The TDC-GP30 is the next generation of ultrasonic flow converters. Besides an improved analog time-of-flight front end, it also includes a 32-bit CPU and memory for on-chip data post-processing and the complete flow calculation. This highly sophisticated circuit has been designed for use as a stand-alone component single-chip replacement for mechanical flow meters - using a pulse output, and as a two-chip solution (GP30 + external microcontroller) for applications requiring other interfaces – such as wireless flowmeters, LCD based meters, or similar. With the powerful built-in CPU and specialized ROM-based firmware, the GP30 can be used for many types of ultrasonic heat and water meters. It includes all flow and temperature measurement calculations internally, plus allows for highly customized configurations using customer-defined firmware routines and the internal CPU.
Because of the high-resolution of the internal time-to-digital converter and front-end ability to measure signal amplitudes, the GP30 can detect very low flows - aka leaks - down to 0.5 liter/hour or better in quiet systems, and detect anomalies in the flow, such as air bubbles, empty spool pieces, or aging of the spool piece. These are unique qualities of the GP30 not found in other solutions.
The GP30 is designed for driving external ultrasonic transducers and can
be configured for extremely low power, making battery operated flow
meters a reality, for example, 6 μA at 8 Hz, including flow and
temperature calculations.
Key features are shown in the block diagram below also include:
The GP30 SOC is available as QFN32 or QFN40 package, with the QFN40
package able to manage an external circuit for gas meters or larger
diameter pipes needing boosted signal levels.
The GP30 is designed for autonomous operation. In self -controlled flow
meter mode it triggers all measurements and does data processing to
deliver flow information, independent of external control. It can also
be configured to wake up an external microcontroller for communication
of results. Operation in this mode utilizes the internal 32-bit CPU and
embedded firmware. The firmware code memory and the firmware data memory
are zero static power NVRAMs. Since they don’t draw current when not in
use, they are not switched down and remain permanently usable.
Innovative companies are using the GP30 to further the development of
smart systems that can very accurately measure the amount of water
delivered to specific zones, measure the viscosity of fluids, measure
gas flow, and other unique applications where ultrasonic techniques can
be leveraged to replace older mechanical mechanisms. As more IoT
applications become not only technically feasible but also financially
and environmentally necessary, the GP30 will be able to lead the way to
cost-effective battery-operated solutions.