Datasheet

______________________________________________________________________________________ 23
MAX3946
1Gbps to 11.3Gbps, SFP+ Laser Driver
with Laser Impedance Mismatch Tolerance
Table 6. Register Summary (continued)
REGISTER
FUNCTION/
ADDRESS
REGISTER
NAME
NORMAL
MODE
SETUP
MODE
BIT
NUMBER/
TYPE
BIT NAME
DEFAULT
VALUE
NOTES
Transmitter
Status Register 2
Address =
H0x07
TXSTAT2
R R 3 (sticky) IMODERR X
Warning increment result
> IMODMAX
R R 2 (sticky) IBIASERR X
Warning increment result
> IBIASMAX
R R 1 (sticky) TXED X Tx edge detection
Bias Current
Setting Register
Address =
H0x08
SET_IBIAS
R RW 7 SET_IBIAS[8] 0
MSB bias DAC
R RW 6 SET_IBIAS[7] 0
R RW 5 SET_IBIAS[6] 0
R RW 4 SET_IBIAS[5] 0
R RW 3 SET_IBIAS[4] 0
R RW 2 SET_IBIAS[3] 0
R RW 1 SET_IBIAS[2] 0
R RW 0 SET_IBIAS[1] 1
Accessible through
REG_ADDR = H0x0D
7 SET_IBIAS[0] 0
LSB bias DAC
Modulation
Current Setting
Register
Address =
H0x09
SET_IMOD
R RW 7 SET_IMOD[8] 0
MSB modulation DAC
R RW 6 SET_IMOD[7] 0
R RW 5 SET_IMOD[6] 0
R RW 4 SET_IMOD[5] 0
R RW 3 SET_IMOD[4] 0
R RW 2 SET_IMOD[3] 1
R RW 1 SET_IMOD[2] 0
R RW 0 SET_IMOD[1] 0
Accessible through
REG_ADDR = H0x0C
7 SET_IMOD[0] 0
LSB modulation DAC
Maximum
Modulation
Current Setting
Register
Address =
H0x0A
IMODMAX
R RW 7 IMODMAX[7] 0
MSB modulation limit
R RW 6 IMODMAX[6] 0
R RW 5 IMODMAX[5] 1
R RW 4 IMODMAX[4] 0
R RW 3 IMODMAX[3] 0
R RW 2 IMODMAX[2] 0
R RW 1 IMODMAX[1] 0
R RW 0 IMODMAX[0] 0
LSB modulation limit
Maximum Bias
Current Setting
Register
Address =
H0x0B
IBIASMAX
R RW 7 IBIASMAX[7] 0
MSB bias limit
R RW 6 IBIASMAX[6] 0
R RW 5 IBIASMAX[5] 1
R RW 4 IBIASMAX[4] 0
R RW 3 IBIASMAX[3] 0
R RW 2 IBIASMAX[2] 0
R RW 1 IBIASMAX[1] 0
R RW 0 IBIASMAX[0] 0
LSB bias limit