MAX3261 is a complete, easy-to-program, single +5V-powered, 1.25Gbps laser diode driver with complementary enable inputs and automatic power control (APC). The MAX3261 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 up to 60mA with two external resistors. Complementary enable inputs allow the MAX3261 to interface with open-fiber-control architecture—a feature not found in other 1.25Gbps laser diode drivers. An APC circuit is provided to maintain constant laser power in transmitters that use a monitor photodiode. Only two external components are required to implement the APC function. The MAX3261’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.
The MAX3261 laser driver provides a complete solution for 1.25 Gbps optical transmitters. It operates from a single +5 V supply, accepts differential PECL inputs, and includes automatic power control (APC) that maintains constant laser output using a monitor photodiode. The device features complementary enable inputs for open‑fiber‑control architectures and a TTL‑compatible failure indicator.
The datasheet details electrical characteristics, pin functions, typical operating curves, and design guidelines for high‑speed board layout, bias network compensation, and safety considerations. Ordering information and package options (32‑lead TQFP) are also provided.
| Supply Voltage (Vcc) | +4.75 V to +5.25 V |
|---|---|
| Rise Time | <250 ps |
| Operating Temperature Range | -40 °C to +85 °C |
The device operates from +4.75 V to +5.25 V supply voltage.
Only two external components are required to implement the APC function.