IC-NQL Datasheet, PDF (17/24 Pages) IC-Haus GmbH – 13-bit Sin/D CONVERTER WITH SSI INTERFACE

iC-NQL
13-bit Sin/D CONVERTER WITH SSI INTERFACE
SIGNAL MONITORING and ERROR MESSAGES
Rev B1, Page 17/24
SELAMPL
AMPL
Code
0x00
0x01
0x02
0x03
Code
0x04
0x05
0x06
0x07
Notes
Adr 0x0C, Bit 2
Adr 0x0C, Bit 1:0
Max ( |Sin| , |Cos| )
Voltage threshold V_th
Output amplitude*
0.60 x VDDA
1.4 Vpp (0.28 x VDDA)
0.64 x VDDA
2.0 Vpp (0.40 x VDDA)
0.68 x VDDA
2.6 Vpp (0.51 x VDDA)
0.72 x VDDA
3.1 Vpp (0.62 x VDDA)
Sin² + Cos²
V_thmin ↔ V_thmax
Output amplitude*
0.48 ↔ 0.68 x VDDA
2.4 Vpp ↔ 3.4 Vpp
0.56 ↔ 0.76 x VDDA
2.8 Vpp ↔ 3.8 Vpp
0.64 ↔ 0.84 x VDDA
3.2 Vpp ↔ 4.2 Vpp
0.72 ↔ 0.92 x VDDA
3.6 Vpp ↔ 4.6 Vpp
*) Entries are calculated with VDDA = 5 V.
Table 24: Signal Amplitude Monitoring
Vpp
Vth
Figure 13: Signal monitoring of minimum amplitude.
Vthmax
Vthmin
Figure 14: Sin² + Cos² signal monitoring.
AERR
Code
0x00
0x01
Adr 0x03, Bit 1
Amplitude error message
disabled
enabled
Table 25: Amplitude Error
FERR
Code
0x00
0x01
Note
Adr 0x03, Bit 0
Excessive frequency error message
disabled
enabled
Input frequency monitoring is operational for
resolutions ≥ 16
Table 26: Frequency Error
Configuration Error
-
Messaging always released
Table 27: Configuration Error
Error Keys
Failure Mode
No error
Amplitude error
Frequency error
Configuration
Undervoltage
System error
Pin NERR
HI
LO/HI = 75 %
(AERR = 0: HI)
LO/HI = 50 %
(FERR = 0: HI)
LO
LO
NERR = low caused
by an external error
signal
Error bits E1, E0 with
SSI
11
01
(11)
10
(11)
00
00
00
Table 28: Error Keys
Each phase in the configuration process is signaled by
NERR = low; the signal is only reset following a suc-
cessful CRC (cyclic redundancy check).
If the data transfer from the EEPROM is faulty and the
CRC unsuccessful, then the configuration phase is au-
tomatically repeated.
The process aborts following a third unsuccessful at-
tempt and the error message output remains set to low.
To enable the successful diagnosis of faults other types
of error are signaled at NERR using a PWM code as
given in the key on the left.
Two error bits are provided to enable communication
via the SSI interface; these bits can decode four differ-
ent types of error. If NERR is held at low by an external
source, such as an error message from the system, for
example, this can also be verified via the SSI interface.
Error events are stored for the SSI data output and
deleted afterwards. Errors at NERR are displayed for a
minimum of ca. 10 ms, as far as no SSI readout causes
a deletion.
If an error in amplitude occurs the conversion pro-
cess is terminated and the incremental output signals
halted. An error in amplitude rules out the possibility of
an error in frequency.