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@ -7,7 +7,7 @@ most USB hubs are super cheap and crappy, leading to poor connection and data tr |
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there are industrial USB hubs, but they are bulky and very expensive. |
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to solve this issue I decided to design my own USB hub, tailored to my needs. |
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when developing and testing hardware, you often end with a lot of USB devices connected. |
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when developing and testing hardware, you often end with a lot of USB devices connected (serial debugger, programmer, logic analyzer, ...). |
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USB allows to have up to 128 devices, but only with a maximum depth of 7. |
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thus you are only allowed to have a maximum of 5 USB hubs between computer and devices, and I often have to plan my setup to not reach this limit. |
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most 7-port USB hubs use two 4-port USB hub, the seconds being connected to the first. |
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@ -15,7 +15,7 @@ there are some exceptions to that, but they are rare, old, and often not adverti |
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this heavily limits the actual number of end devices. |
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the CuVoodoo USB hub is a 7-port flat USB hub, preventing reaching this limit too fast. |
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the incoming and outgoing USB ports are individually ESD protected. |
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the upstream and downstream USB ports are individually ESD protected. |
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this safety becomes important when developing, testing, and handling bare electronic devices. |
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this also comes in handy when connecting circuit with different ground potentials. |
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ESD protections already saved my day twice this way. |
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@ -27,7 +27,7 @@ it if does, there is very probably an issue with the device. |
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this protection allows to isolate the faulty device and not have it affect all other connected devices, or the hub itself. |
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see `current limitation` below for more details. |
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each output port is power controlled. |
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each downstream port is power controlled. |
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this allows to remotely switch on and off individual devices. |
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this is an important requirement when developing and testing devices, which require a power cycle. |
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additionally, a switch next to the USB port can force the power off state. |
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@ -37,7 +37,7 @@ this allows to use higher voltage power supplies to provide enough current to al |
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the 5V are not feed back to the host. |
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each USB port comes with a high voltage output power port, connected to the high voltage input port. |
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this allows to power devices which require more than 5V (e.g. 12V externally powered devices). |
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this allows to power devices which require more than 5V, with a maximum or 5A, such as 12V externally powered devices. |
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these power outputs are controllable along the USB port. |
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as with the 5V USB power output, this allows to remotely switch on an off individual devices. |
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