DS1877T+ Maxim Integrated Products, DS1877T+ Datasheet - Page 55

• Manufacturer Part Number: DS1877T+
• Description: IC CTLR/MON SFP 1-2CH 28TQFN
• Manufacturer: Maxim Integrated Products
• Type: SFP+ Controllerr

Specifications of DS1877T+

• Input Type: Logic
• Output Type: Logic
• Interface: I²C
• Current - Supply: 2.5mA
• Mounting Type: Surface Mount
• Package / Case: 28-WFQFN exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 90-1877T+000

Table 02h, Register BCh: LOS RANGING
BCh
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
A2h AND B2h MEMORY
MEMORY TYPE
This register controls the full-scale range of the QT monitoring for the RSSI1 differential inputs.
RESERVED
BITS 7, 3
BITS 6:4
BITS 2:0
BIT 7
RESERVED (default = 0)
HLOS1[2:0]: HLOS1 full-scale ranging: 3-bit value to select the full-scale comparison voltage for
high LOS found on RSSI1. Default is 000b and creates a full scale of 1.25V.
LLOS1[2:0]: LLOS1 full-scale ranging: 3-bit value to select the full-scale comparison voltage for
low LOS found on RSSI1. Default is 000b and creates a full scale of 1.25V.
SFP Controller for Dual Rx Interface
HLOS1
2
HLOS1[2:0]
LLOS1[2:0]
000b
001b
010b
011b
100b
101b
110b
111b
000b
001b
010b
011b
100b
101b
110b
111b
00h
PW2 or (PW1 and RWTBL2) or (PW1 and RTBL2)
PW2 or (PW1 and RWTBL2)
Common A2h and B2h memory locations
Nonvolatile (SEE)
HLOS1
1
1
HLOS1
0
% OF 1.25V
% OF 1.25V
RESERVED
100.00
100.00
80.02
66.69
50.05
40.05
33.38
28.62
25.04
80.02
66.69
50.05
40.05
33.38
28.62
25.04
LLOS1
2
FS VOLTAGE (V)
FS VOLTAGE (V)
LLOS1
1.0003
0.8336
0.6256
0.5006
0.4172
0.3578
1.0003
0.8336
0.6256
0.5006
0.4172
0.3578
1.250
0.313
1.250
0.313
1
LLOS1
BIT 0
0
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