Abstract: An ultrasonic flowmeter using ultrasonic pulses transmitted within a pipe containing flowing fluid determines values, including flow rate or fluid velocity of the flowing fluid. The ultrasonic flowmeter transmits trains of ultrasonic pulses having velocity components either in the upstream or downstream direction. The ultrasonic flowmeter includes the transducer placed downstream external to the pipe and a transducer placed upstream external to the pipe. Time measurements are made to determine a time, TU, required for a pulse train to travel from the downstream transducer to the upstream transducer and the time, TD, required for a pulse train to travel from the upstream transducer to the downstream transducer. The ultrasonic flowmeter is configured to have consistent triggering of the pulses of the pulse train to reduce error. Also, the electronics are simplified to allow for lower timing resolution requirements.

Abstract: An output driver that includes a waveform detector and a driver unit. The waveform detector receives at least one data signal, detects for particular patterns of interest (e.g., a sequence of zeros or ones) within the received data signal, and provides one or more control signals indicative of the detected patterns of interest. The driver unit receives the data signal and provides at least one output signal in response thereto. The driver unit further receives the control signal(s) and adjusts one or more characteristics of the output signal based on the received control signal(s). Various characteristics of the output signal (e.g., slew rate, delay, drive strength, and others) can be adjusted to achieved the desired result (e.g., reduced amount of skew, ISI). The driver unit can be designed to include a pre-driver that receives the data signal and provides at least one pre-drive signal and a driver that receives the pre-drive signal and provides the output signal.

Abstract: An ultrasonic flowmeter using ultrasonic pulses transmitted within a pipe containing flowing fluid determines values, including flow rate or fluid velocity of the flowing fluid. The ultrasonic flowmeter transmits trains of ultrasonic pulses having velocity components either in the upstream or downstream direction. The ultrasonic flowmeter includes the transducer placed downstream external to the pipe and a transducer placed upstream external to the pipe. Time measurements are made to determine a time, T.sub.U, required for a pulse train to travel from the downstream transducer to the upstream transducer and the time, T.sub.D, required for a pulse train to travel from the upstream transducer to the downstream transducer. The ultrasonic flowmeter is configured to have consistent triggering of the pulses of the pulse train to reduce error. Also, the electronics are simplified to allow for lower timing resolution requirements. Once T.sub.U and T.sub.