MIC3001 Datasheet, PDF (21/74 Pages) Micrel Semiconductor – SFP Management IC with Internal Calibration

MIC3001
When APC is on, i.e., the APCCAL bit in OEMCAL0 is set to
0, the value corresponding to the current temperature is taken
from the MODLUT look-up table, added to MODSET, and
loaded into the V_MOD DAC. When APC is off, the value in
V_MOD is loaded directly into the V_MOD DAC, bypassing the
look-up table entirely. This provides for direct modulation
control for setup and calibration. The MODREF bit deter-
mines the DACs response to higher or lower numeric values.
V_DD
Common-cathode with Common-anode with
monitor photodiode monitor photodiode
V_DD
Common-anode
Common-cathode
Figure 6. Transmitter Configurations
Supported by MIC3001
VMOD Configured As Buffered Voltage Output
DAC
VOUT
VDD-OUT
MODREF
VMOD
Micrel
VMOD–
Output Swing = 0 to VREF or VDDA to (VDDA–VREF)
VMOD Configured As Buffered Voltage Output
DAC
VOUT
VDD-OUT
MODREF
Gain = A = ^R1+R2
R2
Output Swing = 0 to (VREF×A)
VMOD
R1
VMOD–
R2
Figure 7. V_MOD Configured as Voltage Output
with Gain
August 2004
21
M9999-082404