ATSAM3S-EK Atmel, ATSAM3S-EK Datasheet - Page 928

• Manufacturer Part Number: ATSAM3S-EK
• Description: KIT EVAL FOR ATSAM3S4C
• Manufacturer: Atmel
• Series: SAM3Sr
• Type: MCUr

Specifications of ATSAM3S-EK

• Contents: Board, Cables, Power Supply
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex-M3
• Kit Contents: Board
• Features: TFT Colour LCD Display, SD/MMC Interface
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• For Use With/related Products: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

37.5
37.5.1
37.5.2
928
Typical Connection
SAM3S Preliminary
USB Device Transceiver
VBUS Monitoring
Figure 37-2. Board Schematic to Interface Device Peripheral
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 pull-up disabled. When the host is switched off, it should be considered as
a disconnect, the pull-up 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 pull-down by disabling
the transceiver (TXVDIS = 1) and then remove the pull-up (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 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.
PIO
DDM
DDP
– VBUS monitoring
5V Bus Monitoring
47 K
27 K
R
R
EXT
EXT
EXT
).
2
3
Connector
6500C–ATARM–8-Feb-11
Type B
1
4