When USB3.0 was introduced, offering theoretical data signaling rates of 5Gbits/s compared with the 480Mbits/s available from USB2.0, the protocol became significantly more useful across a variety of applications. The latest standard to be published, USB3.1, further increases performance to 10Gbits/s and reduces line encoding overhead. All flavors use a Type A standard plug as the interface to the host machine. To house small PCBs using USB as the external power and signal interconnect, Hammond Manufacturing has extended its 1551 miniature family with three new sizes: 1.38, 1.97 or 2.56 inches (35, 50 or 65mm) long, 0.79, 0.98 or 1.18 inches (20, 25 or 30mm) wide respectively, all 0.61 inches (15.5mm) high. According to Hammond, the sizes have been chosen after customer consultation to provide prototype builders and small volume OEMs room for their PCB.
The 1551USB IP54 ABS enclosures, www.hammondmfg.com/1551USB.htm, are a traditional lid and base design. All versions feature a dedicated cut-out for a standard USB Type A plug in one end and have a recess in the lid for an inlay, label or HMI keypad. The two smaller units have two PCB standoffs molded into the base; the largest one has four.
