topic The connection between K64F output and 74LS07 input is OK? in Kinetis Microcontrollers https://community.nxp.com/t5/Kinetis-Microcontrollers/The-connection-between-K64F-output-and-74LS07-input-is-OK/m-p/617337#M36811 <HTML><HEAD></HEAD><BODY><P>Kinetis K64F output pins are connecting to input pins of SN74LS07 buffer.</P><P>The Vcc of SN74LS07 is 5V.&nbsp;</P><P>It works normally.</P><P>However, I am worried about the reverse current to K64F Vdd (3.3V) from SN74LS07 input pin.<BR />SN74LS07 datasheet says "I_IH is 20uA, I_IL is -0.2mA".</P><P>Are these value no problem for K64F ?</P><P><BR />I had thought that All digital I/O pins are 5V tolerant.<BR />But some people say that "The Kinetis Port pins are only 5V tolerant as inputs. The outputs are not 5V tolerant." in other threads.<BR />Which is true?</P></BODY></HTML> Tue, 18 Apr 2017 03:46:09 GMT masakazunotsu 2017-04-18T03:46:09Z The connection between K64F output and 74LS07 input is OK? https://community.nxp.com/t5/Kinetis-Microcontrollers/The-connection-between-K64F-output-and-74LS07-input-is-OK/m-p/617337#M36811 <HTML><HEAD></HEAD><BODY><P>Kinetis K64F output pins are connecting to input pins of SN74LS07 buffer.</P><P>The Vcc of SN74LS07 is 5V.&nbsp;</P><P>It works normally.</P><P>However, I am worried about the reverse current to K64F Vdd (3.3V) from SN74LS07 input pin.<BR />SN74LS07 datasheet says "I_IH is 20uA, I_IL is -0.2mA".</P><P>Are these value no problem for K64F ?</P><P><BR />I had thought that All digital I/O pins are 5V tolerant.<BR />But some people say that "The Kinetis Port pins are only 5V tolerant as inputs. The outputs are not 5V tolerant." in other threads.<BR />Which is true?</P></BODY></HTML> Tue, 18 Apr 2017 03:46:09 GMT https://community.nxp.com/t5/Kinetis-Microcontrollers/The-connection-between-K64F-output-and-74LS07-input-is-OK/m-p/617337#M36811 masakazunotsu 2017-04-18T03:46:09Z Re: The connection between K64F output and 74LS07 input is OK? https://community.nxp.com/t5/Kinetis-Microcontrollers/The-connection-between-K64F-output-and-74LS07-input-is-OK/m-p/617338#M36812 <HTML><HEAD></HEAD><BODY><P>Dear Masakazu Notsu,</P><P></P><P>All 5V dital I/O are clamped to VSS through a protection diode.</P><P></P><P>Please refer to K64's datasheet, chapter&nbsp;2.2.1 Voltage and current operating requirements for more information:</P><P></P><P><A class="link-titled" href="http://cache.freescale.com/files/microcontrollers/doc/data_sheet/K64P144M120SF5.pdf" title="http://cache.freescale.com/files/microcontrollers/doc/data_sheet/K64P144M120SF5.pdf">http://cache.freescale.com/files/microcontrollers/doc/data_sheet/K64P144M120SF5.pdf</A>&nbsp;</P><P></P><P>Regards,</P><P>Ivan.</P></BODY></HTML> Thu, 20 Apr 2017 22:10:49 GMT https://community.nxp.com/t5/Kinetis-Microcontrollers/The-connection-between-K64F-output-and-74LS07-input-is-OK/m-p/617338#M36812 IvanRuiz 2017-04-20T22:10:49Z