Texas Instruments The Future of Robotics | 11
Figure 4: Texas Instruments PGA460/PGA460-Q1 Ultrasonic
Processor & Driver is a highly integrated system-on-chip
ultrasonic transducer driver, and a signal conditioner with an
advanced DSP core.
Figure 5: Texas Instruments TUSS4470 Direct Drive Ultrasonic
Sensor IC is a highly integrated transformer drive analog front end
for industrial ultrasonic applications.
The components of an ultrasonic-based obstruction avoidance
system used in autonomous robotic systems might include an
ultrasonic signal processor and transducer driver, such as the
Texas Instruments PGA460/PGA460-Q1 Ultrasonic Processor &
Driver, a highly integrated system-on-chip ultrasonic transducer
driver, and a signal conditioner with an advanced DSP core
(Figure 4). It drives the transformer, processes the returned
electrical signals from the echoes, and calculates the ToF data
for each of the relevant echoes in real-time. The device has a
complimentary low-side driver pair that can drive a transducer
either in a transformer-based topology using a step-up
transformer or in a direct-drive topology using external high-side
FETs. The PGA460/PGA460-Q1 can receive and condition the
reflected echo signal for reliable object detection. This feature
gets accomplished using an analog front-end (AFE) consisting of
a low-noise amplifier followed by a programmable time-varying
gain stage feeding into an ADC. The digitized signal is then
processed in the DSP core for both near-field and far-field object
detection using time-varying thresholds.
Other designs might benefit from Texas Instruments TUSS4470
Direct Drive Ultrasonic Sensor IC, a highly integrated transformer
drive analog front end for industrial ultrasonic applications
(Figure 5). The transducer drive stage is an internal H-bridge
that can be configured to drive the transducer in direct-drive
mode to achieve maximum voltage across the transducer. The
internal H-bridge can also be configured as a pre-driver for
external FETs, enabling higher current and voltage drive for
larger transducers.
