MAX3643ETG+ Maxim Integrated Products, MAX3643ETG+ Datasheet - Page 13

• Manufacturer Part Number: MAX3643ETG+
• Description: IC LASR DRVR 2.5GBPS 3.6V 24TQFN
• Manufacturer: Maxim Integrated Products
• Type: Laser Diode Driver (Fiber Optic)r

Specifications of MAX3643ETG+

• Data Rate: 2.5Gbps
• Number Of Channels: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 32mA
• Current - Modulation: 85mA
• Current - Bias: 70mA
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 24-TQFN Exposed Pad
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

See Figure 5 for setting up the single-ended LVTTL or
LVCMOS biasing for burst enable.
To minimize inductance, keep the connections
between the MAX3643 output pins and laser diode as
close as possible. Place a bypass capacitor as close
as possible to each V
to minimize stray parasitic capacitance on the BIAS
and MDIN pins. Use good high-frequency layout tech-
niques and multilayer boards with uninterrupted
ground planes to minimize EMI and crosstalk.
Using the MAX3643 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 can occur.
The exposed paddle on the 24-pin TQFN provides a
very low thermal resistance path for heat removal from
the IC. The pad is also electrical ground on the
MAX3643 and must be soldered to the circuit board
ground for proper thermal and electrical performance.
Refer to Maxim Application Note 862: HFAN-08.1:
Thermal Considerations of QFN and Other Exposed-
Paddle Packages for additional information.
155Mbps to 2.5Gbps Burst-Mode Laser Driver
Running Burst-Enable Single-Ended
Applications Information
______________________________________________________________________________________
CC
Laser Safety and IEC 825
Exposed-Paddle Package
Layout Considerations
connection. Take extra care
Figure 5. Single-Ended LVCMOS or LVTTL Biasing for Burst
Enable
Figure 6. Simplified Input Circuit Schematic
LVTTL OR LVCMOS HIGH
LVTTL OR LVCMOS LOW
IN+/BEN+
IN-/BEN-
V
V
CC
CC
MAX3643
5kΩ
5kΩ
R
V
R
4
R
CC
R
3
5
6
= 3kΩ
= 5kΩ
= 5kΩ
= 9kΩ
16kΩ
24kΩ
Interface Model
V
V
CC
CC
V
CC
IN+
IN-
BEN+
BEN-
MAX3643
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