8
BD4000/BD4002 Transducers
8.1
US1 Ultrasound Transducer
Timing Logic
, is driven by the control and carrier signals fed from the main unit.
This logic controls the transmitter and receiver range gating.
5V Regulator
, the 5V regulator is supplied from the +10V line.
Range Gate Control
, is used to reject any unwanted signal caused by reflections and
contact noise.
Transmitter Output
, the output is pulsed, the timing of which is controlled by the
timing logic section.
Range Gate Switching
, the signal from the ultrasound head is selected by the range
gating section to ensure that the receiver circuitry is not enabled during the transmit
period, this is switched on after a suitable period to reduce unwanted signals.
Demodulator
, a reference signal from the main oscillator is used to demodulate the
received signal.
Filter Network
, the output from the demodulator is low pass filtered to remove any
unwanted noise.
Output Buffers
, to minimise noise, a balanced output is used.
Ultrasound Faceplate
, comprises a multi element array with 7 crystals connected in
parallel.
Issue: 2 DRAFT
33
Rev: a
614365
