Tektronix AWG7000 Series Service Manual page 28

Theory of Operation
Front Switch (FSW) Board
Front Connector (FCON)
Board
Display Panel
Touch Panel
Processor (µATX) Board
Power Supply
Fans
Power (PWR) Board
2-4
The FSW board provides interconnection between the Standby switch and µATX
board. It includes an LED driver.
The FCON board provides front-panel connections of the USB ports and the DC
output. It includes common mode filters that suppress EMI radiation on the USB
signal.
The active-matrix LCD display is fully controlled by Windows drivers. It is
controlled by the ATI Mobility-M1 micro circuit on the MIO board. The display
has a 1024 x 768 resolution. Brightness is controlled by the intensity of the
backlight.
The touch information from the touch screen is processed by Windows drivers,
actively placing the pointer at the touched location. Actions from the mouse and
the touch panel are interchangeable, and treated alike by the user interface
software. The AccuTouch five-wire resistive touch screen uses a glass panel with
a uniform resistive coating. A thick polyester coversheet is tightly suspended over
the top of a glass substrate, separated by small, transparent insulating dots. The
coversheet has a hard, durable coating on the outer side and a conductive coating
on the inner side. The controller is located on the LCDA board.
The µATX board provides standard Windows functionality and I/O port interfaces
on the rear panel. This includes RS-232, Parallel, and Ethernet ports, as well as four
USB ports, including two USB2.0 ports located in the lower right front corner of
the instrument. The µATX board receives input from the front panel and touch
panel, and implements the appropriate changes. Video display data is transferred
to the MIO board through the PCI bus interface. The hard drive is connected to the
µATX board through the SATA interface, and the CD/DVD is connected to the
Windows system through the IDE parallel interface.
The power supply CVR460 is a switching AC to DC converter. It automatically
detects the line voltage over the range of 90 to 264 VAC. It supplies power to all
the circuitry in the instrument. No switch completely disconnects the line power
from the instrument. The ON/STBY switch controls the power to the instrument
through the µATX board circuitry. When in the "power off" condition, there is still
a low power standby current to allow the system to monitor the ON/STBY switch.
Three fans on the side of the instrument provide forced air cooling. The fans are
controlled by the fan speed control circuit on the PWR board and are regulated by
monitoring the temperature at the circuitry.
The PWR board provides DC power to the fans, HDD, CD Drive, µATX board,
MIO board, and AWG10G board. All the power comes from the CVR460 module.
The fan control circuit has a thermal sensor on this board. DC voltage to the fans
is controlled relative to the sensed temperature. DC-DC converters are included for
generating different DC voltages.
AWG7000 Series Service Manual