11/16

TSZ02201-0M2M0F414010-1-2

© 2014 ROHM Co., Ltd. All rights reserved.

11.Aug.2014 Rev.001

www.rohm.com

TSZ22111 • 15 • 001

BU52077GWZ

Slide-by Position Sensing

Figure 20 depicts the slide-by configuration employed for position sensing. Note that when the gap (d) between the magnet

and the Hall IC is narrowed, the reverse magnetic field generated by the magnet can cause the IC to malfunction. As seen

in Figure 21, the magnetic field runs in opposite directions at Point A and Point B. Since the dual output omnipolar detection

Hall IC can detect the S-pole at Point A and the N-pole at Point B, the sensor can switch the output ON as the magnet

slides by in the process of position detection. Figure 22 plots magnetic flux density during the magnet slide-by. Although a

reverse magnetic field was generated in the process, the magnetic flux density decreases compared with the center of the

magnet. This demonstrates that slightly widening the gap (d) between the magnet and Hall IC reduces the reverse

magnetic field and prevents malfunctions.

Position of the Hall Element

(Reference)

Footprint Dimensions

(Optimize footprint dimensions to the board design and soldering condition)

I/O Equivalence Circuit

Symbol

Reference

value

e

0.40

b3

φ

0.20

SD

0.20

SE

0.20

-10.0

-5.0

0.0

5.0

10.0

0

2

4

6

8

10

Horizontal Distance from the Magnet

[mm]

The Hall ICs output pins are configured for CMOS (inverter)

output removing the need for external resistance and allow

direct connection to the host. Removing the need for external

resistors allows for reduction of the current that would

otherwise flow to the external resistor during magnetic field

detection thereby supporting an overall lower current

(micropower) operation.

GND

VDD

OUT1, OUT2

Figure 23

L

Figure 20

d

Magnet

Hall IC

Slide

Reverse

Figure 22. Magnetic Flux Density vs Horizontal

Distance from the Magnet

Figure 21

B

S

A

N

Flux

Flux

(UNIT: mm)

0.40

0.40

0.25

UCSP35L1

e

SD

b3

UCSP35L1

(UNIT：mm)