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PXA3xx Design Guide - Marvell

PXA3xx Design Guide - Marvell

PXA3xx Design Guide - Marvell

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Figure 73: <strong>PXA3xx</strong> Processor Family Host 3 Connections to External USB TransceiverUSB HostController123Transmit enableUSB_P3_4VMOVPOSPEEDD-D+USB_P3_6OE_nMust pullHigh or Low*RCVVPUSB_P3_2USB_P3_1VM<strong>PXA3xx</strong> ProcessorUSB_P3_5USB_P3_3External USBTransceiverNoteThe “SPEED” signal does not exist for <strong>PXA3xx</strong> processor family host Port 3. The“SPEED” signal of the external device must be tied high or low. Program <strong>PXA3xx</strong>processor family host 3 to match the external device speed.20.4 Layout NotesThe USB power supply must be +5.0 V (per the USB specification). However, the <strong>PXA3xx</strong> processorfamily does not have 5.0 V-tolerant inputs. Provide an external device to interface the USBHPENxand USBHPWR pins to the power supply and over current detection circuits.NoteThere is no USBHPWR2 input signal/function on the <strong>PXA3xx</strong> processor family. Use anexternal circuit to OR the overcurrent for port 2 back into USBPWR1The C P and R S components are required by the USB host controller for USBH1_P, USBOTG_P,USBH1_N, and USBOTG_N signal compliance with the USB specification and must be placed asclose as possible to the Monahans USBH1_P, USBOTG_P, USBH1_N, and USBOTG_N balls.The R P pulldown resistors shown on the USBH1_P, USBOTG_P, USBH1_N, and USBOTG_Nsignals are required per USB specification.Terminations and filtering for signal integrity and electrostatic discharge (ESD) protection circuitryare recommended, but varies for different systems depending upon layout and end applicationenvironment.Copyright © 2009 <strong>Marvell</strong>Doc. No. MV-S301368-00 Rev. AApril 6, 2009, Released Page 169

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