ST25R3911B Datasheet, PDF (99/129 Pages) STMicroelectronics – Automatic antenna tuning system providing tuning of antenna LC tank

ST25R3911B
1.3.33
A/D Converter Output Register
Address: 20h
Type: R
Table 58. A/D Converter Output Register⁽¹⁾
Bit
Name Default
Function
Comments
7
ad7
-
6
ad6
-
5
ad5
-
4
ad4
3
ad3
-
Displays result of last A/D
-
conversion.
-
2
ad2
-
1
ad1
-
0
ad0
-
1. At power-up and after Set Default command, see Table 9, content of this register is set to 0.
1.3.34
Antenna Calibration Control Register
Address: 21h
Type: RW
Table 59. Antenna Calibration Control Register⁽¹⁾
Bit
Name Default
Function
Comments
7
trim_s
6
tre_3
5
tre_2
4
tre_1
3
tre_0
0: LC trim switches are defined
by result of Calibrate Antenna
0
command, see Table 9
1: LC trim switches are defined
Defines source of driving switches on TRIMx pins
by bits tre_x written in this
register
0 MSB
0
-
0
-
0 LSB
LC trim switches are defined by data written in
this register in case trim_s=1. A bit set to 1 switch
on transistor on TRIM1_x and TRIM2_x pin.
2
-
0
1
-
0
-
-
0
-
0
1. Default setting takes place at power-up and after Set Default command.
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