Ultrasonic Flow Converters

AS6031 Ultrasonic Flow Converter

AS6031 is an ultrasonic flow converter for the next generation of ultrasonic water and heat meters. It is highly integrated and is based on the TDC-GP30 platform. It uses the same high-performant front-end for driving the transducers and processing the receive signal to extract the time of flight information. An additional programmable amplifier allows handling weaker receive amplitudes. Additional features for phase-modulated hit identification give even more robustness to the first hit level detection. The integrated low-power CPU can use 4k of NVRAM and 4k of ROM code to do the flow calculation on chip.

AS6031 simplifies the design of ultrasonic water and heat meters, combining the precise measurement and the complex flow calculation. It provides outstanding low-flow detection capability due to excellent zero-flow drift. Users can apply any of-the-shelf μP for handling all other tasks like display management or wireless communication and a complete meter device. The integrated standard pulse interface enables one-to-one replacement of mechanical meters by AS6031 based single-chip heat and water meters – customer μP and software remains unchanged.

The ultra-low-current capabilities allow the use of standard AA batteries at 6-8 Hz measuring frequency even in the water meter version. The chip comes in a compact QFN48 package and allows compact designs thanks to a small number of external components.

Product Status: In production

Download Datasheet Dashboard Software

Features

High performance + ultra-low power 32-Bit CPU
120 * 32 bit NVRAM (non-volatile RAM) for user firmware parameter & data
3968 * 8 bit NVRAM (non-volatile RAM) for user firmware program code
4k * 8 bit ROM for system task code and special flow library code
Advanced high-precision analog front-end for transducer frequencies of 50 kHz to 4 MHz at 2.5 V to 3.6 V drive voltage
Integrated PGA, gain 2 to 30 @ 1 MHz
First hit level and phase detection
Amplitude measurement
Up to 31 zero crossing measurements
Precision time-to-digital converter and low-noise front-end with < 50 ps single shot with good 1MHz transducers on a DN20
Ultra-low power consumption
SPI serial interface
General Purpose I/O Unit incl. pulse interface and 2-wire master interface (I2C like)
Supply voltage 2.5 to 3.6 V
3.0 to 3.6 V NVRAM store only
Operating temperature -40 to 85°C
QFN48 package (7 x 7mm²)

Benefits

Single-chip solution provided ready flow information
System design compatible with mechanical meters
High flexibility in choice for external μP handling communication and further data management
Precision down to low flow rates
Leakage detection
Handles weak signals for small transducers and multiple reflections
Compact design
Low BOM

Product properties

Analog Frontend

Yes, with PGA

First Wave Detection

Yes, Split burst

Amplitude Measurement

Yes

Number of Hits

Resolution TDC [ps]

Operating Supply Range

2.5 to 3.6

Interface