DS1875T+ Maxim Integrated Products, DS1875T+ Datasheet - Page 20

• Manufacturer Part Number: DS1875T+
• Description: IC SFP CTRLR/TRIPLEXER 38-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of DS1875T+

• Applications: Fiber Optics
• Interface: I²C
• Voltage - Supply: 2.85 V ~ 3.9 V
• Package / Case: *
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PON Triplexer and SFP Controller
Figure 4. M3QT Timing
Figure 5. ADC Timing with EN5TO8B = 0
Figure 6. ADC Timing with EN5TO8B = 1
The ADC results (after right-shifting, if used) are com-
pared to high and low alarm and warning thresholds
after each conversion. The alarm values can be used to
trigger the TX-F or FETG outputs. These ADC thresholds
are user programmable through the I
well as masking registers that can be used to prevent
the alarms from triggering the TX-F and FETG outputs.
Table 3. ADC Default Monitor Ranges
20
Temperature (°C)
V
MON1–MON8 (V)
CC
TEMP
(V)
______________________________________________________________________________________
SIGNAL
CAPTURE ALARM
TRIP CONDITION
(UNLATCHED)
M3QT ALARM
V
CC
(525kHz)
mCLK
MON1
SIGNAL
127.996
6.5528
2.4997
+FS
MON2
t
FRAME2
7FFF
FFF8
FFF8
HEX
+FS
MON3
MON4
ONE ADC CYCLE
SIGNAL
MON4
TEMP
2
-128
C interface, as
-FS
0
0
MON5
V
CC
8000
0000
0000
HEX
-FS
MON6
MON1
t
FRAME1
MON2
TEMP
There are 10 analog channels that are digitized in a
sequential fashion. The MON5–MON8 channels are
sampled depending on the state of the EN5TO8B bit in
Table 02h, Register 89h. If the bit is programmed to
logic 0, the ADC cycles through temperature, V
MON1–MON4 (Figure 5). If the bit is programmed to
logic 1, all 10 channels are digitized, including chan-
nels MON5–MON8 (Figure 6). In this mode (EN5TO8B
= 0), each of MON5–MON8 is sampled on alternate
cycles, as shown in Figure 5. The total time required to
convert one set of channels is the sequential ADC
cycle time, t
MON3
V
CC
FRAME1
MON4
MON1
TEMP
or t
MON2
t
FRAME2
FRAME2
MON3
(see Figure 6).
MON4
MON7
ADC Timing
CC
MON8
, and