Service manual

GE MEDICAL SYSTEMS PROPRIETARY TO GE
D
IRECTION , REVISION
5-20 Section 5-6 - Circuit Boards Descriptions
• Operation Description
- Scan Mode:
This mode is for imaging. The parameters specific to scan line number are sent to OQCARD’s
and the start trigger for receiving signals is generated.
- Access Mode:
This mode is for accessing SRAM memories and OQCARD’s.
5-6-2 Mid Processors
5-6-2-1 FEC
Overview
Key Features
• CHAF:(SPARE)
Three CHAFs have functions of coded excitation decorder and 2nd harmonic filter.
•COMSO:
Has functions of detector, B/M mode edge enhance, Log compression, and dynamic range control.
Figure 5-16 FEC Board
Memory/
Boot code
Line
Mem
Clock
Generation
ECL
Beamsum
Analo g
Curve ctl
Data
interface
control
EUSC
interface
COMSO
I960 PCI
Bridge
SH4 for
scan
control
SDRAM
FLASH
i960
Local Bus
SH
Local
Bus
Sec PCI
SH PCI
18
I/Q data
PGC Signal
CLK Signal
to DBF & TXB
USC BUS
RF Data
from DBF
IIC BUS
DC Voltage
Monitoring
LV Supply o/ps
HV Supply o/ps
PCI Bus