Front End - GE LOGIQ 5 PRO Service Manual

GE M S
EDICAL YSTEMS
D 2380207, R
IRECTION EVISION
Section 5-4

Front End

The Front End generates the strong burst transmitted by the probes as ultrasound into the body. It also
receives weak ultrasound echoes from blood cells and body structure, amplifies these signals and
converts them to an digital signal.
The digital representation of this signal is presented to the Mid Processor section.
• RLY(Relay) : RLY Assy contains 3 connectors for probe interface and arrays of relays for switchable
connection. High voltage multiplexer provide connection between 128 signal of probe and
selectable 64 channels transmit/receive signal
• LMT (Limiter) : This has transmit/receiving switch to isolate rx signal circuit from transmit pulse.
• PMP(Preamplifier) : The preamplifier amplifies 64 echo signals. The amplified receiving signals are
sent to RDS.
• ATD (Advanced Transmit Driver) :This has 64 channel Transmit pulse generator, bipolar pulse
drivers, delay controller.
• RDS (Receiving Delay Summing) : Cascading two receiving beam formers (two RDSs) allows the
system to achieve 64ch delay summing.
• FEC (Front End Control) : FEC control scan operation and transfer the scan parameters to others
board, ATD,RDS,RLY,PMP. Proper signal processing for tissue and dop are done in FEC
• HV(High Voltage) : Generates THV and SHV for transmit pulse driver and High voltage mux.
• SIG(Signal) : Receiving echo signal from PMP is transfer to RDS through this SIG
7
DC Power
output for
FAN(15v)
LMT Board LMT Board
Figure 5-4 The Front End
Chapter 5 Components and Functions (Theory)
DC Power output for
DC Power Input
Keyboard(15V,5V)
(3.3V, 6V,-6V,
15V,-15V,5V)
Back plane Board Back plane Board
SIG Board SIG Board
LOGIQ™5 PRO S
ERVICE
AC Power Input
(110V)
for HV
M
ANUAL
5-5