MAX3942 Datasheet, PDF (1/10 Pages) Maxim Integrated Products – 10Gbps Modulator Driver

19-2934; Rev 1; 6/07
10Gbps Modulator Driver
General Description
The MAX3942 is designed to drive high-speed optical
modulators at data rates up to 10.7Gbps. It functions as
a modulation circuit, with an integrated control op amp
externally programmed by a DC voltage.
A high-bandwidth, fully differential signal path is inter-
nally implemented to minimize jitter accumulation. When
a clock signal is available, the integrated data-retiming
function can be selected to reject input-signal jitter.
The MAX3942 receives differential CML signals (ground-
referenced) with on-chip line terminations of 50Ω. Each
of the differential outputs has an on-chip 50Ω resistor for
back termination. The driver is able to deliver a modula-
tion current of 40mA_P-P to 120mA_P-P, with an edge
speed of 23ps (typical 20% to 80%). This modulation
current reflects a modulation voltage of 1.0V_P-P to 3.0V_P-
P ^{single ended or 2.0V}P-P ^{to 6.0V}P-P ^{differential.}
The MAX3942 also includes an adjustable pulse-width
control circuit to precompensate for asymmetrical mod-
ulator characteristics. It is available in a compact 4mm
✕ 4mm, 24-pin thin QFN package and operates over
the -40°C to +85°C temperature range.
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX3942ETG -40°C to +85°C 24 Thin QFN (4mm
4mm)
MAX3942ETG+ -40°C to +85°C 24 Thin QFN (4mm
4mm)
+Denotes a lead-free package.
Features
♦ 23ps Edge Speed
♦ Single-Ended Modulation Voltage Up to 3V_P-P
♦ Differential Modulation Voltage Up to 6V_P-P
♦ Selectable Data-Retiming Latch
♦ Up to 10.7Gbps Operation
♦ 50Ω On-Chip Input and Output Terminations
♦ Pulse-Width Adjustment
♦ Enable and Polarity Controls
♦ ESD Protection
Applications
Mach Zehnder Modulators
Packaged Direct-Modulated Lasers
SONET OC-192 and SDH STM-64 Transmission
Systems
DWDM Systems
Long/Short-Reach Optical Transmitters
10Gbps Ethernet
Pin Configuration appears at end of data sheet.
Typical Application Circuit
-5.2V
50Ω
DATA+
MAX3952 _DATA-
10Gbps
SERIALIZER
CLK+
CLK-
0.01μF
0.01μF
0.01μF
0.01μF
PLRT MODEN RTEN
GND
50Ω
DATA+
OUT-
50Ω
DATA-
50Ω
CLK+
MAX3942
50Ω
CLK-
PWC+ PWC-
2kΩ
-5.2V
MODSET
+
VMODSET
-
OUT+
VEE
-5.2V
L2
0.01μF
50Ω
50Ω
MACH ZEHNDER
MODULATOR
L1
0.01μF
50Ω
-5.2V
1000pF
0.1μF
L1 AND L2 ARE HIGH-FREQUENCY FERRITE BEADS
REPRESENTS A CONTROLLED-IMPEDANCE TRANSMISSION LINE.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.