#85 I like this the best of your entries, bold characters and it looks good how you have expanded the word "DESIGN". Whilst it is probably obvious to anyone who reads the company name, the final character could still be mistaken for a 'J', a small criticism.
#75 - it is difficult to see the circuit detail in the background when the logo is small, I'm looking for a logo that works both large and small with maximum readability of the characters LSD.