tle4942 Infineon Technologies Corporation, tle4942 Datasheet - Page 17

• Manufacturer Part Number: tle4942
• Description: Differential Two-wire Hall Effect Sensor-ic For Wheel Speed Applications With Direction Detection
• Manufacturer: Infineon Technologies Corporation

TLE4942-1
TLE4942-1C
I
Xn
Xn+1
Xn+2
I
HIGH
I
LOW
t
1
T
t
t
Duty =
/ T x 100%
1
AET03195
Figure 7
Definition of Duty Cycle
PWM Current Interface
Between each magnetic transition and the rising edge of the corresponding output pulse
t
the output current is Low for
in order to allow reliable internal conveyance.
pre-low
Following the signal pulse (current is High) is output.
If the magnetic differential field exceeds ∆
B
, the output pulse lengths are 90 µs or
EL
180 µs respectively, depending on the direction of rotation.
When the magnitude of the magnetic differential field is below ∆
B
, the output pulse
EL
lengths are 360 µs and 720 µs respectively, depending on left or right rotation. Due to
decreasing cycle times at higher frequencies, these longer pulses are only output up to
frequencies of approximately 117 Hz. For higher frequencies and differential magnetic
fields below ∆
B
, the output pulse lengths are 90 µs or 180 µs respectively.
EL
If the magnitude of the magnetic differential field is below ∆
B
, the output pulse
Warning
length is 45 µs. The warning output is dominant, this means that close to the limit airgap
the direction and the assembly position information are disabled.
For magnitudes of the magnetic differential field below ∆
B
, signal is lost.
Limit
In case no magnetic differential signal is detected for a time longer than the stand still
T
period
, the stop pulse is output. Typically with the first output stop pulse, the circuitry
Stop
reverts to the uncalibrated mode.
Data Sheet
17
V 3. 1, 2005-02