System-Level Analog Diagnostics - GE LOGIQ 9 Technical Manual

GE M S
EDICAL YSTEMS
D 2294854-100, R
IRECTION
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System-Level Analog Diagnostics

• All System-Level Analog Diags: These tests may involve the entire system or, in some cases,
only a few circuit boards.
Diagnostics which may utilize the entire system are those which test various analog aspects of the
system, such as noise floor tests, loopback tests, etc.
Diagnostics which may only utilize a few circuit boards are those which test various miscellaneous
functions, such as Analog TGC generation on the RF Amplifier board.
These tests should be performed last in the confidence-building scheme. However, the order in
which they are performed, relative to each other is not important.
• TD Analog Reference Diag: Tests the generation of the two reference voltages required on each
TD board (AD_REF and VREF), and the IIC bus communication to the TD boards through the EQ.
AD_REF is simply the output of an analog reference device on each TD, while VREF is generated
on each board based on a digital value output from the EQ (this also tests some EQ functionality
missed in its board-level diagnostic). Each is measured using an IIC-connected A/D converter on
the TD.
The system setup required for this test is shown in Figure 7-28.
Probe
• Analog TGC Diag: Tests the generation of the analog TGC voltage.
The analog TGC and IIC bus communication to the RF Amplifier board, through the EQ is tested.
The RF Amplifier functionality tested includes:
-
-
The system setup required for this test is shown in Figure 7-29.
Probe
PROPRIETARY TO GE
3
EVISION
IIC
RF
RF
XDIF/RF
PCI
Host
Figure 7-28 System-Level TD Analog Reference Block Diagram
Analog TGC digital communication with EQ (this also tests some EQ functionality missed in
its board-level diagnostic) and analog TGC Gain Reference generation, through the DAC
RF Amplifier on-board IIC functionality
IIC
RF RF
XDIF/RF
PCI
Host
Figure 7-29 Analog TGC System Setup Block Diagram
Chapter 7 Diagnostics/Troubleshooting
VREF
IQ RxSYNC
TD's EQ
Scan Control Board
TGC
IQ RxSYNC
TD s EQ
Scan Control Board
LOGIQ™ 9 P
ROPRIETARY
IQ,
BM
BMP
IQ,
BM
BMP
M
ANUAL
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