Infineon XENSIV TLI4971 - Semi-differential Mode

Application Note 25 of 31 Rev. 1.30
2022-03-01
Current Sensor TLI4971
Programming Guide and User Manual
µC
TLI4971
V
3V3
VDD
OCD1
OCD2
VREF
AOUT
GND
V
REF
ADC
IN+
IN-
V
REF
GPIO
GPIO
V
3V3
V
3V3
IN+
IN-
Figure 18 TLI4971 (fully-differential mode) connected to differential ADC
5.3 Semi-differential Mode
In Semi-Differential Output Mode, the sensor is using a chip-internal reference voltage. This reference voltage is
then provided on the VREF. Therefore, the reference voltage can be monitored by the microcontroller and/or
used for other devices as a reference voltage (cascade setup). The current-dependent output signal is provided
as single-ended signal on AOUT.
The Quiescent Voltage will be set to a value in the middle of the voltage range or at 1.5V (V
OQbid
) to measure
bidirectional current values, whereas when the direction of the current is already known by the application, the
quiescent voltage can be set to a lower value (V
OQuni
) in order to better exploit the full voltage range.
A
OUT
[V]
V
REF
[V]
V
REF
Internal
refrence
Voltage
t
t
I[A]
0A
Sensor Input (current to measure) Sensor Output Voltage
t
Figure 19 Sensor output signal dependent on input signal waveform in semi-differential mode
ADC
V
REF
µC
TLI4971
V
3V3
VDD
OCD1
OCD2
VREF
AOUT
GND
GPIO
GPIO
V
3V3
V
3V3
Figure 20 TLI4971 in semi-differential mode