Rainbow Electronics DS1862 - Manual (Page 21)

DS1862
XFP Laser Control and Digital Diagnostic IC
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Warning and Alarm Logic Based on
AUX1/2MON, V CC2/3 , Temp, RX-P,
and IBIASMON
The DS1862 is capable of generating an alarm and/or
warning whenever an analog monitored channel goes
out of a user-defined tolerance. Temperature, bias cur-
rent (based on IBIASMON), receive power (based on
RSSI), AUX1MON, AUX2MON, and V
CC2/3
, are moni-
tored channels that generate latched flags. See the fig-
ure below for more detail pertaining to AUX1MON and
AUX2MON. Flags are latched into a high state the first
time a monitored channel goes out of the defined oper-
ating window and for each monitored signal there is a
Mask bit that can be set to prevent the corresponding
alarm or warning flag from being set. Once a flag is set,
it is cleared by simply reading its memory location.
AUX1/2MON LOGIC
AUX1MON (PIN)
AUX2MON (PIN)
MASK BIT
AUX1MON
AUX2MON
ADC
THRESHOLD
AUX1MON
(APD MODE)
LATCHED-APD-
SUPPLY-FAULT
AUX2MON
(APD MODE)
INTERRUPT (PIN)
*COMPARATOR LOGIC IS
DUPLICATED FOR HIGH
AND LOW ALARMS AND
WARNINGS.
C
ADC
THRESHOLD
C
4-BIT UNIT SELECT
LA
TCH
AUX1MON
(LASER WL MODE)
LATCHED-
WAVELENGH-UL
AUX2MON
(LASER WL MODE)
LA
TCH
AUX1MON
(V EE5 MODE)
LATCHED-V
EE5
AUX2MON
(V EE5 MODE)
LA
TCH
AUX1MON
(V CC2 MODE)
LATCHED-V
CC2
AUX2MON
(V CC2 MODE)
LA
TCH
AUX1MON
(TEC MODE)
LATCHED-TEC-
FAULT
AUX2MON
(TEC MODE)
LA
TCH
AUX1MON
(V CC5 MODE)
LATCHED-V
CC5
AUX2MON
(V CC5 MODE)
LA
TCH
AUX1MON
(V CC3 MODE)
LATCHED-V
CC3
AUX2MON
(V CC3 MODE)
LA
TCH
ANY FLAG
CORRESPONDING MASK
BIT
Figure 10. AUX1/2 Monitor Logic