Ultrasonic probe and ultrasonic diagnostic apparatus for image noise reduction by switching noise of the switching power supply to transmission
An ultrasonic probe includes: a plurality of transducers that perform electro-acoustic conversion on transmission pulses applied thereto to generate a transmission beam of ultrasonic waves; and transmission/reception circuits that are provided so as to correspond to each of the plurality of transducers. The transmission/reception circuits set transmission/reception switching timings at which the ultrasonic waves are switched from transmission to reception independently for each of the plurality of transducers.
1. An ultrasonic probe comprising:
a plurality of transducer channels that perform electro-acoustic conversion of transmission pulses applied thereto to generate a transmission beam of transmission beam ultrasonic waves;
a plurality of transmission/reception circuits respectively corresponding to each of the plurality of transducer channels, each transmission/reception circuit including a compare match timer (CMT) and a register coupled to the CMT as a transmission/reception switching timing setting circuit; and
a clock gating cell providing gated clock to the CMT; and
a port that sets the output high when the CMT matches with a value on the register,
wherein the transmission/reception switching timing setting circuits set transmission/reception switching timings at which the plurality of transducer channels are switched from transmission to reception independently,
wherein upon switching the transducer channels from transmission to reception, transmission/reception switching noises having ultrasonic waves are generated from the plurality of transducer channels,
wherein the transmission/reception switching timing setting circuits set the transmission/reception switching timings at which the plurality of transducer channels are switched such that respective focusing directions of the ultrasonic waves of the transmission/reception switching noises generated when switching the plurality of transducer channels from transmission to reception are random directions instead of focusing on a point, and
wherein the switching is delayed by a random cycle for each transducer channel by transmission/reception switching timing data written to each register of each channel.
2. The ultrasonic probe according to claim 1 ,
wherein the transmission/reception switching timing setting circuits set the transmission/reception switching timings at which the transducer channels are switched such that respective focusing directions of the ultrasonic waves of the transmission/reception switching noises generated when switching the transducer channels from transmission to reception deviate from a main lobe direction of the transmission beam of the ultrasonic waves by a predetermined angle.
3. The ultrasonic probe according to claim 1 , wherein each transmission/reception switching timing setting circuit includes:
a timer circuit that is connected to the register,
the timer circuit performing a transition from the transmission to the reception by performing a delay by a time corresponding to the transmission/reception switching timing data written to the respective register using a switching trigger from the transmission to the reception common to all the transducer channels as a starting point.
4. The ultrasonic probe according to claim 3 ,
wherein the register is a non-volatile memory.
5. An ultrasonic diagnostic apparatus comprising:
an ultrasonic probe that includes:
a plurality of transducer channels that perform electro-acoustic conversion of transmission pulses applied thereto to form a transmission beam,
a plurality of transmission/reception circuits respectively corresponding to each of the plurality of transducer channels, each transmission/reception circuit including a compare match timer (CMT) and a register coupled to the CMT as a transmission/reception switching timing setting circuit; and
a clock gating cell providing gated clock to the CMT; and
a port that sets the output high when the CMT matches with a value on the register,
an addition circuit that adds outputs of the plurality of transmission/reception circuits, and
a control circuit that controls the transmission/reception switching timings; and
a main body device that receives an output of the addition circuit and transmits a predetermined control signal to the control circuit,
wherein the transmission/reception switching timing setting circuits set transmission/reception switching timings at which the plurality of transducer channels are switched from transmission to reception independently,
wherein upon switching the transducer channels from transmission to reception, transmission/reception switching noises having ultrasonic waves are generated from the plurality of transducer channels,
wherein the control circuit controls the transmission/reception switching timing setting circuits to set the transmission/reception switching timings at which the plurality of transducer channels are switched such that respective focusing directions of the ultrasonic waves of the transmission/reception switching noises generated when switching the plurality of transducer channels from transmission to reception are random directions instead of focusing on a point, and
wherein the switching is delayed by a random cycle for each transducer channel by transmission/reception switching timing data written to each register of each channel.
6. The ultrasonic diagnostic apparatus according to claim 5 ,
wherein the control circuit controls the transmission/reception switching timing setting circuits to set the transmission/reception switching timings at which the transducer channels are switched such that respective focusing directions of the ultrasonic waves by transmission/reception switching noises generated when switching the transducer channels from the transmission to the reception deviate from a main lobe direction of the transmission beam of the ultrasonic waves by a predetermined angle.
7. The ultrasonic diagnostic apparatus according to claim 5 ,
wherein each the transmission/reception switching timing setting circuit includes:
a timer circuit that is connected to the register, and wherein the control circuit controls the transmission/reception switching timing setting circuits to perform a transition from the transmission to the reception by performing a delay by a time corresponding to the transmission/reception switching timing data written to the respective register using a switching trigger from the transmission to the reception common to all the transducer channels as a starting point.
8. The ultrasonic diagnostic apparatus according to claim 7 , wherein the register is a non-volatile memory.
9. The ultrasonic probe according to claim 1 , further comprising:
a linear feedback shift register (LFSR);
a multiplexer coupled to the LFSR;
a port coupled to the multiplexer; and
a digital signal processor coupled to the LFSR,
wherein the transmission/reception switching timing data is generated by adding a delay profile to one of pseudo-random data from the LFSR and random data input via the port by the digital signal processor, the transmission/reception switching timing data being sequentially written to each register of each channel.
10. The ultrasonic diagnostic apparatus according to claim 5 , further comprising:
a linear feedback shift register (LFSR);
a multiplexer coupled to the LFSR;
a port coupled to the multiplexer; and
a digital signal processor coupled to the LFSR,
wherein the transmission/reception switching timing data is generated by adding a delay profile to one of pseudo-random data from the LFSR and random data input via the port by the digital signal processor, the transmission/reception switching timing data being sequentially written to each register of each channel.