Texas Instruments Stellaris RDK-IDM-SBC, User Manual

Hardware Description

16

November 28, 2011

Power Supplies

The RDK-SBC has a wide input range switching-power supply that creates a 5V 1A rail for board 
operation.   The LM22672 step-down regulator switches at 500KHz with an efficiency of greater 
than 90%. Board functions require only about 150 mA with the remaining capability available for 
external interfaces such as USB host.

A low drop-out (LDO) regulator (U7) converts the +5V power rail to +3.3V to power digital devices 
including the microcontroller and SDRAM. 

USB

The LM3S9B92’s full-speed USB controller is configured for Host mode, allowing the SBC to 
connect directly to USB Flash sticks and other USB devices.

U9, a fault-protected switch, controls and monitors power to the USB host port. USB_EPEN, the 
control signal from the microcontroller, has a pull-down resistor to ensure host-port power remains 
off during reset. The power switch will immediately cut power if the attached USB device draws 
more than 1 Amp, or if the switches’ thermal limits are exceeded by a device drawing more than 
500mA. USB_PFLT indicates the over-current status back to the microcontroller.

Ethernet

With its fully integrated 10/100 Ethernet MAC and PHY, the LM3S9B92 requires only a standard 
Jack with integrated magnetics and a few passive components. The TX and RX signals are routed 
to the jack as a differential pair. The PHY incorporates MDI/MDI-X cross-over, so the function of 
the TX and RX pairs can be swapped in software. 

The Ethernet jack incorporates two status LEDs that can be controlled directly by the Ethernet 
PHY or by those same pins in GPIO mode. 

Color QVGA LCD Touch Panel

The IDM-SBC features a TFT Liquid Crystal graphics panel with 320 x 240 pixel resolution. The 
face of the panel is protected during shipping by a thin, protective plastic film which should be 
removed before use. 

The panel should be laid on a flat surface during evaluation, to protect it from damage and 
maximize the sensitivity of the touch screen.    

Features

Features of the LCD Panel include:

–

Kitronix K350QVG-V1-F display

–

320 x RGB x 240 dots

–

3.5” 262K colors

–

Wide temperature

–

White LED backlight

–

Integrated RAM

–

Resistive touch panel