Datasheet

DS1878
SFP+ Controller with Digital LDD Interface
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Table 02h, Register B9h: COMP RANGING
FACTORY DEFAULT 00h
READ ACCESS PW2
WRITE ACCESS PW2
MEMORY TYPE Nonvolatile (SEE)
B9h RESERVED BIAS
2
BIAS
1
BIAS
0
RESERVED APC
2
APC
1
APC
0
BIT 7 BIT 0
The upper nibble of this byte controls the full-scale range of the quick-trip monitoring for BIAS. The lower nibble of
this byte controls the full-scale range for the quick-trip monitoring of the APC reference as well as the closed-loop
monitoring of APC.
BIT 7 RESERVED (Default = 0)
BITS 6:4
BIAS[2:0]: BIAS Full-Scale Ranging. 3-bit value to select the FS comparison voltage for BIAS found
on MON1. Default is 000b and creates an FS of 1.25V.
BIAS[2:0] % OF 1.25V FS VOLTAGE (V)
000b 100.00 1.250
001b 80.00 1.000
010b 66.67 0.833
011b 50.00 0.625
100b 40.00 0.500
101b 33.33 0.417
110b 28.57 0.357
111b 25.00 0.313
BIT 3 RESERVED (Default = 0)
BITS 2:0
APC[2:0]: APC Full-Scale Ranging. 3-bit value to select the FS comparison voltage for MON2 with
the APC. Default is 000b and creates an FS of 2.5V.
APC[2:0] % OF 2.50V FS VOLTAGE (V)
000b 100.00 2.500
001b 80.00 2.000
010b 66.67 1.667
011b 50.00 1.250
100b 40.00 1.000
101b 33.33 0.833
110b 28.57 0.714
111b 25.00 0.625