DS1875T+TR MAXIM [Maxim Integrated Products], DS1875T+TR Datasheet - Page 85

• Manufacturer Part Number: DS1875T+TR
• Description: PON Triplexer and SFP Controller
• Manufacturer: MAXIM [Maxim Integrated Products]

Table 02h, Register FBh to FCh: BIAS DAC
Table 02h, Register FDh: BIAS OL
FBh
FCh
FDh
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
The bias open-loop bit (BOL) reflects the status of the BIAS current-control loop. If it is 1, the loop is open and
the DS1875 is controlling the BIAS output from the LUT. If it is 0, the loop is closed and the BIAS output is
controlled by active feedback from the BMD pin. The remaining bits are the digital value used for the BIAS
output regardless of the value of OL.
The digital value used for BIAS at power-on and during open loop. It is recalled from Table 08h at the adjusted
memory address found in TINDEX. This register is updated at the end of the temperature conversion. The
correct value depends on the value of BOLFS (Table 02h, Register 89h, bit 3).
If BOLFS = 0, BIAS OL[7:0] = I
If BOLFS = 1, BIAS OL[7:0] = I
BIT 7
BIT 7
BOL
______________________________________________________________________________________
2
2
7
7
2
2
0
6
6
PON Triplexer and SFP Controller
8000h
PW2
N/A
Volatile
00h
PW2
PW2 and APC EN = 1
Volatile
BIAS
BIAS
2
2
2
12
[11:4].
5
5
[12:5].
2
2
2
11
4
4
2
2
2
10
3
3
2
2
2
2
9
2
2
2
2
8
1
1
BIT 0
BIT 0
2
2
2
7
0
0
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