Infineon XENSIV TLI4971 - Communication Timing; Single Low;High PWM Transmission

Application Note 7 of 31 Rev. 1.30
2022-03-01
Current Sensor TLI4971
Programming Guide and User Manual
t
IFen
100µs 400µst=0
0"0" 1" 0"
A
OUT
V
sens
(3.3V)
GND
V
DD
V
Sens
GND
Low_state(1.3V)
High_state(1.6V)
High_state(1.6V)
Figure 5 Enabling SICI interface after device start up
2.3 Communication timing
As communication runs in both direction the GPIO of the external controller shall support tri state. After releasing
the A
OUT
back to V
Sens
, the 16-bit enter-interface-command with LSB first has to be send from the controller. Figure
5 shows the LSB and MSB of the enter-interface-command.
In the Figure 5, the green highlighted squares indicate the received bit while the blue highlighted squares indicate
the bits sent by the sensor.
2.3.1 Single low/high PWM transmission
The initial pulse length t
1
& t
2
in Figure 6 and Figure 7 determines the write sequence.
t
1_0
t
2_0
t
3
t
4
t
5
A
OUT
V
CC_IO
(hi-Z)
GND
1"
t
r,min
t
r,max
Figure 6 SICI duty cycle; sending logic '0' to the device; receiving logic '1' from the device
The read-out time t
4
is marked with a grey square. The timing of the read sequence t
4
is depending on the low
time t
1
and high time t
2
as described in Table 1.