Maxim 155MBPS Manuals

The MAX3738 is a +3.3V laser driver designed for multi-rate transceiver modules with data rates from 155Mbps to 2.7Gbps. Lasers can be DC-coupled to the MAX3738 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 MAX3738 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, make the MAX3738 ideal for driving FP/DFB lasers in fiber optic modules. External resistors set the required laser current levels. The MAX3738 provides transmit disable control (TX_DISABLE), single-point fault tolerance, bias-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 MAX3738 is compliant with the SFF-8472 transmitter diagnostic and SFP MSA timing requirements. The MAX3738 is offered in a 4mm x 4mm, 24-pin thin QFN package and operates over the extended -40°C to 85°C ambient temperature range, and at a supply voltage of 3.3V.

The MAX3263 is a complete, easy-to-program, single +5V-powered, 155Mbps laser diode driver with complementary enable inputs and automatic power control (APC). The MAX3263 accepts differential PECL inputs and provides complementary output currents. A temperature-stabilized reference voltage is provided to simplify laser current programming. This allows modulation current to be programmed up to 30mA and bias current to be programmed from up to 60mA with two external resistors. An APC circuit is provided to maintain constant laser power in transmitters that use a monitor photodiode. Only two external resistors are required to implement the APC function. The MAX3263’s fully integrated feature set includes a TTL-compatible laser failure indicator and a programmable slow-start circuit to prevent laser damage. The slow-start is preset to 50ns and can be extended by adding an external capacitor.