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 internally 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 modulation current of 40mAP-P to 120mAP-P, with an edge speed of 23ps (typical 20% to 80%). This modulation current reflects a modulation voltage of 1.0VP-P to 3.0VPP single ended or 2.0VP-P to 6.0VP-P differential.
The MAX3942 also includes an adjustable pulse-width control circuit to precompensate for asymmetrical modulator 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.

Features
♦ 23ps Edge Speed
♦ Single-Ended Modulation Voltage Up to 3VP-P
♦ Differential Modulation Voltage Up to 6VP-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