ES5338.1 Carrier Board for Wheel Speed Sensor Simulation - User’s Guide
31
ETAS
Simulated Sensor Signals
.
Fig. 3-2
Output signals of a sensor of type "DF11i"
"N" and "S" represent adjacent segments of the pick-up wheel.
3.3.3
VDA
The wheel speed sensor signals of type VDA consist of one speed pulse followed
by 9 data bits for each segment of the pick-up wheel. They contain information
about the following parameters:
• Wheel speed
• Tooth voids
• Travel direction
• Standstill detection
• Air gap reserve error detection
• Installation position error detection
Very low field strength
(Air gap limit error)
Backward drive
normal field strength
Forward drive
normal field strength
Backward drive
low field strength
(mounting position error)
Forward drive
low field strength
(mounting position error)
T
0
2T
0
4T
0
8T
0
16T
0
32T
0
737 ms
T
0
= 45 µs
No field or vehicle
stopped for > 737 ms
No Field or Vehicle Stopped
7 mA
14 mA
7 mA
14 mA
Vehicle Movement
7 mA
14 mA
7 mA
14 mA
7 mA
14 mA
7 mA
14 mA
N
S