TLE4998C3 Datasheet, PDF (39/44 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor

TLE4998C
SPC Output Definition
13.4
Synchronous Transmission
In the “synchronous” mode, the sensor (slave) starts to transfer a complete data frame
only after a low pulse is forced by the master on the OUT pin. This means that the data
line is bidirectional - an open drain output of the microcontroller (master) sends the
trigger pulse. The sensor then initiates a sync pulse and starts to calculate the new
output data value. After the synchronization period, the data follows in form of a standard
SENT frame, starting with the status, data and CRC nibbles. At the end, an end pulse
allows the CRC nibble decoding and indicates that the data line is idle again. The timing
diagram in Figure 13 visualizes a synchronous transmission.
Table 25 Master Pulse Timing Requirements for Synchronous Mode
Parameter
Symbol
Limit Values Unit¹⁾ Notes
min. typ. max.
Master low time
t_mlow
1.5 2.75 4
UT
1) _{UT = Programmed nominal SPC unit time}
Sensor
VDD
OUT
GND
CPU
Capcom-Unit
Outpin (OD)
Figure 15 Bidirectional Communication in Synchronous Mode
13.5
Synchronous Transmission Including Range Selection
The low time duration of the master can be used to select the magnetic range of the
sensor in SPC dynamic range selection mode.
Table 26 Master Pulse Timing Requirements for Dynamic Range Mode
Parameter
Master low time
Symbol
t_mlow
Limit Values Unit¹⁾ Notes
min. typ. max.
1.5 3.25 5
UT Range = 200mT (R=0)
9
12 15 UT Range = 100mT (R=1)
24 31.5 39 UT Range = 50mT (R=3)
1) _{UT = Programmed nominal SPC unit time}
Data Sheet
39
Rev 1.0, 2008-12