MAX3946ETG+T Maxim Integrated Products, MAX3946ETG+T Datasheet - Page 22

• Manufacturer Part Number: MAX3946ETG+T
• Description: IC LASER DVR SFP 11.3GBPS 24TQFN
• Manufacturer: Maxim Integrated Products
• Type: Laser Diode Driverr

Specifications of MAX3946ETG+T

• Data Rate: 11.3Gbps
• Number Of Channels: 1
• Voltage - Supply: 2.85 V ~ 3.63 V
• Current - Supply: 68mA
• Current - Modulation: 80mA
• Current - Bias: 80mA
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 12-WFQFN, Exposed Pad
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

1.0625Gbps to 11.3Gbps, SFP+ Laser Driver
with Laser Impedance Mismatch Tolerance
The eye crossing at the Tx output can be adjusted using
the SET_PWCTRL register. Table 5 shows these set-
tings. The sign of the number specifies the direction of
Table 5. Eye-Crossing Settings for
SET_PWCTRL
Table 6. Register Summary
22
Transmitter
Control Register
Address =
H0x05
Transmitter
Status Register 1
Address =
H0x06
SET_PWCTRL[3:0]
FUNCTION/
REGISTER
ADDRESS
_____________________________________________________________________________________
1000
1001
1010
1011
1100
1101
1110
1111
Programming Pulse-Width Control
REGISTER
TXSTAT1
TXCTRL
NAME
PWD
-7
-6
-5
-4
-3
-2
-1
0
SET_PWCTRL[3:0]
NORMAL
MODE
R
R
R
R
R
R
R
R
R
R
R
R
R
0111
0110
0101
0100
0011
0010
0001
0000
SETUP
MODE
RW
RW
RW
RW
RW
RW
R
R
R
R
R
R
R
PWD
8
7
6
5
4
3
2
1
NUMBER/
7 (sticky)
6 (sticky)
4 (sticky)
3 (sticky)
2 (sticky)
1 (sticky)
0 (sticky)
TYPE
BIT
5
4
3
2
1
0
pulse-width distortion. The code of 1111 corresponds to
a balanced state for differential output. The pulse-width
distortion is bidirectional around the balanced state (see
the Typical Operating Characteristics section).
Using the MAX3946 laser driver alone does not ensure
that a transmitter design is compliant with IEC 825. The
entire transmitter circuit and component selections must
be considered. Each user must determine the level of
fault tolerance required by the application, recognizing
that Maxim products are neither designed nor authorized
for use as components in systems intended for surgical
implant into the body, for applications intended to sup-
port or sustain life, or for any other application in which
the failure of a Maxim product could create a situation
where personal injury or death could occur.
TXDE_MD[1]
TXDE_MD[0]
BIT NAME
TX_FAULT
TXEQ_EN
SOFTRES
TX_POL
TX_EN
FST[7]
FST[6]
FST[4]
FST[3]
FST[2]
FST[1]
Applications Information
DEFAULT
VALUE
Laser Safety and IEC 825
0
0
0
0
1
1
X
X
X
X
X
X
X
MSB deemphasis mode
LSB deemphasis mode
Input equalization
0: disabled, 1: enabled
Global digital reset
Tx polarity
0: inverse, 1: normal
Tx control
0: disabled, 1: enabled
TX_PORàTX_VCC low-
limit violation
BMON open/shorted to
V
BMAX current exceeded
or open/short to ground
V
low-limit
V
BIAS open or shorted to
ground
Copy of FAULT signal
in case POR bits 6 to 1
reset to 0
CC
TOUT+/-
TOUT+/-
common-mode
low-limit violation
NOTES