Datasheet

20 _____________________________________________________________________________________
MAX3945
1.0625Gbps to 11.3Gbps,
SFP+ Dual-Path Limiting Amplifier
General Control Register (MODECTRL)
Bits 7 to 0: MODECTRL[7:0]. The MODECTRL register enables a switch between normal and setup modes. The setup
mode is achieved by setting this register to H0x12. MODECTRL must be updated before each write operation.
LOS Timer Setting Register (SET_LOSTIMER)
Bits 6 to 0: SET_LOSTIMER[6:0]. The SET_LOSTIMER register is a 7-bit register that can be set from 0 to 127. See
the Typical Operating Characteristics section for a typical timer period vs. DAC code.
Table 12. Register Map
Bit #
7 6 5 4 3 2 1 0 ADDRESS
Name
MODECTRL[7]
(MSB)
MODECTRL[6] MODECTRL[5] MODECTRL[4] MODECTRL[3] MODECTRL[2] MODECTRL[1]
MODECTRL[0]
(LSB)
H0x0E
Default
Value
0 0 0 0 0 0 0 0
Bit #
7 6 5 4 3 2 1 0 ADDRESS
Name X
SET_
LOSTIMER[6]
(MSB)
SET_
LOSTIMER[5]
SET_
LOSTIMER[4]
SET_
LOSTIMER[3]
SET_
LOSTIMER[2]
SET_
LOSTIMER[1]
SET_
LOSTIMER[0]
(LSB)
H0x12
Default Value X 0 0 0 0 0 0 0
REGISTER
FUNCTION/
ADDRESS
REGISTER
NAME
NORMAL
MODE
SETUP
MODE
BIT NUMBER/
TYPE
BIT NAME
DEFAULT
VALUE
NOTES
Receiver
Control
Register 1
Address =
H0x00
RXCTRL1
R RW 7 RXDE1 0
Rx deemphasis
MSB control with
RXDE_EN = 1
R RW 6 RXDE0 0
Rx deemphasis
LSB control with
RXDE_EN = 1
R RW 5 X 1 Must be set to 1
R RW 4 SOFTRES 0
Soft reset control
bit
R RW 3 BW1 1
Input bandwidth
control with
RATE_SEL = 0:
00: 1GHz
01: 2.1GHz
10: 2.5GHz
11: 3GHz
R RW 2 BW0 1
R RW 1 RATE_SEL 1
Rate-select con-
trol
0: 1G/4G mode
1: fast mode
R RW 0 X 1 Must be set to 1