Datasheet

DS1878
SFP+ Controller with Digital LDD Interface
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Table 08h Register Descriptions
Table 08h, Register 80h–A3h: DAC2 LUT
FACTORY DEFAULT 00h
READ ACCESS PW2 or (PW1 and RWTBL78) or (PW1 and RTBL78)
WRITE ACCESS PW2 or (PW1 and RWTBL78)
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 DAC2 LUT is set of registers assigned to hold the PWM profile for DAC2. The values in this table determine
the set point for DAC2. 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
DAC2 value, Register 81h defines -36°C to -32°C DAC2 value, and so on. Values recalled from this EEPROM
memory table are written into the DAC2 VALUE (Table 02h, Registers 86h–87h) location that holds the value unti l
the next temperature conversion. The device can be placed into a manual mode (DAC2 EN bit, Table 02h,
Register 80h), where DAC2 can be directly controlled for calibration. If temperature compensation is not required
by the application, program the entire LUT to the desired DAC2 set point. The DAC2TC bit determines whether
the 8-bit LUT values are loaded into the upper 8 bits or lower 8 bits of the 9-bit DAC2. See the Delta-Sigma
Outputs (DAC1 and DAC2) section for more information.
FACTORY DEFAULT 00h
READ ACCESS N/A
WRITE ACCESS N/A
MEMORY TYPE Nonvolatile (EE)
These registers are reserved.
Table 08h, Register A4h–A7h: RESERVED