TLE4998S3 Datasheet, PDF (36/39 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor

TLE4998S
SENT Output Definition (SAE J2716)
13.2 Unit Time Setup
The basic SENT protocol unit time granularity is defined as 3 µs. Every timing is a
multiple of this basic time unit. To achieve more flexibility, trimming of the unit time can
be used to:
• Allow a calibration trim within a timing error of less than 20% clock error (as given in
SAE standard)
• Allow a modification of the unit time for small speed adjustments
This enables a setup of different unit times, even if the internal RC oscillator varies by
±20%. Of course, timing values that are too low could clash with timing requirements of
the application and should therefore be avoided, but in principle it is possible to adjust
the timer unit for a more precise protocol timing.
Table 19 Predivider Setting
Parameter
Symbol Limit Values Unit Notes
Register size
Unit time
min. max.
Prediv
4
bit
t_UNIT
2.0 4.0
µs
Predivider¹⁾
Clk_UNIT=8MHz²⁾
1) _{Useable predivider range is decimal 7 to 15. Prediv < 7 is internally kept at 7. Prediv default is decimal = 11 for}
3 µs nominal unit time
2) _{RC oscillator frequency variation +/- 20%}
The nominal unit time is calculated by:
t_UNIT = (Prediv × 2 + 2) / Clk_UNIT
Clk_UNIT = 8MHz ±20%
Data Sheet
36
V 1.0, 2008-07