Datasheet

DS1878
SFP+ Controller with Digital LDD Interface
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Table 06h Register Descriptions
Table 06h, Register 80h–A3h: APC LUT
FACTORY DEFAULT 00h
READ ACCESS PW2 or (PW1 and RWTBL246) or (PW1 and RTBL246)
WRITE ACCESS PW2 or (PW1 and RWTBL246)
MEMORY TYPE Nonvolatile (EE)
80h–A3h 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
BIT 7 BIT 0
The APC LUT is a set of registers assigned to hold the temperature profile for the APC reference DAC. The
values in this table combined with the APC bits in the COMP RANGING register (Table 02h, Register B9h)
determine the set point for the APC loop. The temperature measurement is used to index the LUT (TINDEX, Table
02h, Register 81h) in 4°C increments from -40°C to +100°C, starting at Register 80h. Register 80h defines the
-40°C to -36°C APC reference value, Register 81h defines the -36°C to -32°C APC reference value, and so on.
Values recalled from this EEPROM memory table are written into the APC DAC (Table 02h, Register CDh)
location that holds the value until the next temperature conversion. The device can be placed into a manual
mode (APC EN bit, Table 02h, Register 80h), where the APC DAC can be directly controlled for calibration. If TE
temperature compensation is not required by the application, program the entire LUT to the desired APC set
point.
FACTORY DEFAULT 00h
READ ACCESS N/A
WRITE ACCESS N/A
MEMORY TYPE Nonvolatile (EE)
These registers are reserved.
Table 06h, Register A4h–A7h: RESERVED