Datasheet

AD7151
Rev. 0 | Page 17 of 28
TIMEOUT REGISTER
When either the approaching or receding timeout elapses (that
is, after the defined number of CDC conversions is counted),
the data average (and thus the thresholds) is forced to follow the
new CDC data value immediately.
Address Pointer 0x0A
8 Bits, Read/Write, Factory Preset 0x86
Table 9. Timeout Register Bit Map
Bit Bits [7:4]
When the timeout register equals 0, timeouts are disabled.
Bits [3:0]
Mnemonic TimeOutApr TimeOutRec
Default 0x08 0x06
DATA AVERAGE
+ SENSITIVITY
LARGE CHANGE IN DAT
A
TOWARDS THRESHOLD
DATA AVERAGE
THRESHOLD
TIME
TIMEOUT APPROACHING
07086-026
The register sets timeouts for the adaptive threshold mode.
The approaching timeout starts when the CDC data crosses the
data average ± sensitivity band toward the threshold, according
to the selected positive, negative, or window threshold mode. The
approaching timeout elapses after the number of conversion cycles
equals 2
TimeOutApr
, where TimeOutApr is the value of the four most
significant bits of the timeout register.
Figure 37. Threshold Timeout Approaching
After a Large Change in CDC Data Toward Threshold
The receding timeout starts when the CDC data crosses the
data average ± sensitivity band away from the threshold,
according to the selected positive or negative threshold mode.
The receding timeout is not used in the window threshold
mode. The receding timeout elapses after the number of
conversion cycles equals 2
TimeOutRec
, where TimeOutRec is the
value of the four least significant bits of the timeout register.
DATA AVERAGE
+ SENSITIVITY
LARGE CHANGE IN DATA
AWAY FROM THE THRESHOLD
DATA AVERAGE
THRESHOLD
TIME
TIMEOUT RECEDIN
G
07086-027
Figure 38. Threshold Timeout Receding
After a Large Change in CDC Data Away from Threshold