Page 11/18

LEM reserves the right to carry out modifications on its transducers, in order to improve them, without prior notice.

www.lem.com

100727/10

FHS 40-P/SP600

0 - 100A

Application information

Single track on PCB

The main pratical configurations will now be reviewed and their main features highlighted.

The use of Minisens to measure a current flowing in a track provides the following advanges:

Isolation is guaranteed by PCB design. If the primary track is placed on the opposite (bottom) side of the PCB,

●

the isolation can be very high

stable and reproducible sensitivity

●

inexpensive

●

large input currents (up to about 100 A).

●

Figure 10: Principle of Minisens used to measure current in a PCB track

Figure 11: Sensitivity versus track width and versus distance between the track and the Minisens sensing

elements

Primary Conductor (Track)

PCB

B

Primary Conductor

(Track)

PCB

B

B

PCB

1

Ip

Sensitivity function of track to magnetic sensor distance

(track 70 microns thick)

0

20

40

60

80

100

120

1

1.5

2

2.5

3

3.5

track axis to sensor distance (mm)

1 mm wide track

2 mm wide track

3 mm wide track

1.235

nominal distance for

a top side track

2.905

nominal distance for a

bottom side track with

1.6 mm PCB