SN74LS07: May I know what is the difference between SN74LS07DE4 and SN74LS07DR ?

Hi Weiji,

In short, there will be no difference between a device labelled SN74xxE4 and SN74xx.

Historically, G4 and E4 suffixes meant that the devices were rated to be “Green” or “Lead Free.” However, as time has passed, all devices have been pushed to these new “Green” or “Lead Free” standards, but the specific part orderables have remained available so that customers have had a consistent orderable part number.

As far as the R, this indicates that the device will come in a reel (typically for large quantities)