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www.pericom.com

P-0.1

07/12/13

PI5USB1458

Detailed Feature Description

Auto Dedicated Charging Mode enabled

When the PI5USB1458 (/A) is configured into auto mode with Auto dedicated charging mode enabled (see truth table to under-

stand how to configure into auto mode), the charger controller will manage all communication with external devices to enable

charging to occur. First, Pericom’s IC will use load sensing techniques to detect when a device has been plugged in.

Once a device is properly detected, the Pericom IC will automatically switch to the appropriate charging mode required for the

specific external USB device that was detected.

Mouse/Keyboard pass through mode Explanation

Today’s systems are enabled to wake up from S3 mode if a pre-enumerated mouse/keyboard has activity (movement or key-pressed).

In order for the system to continue supporting this feature, the USB host controller must be able to communicate with the external

device in S3 mode. Therefore, if a mouse/keyboard is detected (via the USB low-speed/ full-speed pass through feature), Pericom’s

PI5USB1458 family will enable the communication between device and controller. Our device will automatically pass the signals

through with minimal degradation.

Once SB/ signal goes from high to low (indicating system has changed from S0 to S3), Pericom's device will detect the external USB

device. If the device is detected as a mouse or keyboard (determined by looking at USB data-rate) we will ensure the connection

between the USB device and USB host remains in place.

Anti-Loop protection for HDD

This circuit prevents hard disk drive from turning on and off continously.

Auto Dedicated Charger mode description

During Pericom's Auto dedicated charger mode, we automatically detect and enable DCP charging modes for all popular USB

devices on the market.

DCP stands for Dedicated Charging Port. Per the Battery Charging Spec, DCP is described as a host charging mode whereas only

charging is allowed. Data transfer through USB, during DCP mode is not allowed. Per the Battery Charging Spec, the host charger

must short D+ to D-, and in turn the USB device will draw up to 1.5A.

Since the release of the Battery Charging Spec, certain mobile phone and tablet OEMs have released products with unique dedicated

charging modes. When Pericom's Auto dedicated charger mode is enabled, we can automatically switch between dedicated charging

modes per the Battery charging spec or other dedicated charging modes supported by specific OEMs.

CDP mode description

Charging Downstream Port (CDP) is the communication protocol found in host chargers capable of supplying up to 1.5A current to

charge external USB devices. The communication scheme is defined clearly in the USB Battery Charging Spec 1.2. A CDP link can

allow USB data to be transferred between the host charger and the external device as well as allow charging to occur. The actual

current draw is managed by the external device while the CDP only limits the max current draw to 1.5A. Pericom is able to fully

support this communication, which includes both a primary and secondary detection procedure.

BC 1.2 Suspend Charging (DCP)

The suspend-charge (DCP) mode defined in BC 1.2 is a manual-DCP-mode, is not exactly the same as the auto suspend-charge

mode in PI5USB1458. In order to offer an accurate BC 1.2 suspend-charge (DCP) mode apply: "SB/" to 1 and “SEL” pin with 1.25V,

Power-off, then after re-power-on PI5USB1458/A.

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