The voltage of QSFP (Quad Small Form-Factor Pluggable) modules can vary depending on the specific type and configuration of the module. QSFP modules can support various data rates and may have different power supply requirements. Commonly, the voltage requirements for QSFP modules fall within the range of 3.3 volts.

Here are some general points regarding the voltage of QSFP modules:

1. Power Supply Voltage:

• QSFP modules typically operate with a power supply voltage of 3.3 volts (V).

• The 3.3V power supply voltage is common in optical transceivers to ensure compatibility and standardization.

2. Power Consumption:

• QSFP modules have different power consumption levels based on the specific type and data rate they support. Power consumption is measured in watts (W).

3. Power Classes:

• QSFP modules are often categorized into different power classes, such as Class 1, Class 2, and so on. These classes are associated with different power consumption levels.

It's crucial to refer to the datasheet and specifications provided by the manufacturer of the specific QSFP module you are using. The datasheet will provide detailed information about the module's electrical characteristics, including the operating voltage, power consumption, and any other relevant details. 

Keep in mind that advancements in technology and new standards may introduce variations in the voltage requirements of QSFP modules. Always refer to the most up-to-date documentation to ensure accurate information for your specific QSFP modules. 

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