A3980 Allegro MicroSystems, Inc., A3980 Datasheet - Page 15

• Manufacturer Part Number: A3980
• Description: Automotive DMOS Microstepping Driver with Translator
• Manufacturer: Allegro MicroSystems, Inc.

Current Sensing. To minimize inaccuracies caused by
ground-trace IR drops in sensing the output current level,
the current-sense resistors (R
independent ground return to the star ground point. This path
should be as short as possible. For low-value sense resistors,
the IR drops in the printed circuit board sense resistor traces
can be signifi cant and should be taken into account. The use
of sockets should be avoided as they can introduce variation
in R
The recommended value of the sense resistor, R
given by
up to a maximum of 1 Ω for I
R
in the following table.
S
should be 1 Ω, and V
S
due to their contact resistance.
I
MAX
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
(A)
R
S
REF
= 0.5 / I
R
1.00
1.00
1.00
1.00
1.00
0.83
0.71
0.63
0.56
0.50
S
reduced accordingly, as shown
S1
(Ω)
Recommended
Automotive DMOS Microstepping Driver with Translator
TripMAX
and R
TripMAX
of 0.5 A. Below 0.5 A,
S2
) should have an
V
REF
0.8
1.6
2.4
3.2
4.0
4.0
4.0
4.0
4.0
4.0
(V)
S
(Ω), is
www.allegromicro.com
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
A3980
15