What has changed to make it possible to develop USB3.0

Question

Like I know the transfer speeds are vastly different.

But I don't understand is why they are faster. And why couldn't they have implemented USB 3.0 when they released 1.0? Like what technical breakthrough was required to get transfer speeds that fast?

Was it

• cost?
• capacities of computer? like they couldn't read the data fast enough? Although USB is still well below hard drive transfer speeds
• engineering breakthrough? They found some new material which could transfer at a faster rate? Was this in the cable itself? In the hardware?

Answer 1

I don't know the exact details, because they are hidden in some company archives. But the question itself is somehow funny, because everything in technology evolves, everything gets faster.

Here my guess what changed.

• Smaller production size, ICs got smaller or stayed the same size but got more powerful or faster.
• Production got cheaper, more powerful ICs got cheaper
• It became necessary. Nobody needed a fast BUS System when USB1.0 was developed. Also the connection of a USB Port to the processor in the computer was not fast enough. IDE or SATA is on a different BUS System in the computer.

Mostly technology got smaller and cheaper, and it's always about the price. Who would buy a device that supports USB3.0 when you can't use it because e.g. storage access in the usb stick is not fast enough. So you would throw money out of the window.

I'm sure USB2.0 will still stay around for e.g. HDSPA Modems and USB1.0 for low speed technology like Serial over USB.

Answer 2

For difference between USB 1.0 and USB 2.0 check here:usb-2-0-vs-usb-1-0-and-1-1

USB 2.0 Vs 3.0 Comparison

1. Speed: The advent of USB 2.0 revolutionized the rate of data transfer by providing an amazingly high speed of 480 Mbps, as compared to the meagre rate of 1.5Mbps-12Mbps offered by USB 1.0. After a lot of publicity and delays, the much awaited new specification of USB, i.e. the USB 3.0 was introduced. The USB 3.0 supports the super fast speed of 5Gbps. This makes the new USB 3.0 around ten times faster than the old USB 2.0.

2. Data Rates: There have been defined four distinct speeds of data transfer as low-speed, full-speed, high-speed and super-speed with maximum data throughputs of 1.25x, 10x, 400x and 4166.7x respectively, where, 1x=.15MB/sec. USB 2.0 supports low, full and high speed transfers, whereas USB 3.0 supports all four rates including the super-speed.

3. Real Data Throughput: The above data rates are theoretical, but it is found that in practical applications, the experimental values differ from theoretical values. The actual transfer rates of USB 2.0 Vs USB 3.0 are found to be around 35-40 MB/sec for the 2.0 specification and for 3.0, it may go well above 400 MB/sec.

4. Power: The USB specification has an attractive feature where in the USB device can be powered by the PC or laptop that it is connected to.

5. Type of Transfer: The USB 3.0 supports a dual-simplex simultaneous bi-directional flow of data as opposed to the half duplex unidirectional flow of data in 2.0.