The MAX3737 is a 3.3V laser driver designed for multirate transceiver modules with data rates from 155Mbps to 2.7Gbps. Lasers can be DC-coupled to the MAX3737 for reduced component count and ease of multirate operation.
Laser extinction ratio control (ERC) combines the features of automatic power control (APC), modulation compensation, and built-in thermal compensation. The APC loop maintains constant average optical power. Modulation compensation increases the modulation current in proportion to the bias current. These control loops combined with thermal compensation maintain a constant optical extinction ratio over temperature and lifetime.
The MAX3737 accepts differential data input signals. The wide 5mA to 60mA (up to 85mA AC-coupled) modulation current range and up to 100mA bias current range makes the MAX3737 ideal for driving FP/DFB lasers in fiber-optic modules. External resistors set the required laser current levels. The MAX3737 provides transmit disable control (TX_DISABLE), single-point fault tolerance, bias-current monitoring, modulation-current monitoring, and photocurrent monitoring. The device also offers a latched failure output (TX_FAULT) to indicate faults, such as when the APC loop is no longer able to maintain the average optical power at the required level. The MAX3737 is compliant with the SFF-8472 transmitter diagnostic and SFP MSA timing requirements.
The MAX3737 is offered in a 5mm x 5mm 32-pin thin QFN and QFN package and operates over the -40°C to +85°C extended temperature range.