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LMC555: LMC555 at VS = 3.3V

Part Number: LMC555

Hello, Team

may i know the "Vil", and  "Vih" at Vs = 3.3V condition?

it didn`t show on datasheet.

  • Hello,

    We cannot assure specifications outside of the product datasheet conditions. Looking at the table the output swing conditions show that at a supply voltage of 12V with an output current of -10mA the part can reach a minimum of 10.5V or 1.5V from the supply rail. For a 5V supply with Io = -2mA the device can reach a minimum of 5-4.4V or 0.6V from the supply rail. Operating the device at 1.5V with Io = -0.25mA the output can reach a minimum of 1.5V - 1V = 0.5V from the supply rail. 

    Based on these observations, operating the device with a supply of 3.3V I would expect VOH to fall within the specifications of the 1.5V - 5V supply or between 0.5V and 0.6V for the output swing high. Loading the device with different currents will cause the output to deviate from the specifications within the data sheet. 

    Based on the observations for VOL in the product data sheet I would expect the output to fall between the 1.5V and 5V specification of 0.4V and 0.6V. The output current will affect the output swing of both High and Low voltages. With higher output currents the output swing will increase, meaning that the output will reach a value further away from the supply and ground. 

    Best Regards,

    Chris Featherstone