SAM3SD8C Atmel Corporation, SAM3SD8C Datasheet - Page 956

• Manufacturer Part Number: SAM3SD8C
• Manufacturer: Atmel Corporation

36.5
Figure 36-2. Board Schematic to Interface Device Peripheral
36.5.1
36.5.2
36.6
36.6.1
956
956
Typical Connection
Functional Description
SAM3S8/SD8
SAM3S8/SD8
USB Device Transceiver
VBUS Monitoring
USB V2.0 Full-speed Introduction
PIO
DDM
DDP
5V Bus Monitoring
The USB device transceiver is embedded in the product. A few discrete components are
required as follows:
VBUS monitoring is required to detect host connection. VBUS monitoring is done using a stan-
dard PIO with internal pullup disabled. When the host is switched off, it should be considered as
a disconnect, the pullup must be disabled in order to prevent powering the host through the pull-
up resistor.
When the host is disconnected and the transceiver is enabled, then DDP and DDM are floating.
This may lead to over consumption. A solution is to enable the integrated pulldown by disabling
the transceiver (TXVDIS = 1) and then remove the pullup (PUON = 0).
A termination serial resistor must be connected to DDP and DDM. The resistor value is defined
in the electrical specification of the product (R
The USB V2.0 full-speed provides communication services between host and attached USB
devices. Each device is offered with a collection of communication flows (pipes) associated with
each endpoint. Software on the host communicates with a USB device through a set of commu-
nication flows.
• the application detects all device states as defined in chapter 9 of the USB specification;
• to reduce power consumption the host is disconnected
• for line termination.
– VBUS monitoring
47 K
27 K
R
R
EXT
EXT
EXT
).
2
3
Connector
Type B
1
4
11090A–ATARM–10-Feb-12
11090A–ATARM–10-Feb-12