DS1875T+ Maxim Integrated Products, DS1875T+ Datasheet - Page 87

• 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

Table 03h, Register 80h to FFh: PW2 EEPROM
Table 04h, Register 80h to C7h: MODULATION LUT
80h to C7h
80h to FFh
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
The digital value for the modulation DAC output.
The MODULATION LUT is a set of registers assigned to hold the temperature profile for the modulation DAC.
The values in this table combined with the MOD bits in the MOD RANGING register (Table 02h, Register 8Bh)
determine the set point for the modulation voltage. The temperature measurement is used to index the LUT
(TINDEX, Table 02h, Register 81h) in 2°C increments from -40°C to +102°C, starting at 80h in Table 04h.
Register 80h defines the -40°C to -38°C MOD output, Register 81h defines the -38°C to -36°C MOD output, and
so on. Values recalled from this EEPROM memory table are written into the MOD DAC (Table 02h, Register 82h)
location that holds the value until the next temperature conversion. The DS1875 can be placed into a manual
mode (MOD EN bit, Table 02h, Register 80h), where MOD DAC is directly controlled for calibration. If the
temperature compensation functionality is not required, then program the entire Table 04h, to the desired
modulation setting.
PW2-protected EEPROM.
BIT 7
BIT 7
______________________________________________________________________________________
EE
2
7
EE
2
6
PON Triplexer and SFP Controller
00h
PW2
PW2
Nonvolatile (EE)
00h
PW2
PW2
Nonvolatile (EE)
EE
2
5
EE
2
4
EE
2
3
Table 03h Register Descriptions
Table 04h Register Descriptions
EE
2
2
EE
2
1
BIT 0
BIT 0
EE
2
0
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