iC-NQL
13-bit Sin/D CONVERTER WITH SSI INTERFACE
Rev B1, Page 13/24
MAXIMUM POSSIBLE CONVERTER FREQUENCY
The converter frequency automatically adjusts to the feature can be enabled via the FCTR register. Should
value necessary for the input frequency and resolution. the input frequency exceed the frequency limit of the
This value ranges from zero to a maximum dependent selected converter resolution, the LSB is kept stable
on the oscillator frequency which can be set using reg- and not resolved any further; the interpolation resolu-
ister FCTR.
tion halves.
Serial data output
If the next frequency limit is overshot, the LSB and the
For SSI output the maximum possible converter fre- LSB+1 are kept stable and so on. When the input fre-
quency can be adjusted to suit the maximum input fre- quency again sinks below this frequency limit, the fine
quency; an automatic converter resolution step-down resolution automatically returns.
Max. Possible Converter Frequency For Serial Data Output
Resolution
Protocol Max. Input Frequency
Restrictions
Examples*
Requirements
at high input frequency
finmax [kHz] at resol.
8192 1024 200
FCTR
Min. Res. bin dec SSI
finmax
0x0004
0x4102
0x4202
0x4304
0x4602
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
-
X
X
X
X
X
X
X
X
X
X
X
X
f(OSC)min / 40 / Resolution
–
0.16
0.26
0.53
0.64
1.1
1.27
2.1
4.2
5.1
8.5
16.9
33.8
67.7
135
250
-
6.5
≥ 8
f(OSC)min / 24 / Resolution Rel. angle error 2x increased
10.8
≥ 16
≥ 32
≥ 64
2 x f(OSC)min / 24 / Res.
4 x f(OSC)min / 40 / Res.
4 x f(OSC)min / 24 / Res.
8 x f(OSC)min / 24 / Res.
16 x f(OSC)min / 24 / Res.
32 x f(OSC)min / 24 / Res.
64 x f(OSC)min / 24 / Res.
Rel. angle error 4x increased
Rel. angle error 8x increased
Resolution lowered by factor of 2
Res. lowered by factor of 2-4
Res. lowered by factor of 2-8
Res. lowered by factor of 2-16
Res. lowered by factor of 2-32
21.6
26.0
-
-
-
-
-
-
-
-
0x4A02 ≥ 128
0x4E02 ≥ 256
-
2.1
-
4.2
0x5202
0x5602
≥ 512
-
8.5
≥ 1024
-
16.9
33.8
67.7
135
0x5A02 ≥ 2048
0x5E02 ≥ 4096
-
128 x f(OSC)min / 24 / Res. Res. lowered by factor of 2-64
256 x f(OSC)min / 24 / Res. Res. lowered by factor of 2-128
512 x f(OSC)min / 24 / Res. Res. lowered by factor of 2-256
-
0x6202
Notes
8192
-
-
*) Calculated with fosc()min taken from Electrical Characteristics item A01.
Table 14: Maximum converter frequency for serial data output.
ICHAUS [ IC-HAUS GMBH ]
