tion, a 100Ω resistor in series with VDD is recommended.

Description

The US1881 is the industry’s first Hall integrated
circuit in a SOT-23 package. The US1881 is a bi­polar Hall effect sensor IC fabricated from mixed
signal CMOS technology. It incorporates advanced
chopper stabilization techniques to provide accu­rate and stable magnetic switch points. There are
many applications for this HED in addition to those
listed above. The design, specifications and per­formance have been optimized for commutation
applications in 5V and 12V brushless DC motors.

The output transistor will be latched on (BOP) in the
presence of a sufficiently strong South pole mag­netic field facing the marked side of the package.
Similarly, the output will be latched off (BRP) in the
presence of a North field.

The SOT-23 device is reversed from the UA pack­age. The SOT-23 output transistor will be latched
on in the presence of a sufficiently strong North
pole magnetic field applied to the marked face.

US1881 CMOS Multi-Purpose Latch 3901001881 Rev. 5.2 7/23/01 Page 1

US1881

CMOS Multi-Purpose Latch

US1881 Electrical Specifications

DC Operating Parameters: TA = 25, VDD = 12VDC (unless otherwise specified).

Parameter Symbol Test Conditions Min Typ Max Units

Supply Voltage VDD Operating 3.5 24 V
Supply Current IDD B<BOP 1.5 2.5 4.0 mA
Saturation Voltage V
Output Leakage I

I

DS(on)

B<BRP, V

OFF

OUT

= 20 mA, B>BOP 0.4 0.5 V

= 20V 0.01 5.0 ì A

OUT

Output Rise Time tr VDD = 12V, RL = 1.1KÙ, CL = 20pf 0.04 ì s
Output Fall Time tf VDD = 12V, RL = 1.1KÙ, CL = 20pf 0.18 ì s

Parameter Symbol Test Conditions Min Typ Max Units

Operating Point BOP 1.0 5.0 9.0 mT
Release Point BRP -9.0 -5.0 -1.0 mT
Hysteresis B

Performance Graphs

Power Dissipation
versus
Temperature

5.5 10.0 12.0 mT

hys

Wave Soldering Parameters

500

400

300

200

All Devices

UA Package

R

=206oC/W

θJA

280

260

C)

o

240

220

All Devices

Solder Temperature (

100

Package Power Dissipation (mW)

0

SO Package

R

θ

JA

0-40 120 160 20040

=575oC/W

80

Temperature (oC)

US1881 CMOS Multi-Purpose Latch 3901001881 Rev. 5.2 7/23/01 Page 2

200

1050 20 25 30

Time in Wave Solder (Seconds)

15