The Application of TDC-GP21 in Ultrasonic Heat Meter

TDC-GP21 is an enhancement to the TDC-GP2. The GP21 has added some new features for extended functionality and improvements over the existing GP2.

Enhancements include: analog front end, pin-to-pin compatibility (for existing designs), analog stabilized comparator and simplified external circuit design, improved time and temperature measurement and reduced current.

TDC-GP21 is perfectly suited to design compact and low cost ultrasonic flow meters and heat meters. The enhanced analog front end allows a reduction in the number of external components.

Using integrated analog elements of the TDC-GP21, the average operating current of a typical ultrasonic flow meter application can be reduced to 2.2 μA.

TDC-GP21 has a high accuracy level of time measurement function, the resolution can reach 22ps, provided the basic measure safeguard for the application of the time difference flowmeter. TDC-GP21 pulse generator in small diameter flow measurement can directly drive ultrasonic transducer, and there is no need for additional drive chip. The low power consumption of TDC-GP21 measurement makes the whole flow properties sharply reduced, providing superior solutions for battery power supply equipment.

Using the TDC-GP21 ultrasonic flowmeter, relatively to use division scheme of components or FPGA ultrasonic flow meter case, greatly simplified the hardware circuit design, it only needs to match low power consumption MCU, plus a few resistance and capacitance can complete control and time measurement circuit design. The scheme simplified the circuit design and greatly reduced the equipmen PCB area, which also made production and maintenance more convenient. TDC-GP21 with two road temperature measurement function can be directly connected with PT1000 or PT500 hot resistance to have temperature measurement, which provided integrated solutions to heat meter application.