Table 06h register descriptions, Ds1874 sfp+ controller with digital ldd interface – Rainbow Electronics DS1874 User Manual

Page 85

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DS1874

SFP+ Controller with Digital LDD Interface

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85

Table 06h Register Descriptions

Table 06h, Register 80h–A3h: APC TE 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 TE 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 in Table 05h. 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 DS1874 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

PW2 or (PW1 and RWTBL246) or (PW1 and RTBL246)

WRITE ACCESS

PW2 or (PW1 and RWTBL246)

MEMORY

TYPE Nonvolatile

(EE)

These registers are reserved.

Table 06h, Register A4h–A7h: RESERVED

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