Usb2514b-aezc-tr qfn-36 USB chip price advantage
Smscusb251xb / Xbi hub series is a set of low-power, configurable, MTT (multi transaction converter) hub controller integrated circuits. The hub provides a downstream port for the embedded USB solution and is fully compliant with USB2 [1] of 0 specification. Each SMSC hub controller can be connected to the upstream port as a full speed or full speed / high speed hub. When it operates as a high-speed hub, it can support low-speed, full speed and high-speed downstream equipment.
All required resistors on the USB port are integrated into the hub. This includes all series of termination resistors, as well as all required pull-down and pull-up resistors on the D + and D pins. The downstream port oriented overcurrent detection input has an internal pull-up resistance.
The usb251xb / Xbi hub series includes programmable functions, such as multitraktm Technology: a dedicated transaction converter (TT) is implemented for each port. Dedicated TTS help maintain consistent full speed data throughput regardless of the number of active downstream connections.
Portmap: provides flexible port mapping and disabling sequences. The downstream ports of the usb251xb / Xbi hub can be reordered or disabled in any order to support multiple platform designs with minimal effort. For any disabled port, the usb251xb / Xbi hub controller will automatically reorder the remaining ports to match the port numbering scheme of the USB host controller.
Portswap: allows the USB signal (D + / D -) to be directly aligned to the connector to avoid uneven tracking length or USB differential signal crossing on the PCB. Phyboost: realize four programmable levels of USB signal driving strength in the downstream port transceiver. Phyboost will also try to restore the integrity of the USB signal.
features
The smscusb251xb / Xbi hub controller provides a default configuration that may be suitable for most applications. The bundle option pin (see section 3.3.1 on page 22) provides additional functionality to enhance the default configuration.
In the default configuration, when the hub is initialized, the following functions can be configured using the bundling option:
Downstream non removable ports where hubs will automatically report as composite devices
Disable downstream ports enable the battery charging option on each port
The usb251xb / Xbi hub controller can also be configured as an SMBus slave by an external i2ceeprom or microcontroller.
When the hub is configured by i2ceeprom or above SMBus, the following configurable functions will be provided:
Port based support for composite devices
Overcurrent sensing and port power control can be selected individually or in combination to match the selection of circuit board components
Customizable supplier ID, product ID and device ID
Configurable USB signal driving strength
Configurable USB differential pair pin position
Configurable delay time for filtering overcurrent detection input
Configurable downstream port power up time reported to the host
Indicates the maximum current consumed by the hub from the USB upstream port
Indication of the maximum current required by the hub controller
Custom string descriptor (up to 31 characters):
Product manufacturer serial number
Battery charging usb251xb / Xbi products are fully compatible with usb251x / Xi / XA / Xai
Product: pin compatible direct plug-in replacement
Use the same PCB components to achieve usb-if compliance through similarity, which is easy to use and provides a complete cost reduction solution. The default values of product ID, device ID and other registers may be different.
All required resistors on the USB port are integrated into the hub. This includes all series of termination resistors, as well as all required pull-down and pull-up resistors on the D + and D pins. The downstream port oriented overcurrent detection input has an internal pull-up resistance.
The usb251xb / Xbi hub series includes programmable functions, such as multitraktm Technology: a dedicated transaction converter (TT) is implemented for each port. Dedicated TTS help maintain consistent full speed data throughput regardless of the number of active downstream connections.
Portmap: provides flexible port mapping and disabling sequences. The downstream ports of the usb251xb / Xbi hub can be reordered or disabled in any order to support multiple platform designs with minimal effort. For any disabled port, the usb251xb / Xbi hub controller will automatically reorder the remaining ports to match the port numbering scheme of the USB host controller.
Portswap: allows the USB signal (D + / D -) to be directly aligned to the connector to avoid uneven tracking length or USB differential signal crossing on the PCB. Phyboost: realize four programmable levels of USB signal driving strength in the downstream port transceiver. Phyboost will also try to restore the integrity of the USB signal.
features
The smscusb251xb / Xbi hub controller provides a default configuration that may be suitable for most applications. The bundle option pin (see section 3.3.1 on page 22) provides additional functionality to enhance the default configuration.
In the default configuration, when the hub is initialized, the following functions can be configured using the bundling option:
Downstream non removable ports where hubs will automatically report as composite devices
Disable downstream ports enable the battery charging option on each port
The usb251xb / Xbi hub controller can also be configured as an SMBus slave by an external i2ceeprom or microcontroller.
When the hub is configured by i2ceeprom or above SMBus, the following configurable functions will be provided:
Port based support for composite devices
Overcurrent sensing and port power control can be selected individually or in combination to match the selection of circuit board components
Customizable supplier ID, product ID and device ID
Configurable USB signal driving strength
Configurable USB differential pair pin position
Configurable delay time for filtering overcurrent detection input
Configurable downstream port power up time reported to the host
Indicates the maximum current consumed by the hub from the USB upstream port
Indication of the maximum current required by the hub controller
Custom string descriptor (up to 31 characters):
Product manufacturer serial number
Battery charging usb251xb / Xbi products are fully compatible with usb251x / Xi / XA / Xai
Product: pin compatible direct plug-in replacement
Use the same PCB components to achieve usb-if compliance through similarity, which is easy to use and provides a complete cost reduction solution. The default values of product ID, device ID and other registers may be different.