The recommended PCB layout for the MAX2680EUT-T involves keeping the input and output traces as short as possible, using a solid ground plane, and placing the device close to the antenna. Additionally, it's recommended to use a 4-layer PCB with a dedicated layer for the RF signal, a layer for the power supply, a layer for the ground plane, and a layer for the digital signals.
The value of the external bias resistor (RBIAS) depends on the desired output power and the voltage supply. A higher value of RBIAS will result in lower output power, while a lower value will result in higher output power. The datasheet provides a formula to calculate the recommended value of RBIAS based on the desired output power and voltage supply.
The MAX2680EUT-T has an operating temperature range of -40°C to +85°C. However, the device's performance may degrade at higher temperatures, and it's recommended to operate the device within a temperature range of -20°C to +70°C for optimal performance.
To ensure proper matching, it's recommended to use a 50Ω antenna and to follow the recommended PCB layout guidelines. Additionally, the device's output impedance can be adjusted by using external matching components, such as capacitors and inductors, to achieve optimal matching with the antenna.
The recommended power supply decoupling scheme for the MAX2680EUT-T involves using a combination of ceramic capacitors and electrolytic capacitors to filter out noise and ripple on the power supply lines. A 10nF ceramic capacitor and a 10μF electrolytic capacitor are recommended for decoupling the power supply.
