Datasheet

Note 1: All voltages are referenced to ground. Current into the IC is positive, and current out of the IC is negative.
Note 2: Inputs are at supply rail. Outputs are not loaded.
Note 3: Eight ranges allow the full-scale range to change from 312mV to 1.25V.
Note 4: The output impedance of the device is proportional to its scale setting. For instance, if using the 1/2 scale, the output
impedance is 1.5kΩ.
Note 5: This parameter is guaranteed by design.
Note 6: Full-scale is programmable.
Note 7: A temperature conversion is completed and the MODULATION register value is recalled from the LUT and V
CC
has been
measured to be above the VCC LO alarm.
Note 8: The timing is determined by the choice of the SAMPLE RATE setting (see Table 02h, Register 88h).
Note 9: This specification is the time it takes from MON3 voltage falling below the LLOS trip threshold to LOSOUT asserted high.
Note 10: This specification is the time it takes from MON3 voltage rising above the HLOS trip threshold to LOSOUT asserted low.
Note 11: Assuming an appropriate initial step is programmed that would cause the power to exceed the APC set point within four
steps, the bias current will be within 3% within the time specified by the binary search time. See the
BIAS and MODULA-
TION Control During Power-Up section.
Note 12: I
2
C interface timing shown is for fast-mode (400kHz) operation. This device is also backward compatible with I
2
C stan-
dard-mode timing.
Note 13: C
B
—the total capacitance of one bus line in pF.
Note 14: EEPROM write begins after a STOP condition occurs.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SCL Clock Frequency f
SCL
(Note 12) 0 400 kHz
Clock Pulse-Width Low t
LOW
1.3 μs
Clock Pulse-Width High t
HIGH
0.6 μs
Bus-Free Time Between STOP and START
Condition
t
BUF
1.3 μs
START Hold Time t
HD:STA
0.6 μs
START Setup Time t
SU:STA
0.6 μs
Data In Hold Time t
HD:DAT
0 0.9 μs
Data In Setup Time t
SU:DAT
100 ns
Rise Time of Both SDA and SCL Signals t
R
(Note 13) 20 + 0.1C
B
300 ns
Fall Time of Both SDA and SCL Signals t
F
(Note 13) 20 + 0.1C
B
300 ns
STOP Setup Time t
SU:STO
0.6 μs
Capacitive Load for Each Bus Line C
B
400 pF
EEPROM Write Time t
WR
(Note 14) 20 ms
DS1878
SFP+ Controller with Digital LDD Interface
8 _______________________________________________________________________________________
NONVOLATILE MEMORY CHARACTERISTICS
(V
CC
= +2.85V to +5.5V, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
At +25°C 200,000
EEPROM Write Cycles
At +85°C 50,000
I
2
C AC ELECTRICAL CHARACTERISTICS
(V
CC
= +2.85V to +5.5V, T
A
= -40°C to +95°C, timing referenced to V
IL(MAX)
and V
IH(MIN)
, unless otherwise noted.) (Figure 19)