Datasheet

DS1886
SFP and PON ONU Controller
with Digital LDD Interface
27Maxim Integrated
F8h and FDh). See Figure 12a and Figure 12b for non-
latched and latched operation. Figure 12c describes
this TXFOUT behavior during power-on. Latching of the
alarms is controlled by CNFGB and CNFGC Registers
(A2h Table 02h, Register 8Ah and A2h Table 02h,
Register 8Bh).
The DS1886 monitors the IMODOVFL and IBIASOVFL
bits in the MAX3710 DPCSTAT register. If any of these
bits is set, the user can optionally cause TXFOUT to be
set. A mask bit, BIASMODOVFL_FLT in A2h Table 02h,
Register 8Bh, must be set to enable this functionality.
Die Identification
The DS1886 has an ID hardcoded in its die. Two
registers (DEVICE ID A2h Table 02h, Register CEh and
DEVICE VER A2h Table 02h, Register CFh) are assigned
for this feature. Register CEh reads 84h to identify with
the device as the DS186, and Register CFh reads the
present device version.
Figure 12a. TXFOUT Nonlatched Operation
Figure 12b. TXFOUT Latched
Figure 12c. TXFOUT During Power-On
TXFOUT
DETECTION OF
TXFOUT FAULT
TXFOUT
DETECTION OF
TXFOUT FAULT
TXD OR
TXF RESET
V
POA
V
CC
TXFOUT
1
TXFOUT
2
CONDITION 1: VCC LO ALARM OR WARNING FLAG ENABLED TO CREATE TXF. V
CC
IS ABOVE CORRESPONDING VCC LO ALARM/WARNING THRESHOLD.
CONDITION 2: VCC LO ALARM AND WARNING FLAGS ARE NOT ENABLED.
t
INITR2