DS1873T+ Maxim Integrated Products, DS1873T+ Datasheet - Page 81

• Manufacturer Part Number: DS1873T+
• Description: IC CTLR SFP+ ANLG LDD 28-TQFN
• Manufacturer: Maxim Integrated Products
• Type: Laser Diode Controllerr

Specifications of DS1873T+

• Number Of Channels: 1
• Voltage - Supply: 2.85 V ~ 3.9 V
• Current - Supply: 2.5mA
• Operating Temperature: -40°C ~ 95°C
• Package / Case: 28-WFQFN Exposed Pad
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 90-1873T+000

Table 07h, Register 80h–C7h: DAC1 LUT
Table 06h, Register F8h–FFh: HBIAS LUT
80h–C7h
F8h–FFh
SFP+ Controller with Analog LDD Interface
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
High bias alarm threshold (HBATH) is a digital clamp used to ensure that the DAC setting for BIAS currents does
not exceed a set value. The table below shows the range of temp for each byte’s location. The table shows a
rising temperature; for a falling temperature there is 1°C of hysteresis.
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
The DAC1 LUT is a set of registers assigned to hold the PWM profile for DAC1. The values in this table
determine the set point for DAC1. The temperature measurement is used to index the LUT (TINDEX, Table 02h,
Register 81h) in 2°C increments from -40°C to +102°C, starting at Register 80h in Table 07h. Register 80h
defines the -40°C to -38°C DAC1 value, Register 81h defines -38°C to -36°C DAC1 value, and so on. Values
recalled from this EEPROM memory table are written into the DAC1 VALUE (Table 02h, Registers 84h–85h)
location, which holds the value until the next temperature conversion. The part can be placed into a manual
mode (DAC1 EN bit, Table 02h, Register 80h), where DAC1 can be directly controlled for calibration. If
temperature compensation is not required by the application, program the entire LUT to the desired DAC1 set
point.
F8h
F9h
FAh
FBh
FCh
FDh
FEh
FFh
BIT 7
BIT 7
______________________________________________________________________________________
2
2
7
7
Less than or equal to -8°C
Greater than -8°C up to +8°C
Greater than +8°C up to +24°C
Greater than +24°C up to +40°C
Greater than +40°C up to +56°C
Greater than +56°C up to +72°C
Greater than +72°C up to +88°C
Greater than +88°C
2
2
6
6
00h
PW2 or (PW1 and RWTBL46) or (PW1 and RTBL46)
PW2 or (PW1 and RWTBL46)
Nonvolatile (EE)
00h
PW2 or (PW1 and RWTBL78) or (PW1 and RTBL78)
PW2 or (PW1 and RWTBL78)
Nonvolatile (EE)
2
2
5
5
2
2
4
4
2
2
3
3
Table 07h Register Descriptions
2
2
2
2
2
2
1
1
BIT 0
BIT 0
2
2
0
0
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