Maxim Integrated’s flow meter solution lasts up to 20 years on a single battery



MAXREFDES70# ultrasonic flow meter reference design

Utilities can now improve water- and heat-metering accuracy by an order of magnitude, while operating for up to 20 years on a single “A”-size battery with the MAXREFDES70# ultrasonic flow meter reference design from Maxim Integrated.

Traditional mechanical flow meters measure water and heat usage with spinning wheels that easily get out of calibration due to wear from friction and contaminants. This causes inaccurate meter readings and repeated, expensive on-site maintenance costs. Not only do these inaccurate readings reduce revenue, they also prevent leak detection, potentially wasting millions of gallons of clean water a year. The MAXREFDES70# ultrasonic flow meter is the modern alternative to that old technology. This solid-state meter is 10x more accurate that mechanical meters, and 4x more accurate than competitive ultrasonic solutions.

This accurate measurement is done without the use of heavy batteries, and the flow meter uses a single “A”-size battery that can last up to 20 years. Measuring as little as 0.5 liters of water per minute with better than 1% accuracy, its fast ultrasonic pulses can be customized to the pulse frequencies required by flow conditions. It can detect even minor leaks t hat the mechanical meters will never find. With no moving parts, the MAXREFDES70# flow meter is highly resistant to contaminants, subject to less wear, and requires virtually no maintenance. It features no compromises, as it maximizes uptime and provides the most accurate data possible. In this era when natural resource consumption must be carefully managed, this complete, ready-to-use flow meter reference design lets utilities and other industrial flow-measurement applications get to market quickly with the necessary accuracy and precision.

At the heart of the MAXREFDES70# reference design is the new MAX35101, a complete time-to-digital converter with analog front-end (AFE) that measures the difference of upstream and downstream ultrasonic pulses. Supporting flow measurement at low rates (< 30 l/hr), the MAX35101 claims the highest time-to-digital conversion accuracy (20ps) on the market today.

Key Advantages
Improved low-flow accuracy: time-to-digital accuracy of 20ps (4x better than competitive ultrasonic designs) with early edge detect and multihit capability.
Easy to implement: free schematics, layout files, and firmware are available for immediate use and customization; an evaluation (EV) kit with the MAXREFDES70# board, transducers, and USB interface is available with evaluation software.
Low power: uses one “A”-size battery running with 4Ahr capacity, and provides up to 20 years of battery operation.
High integration: integrates a complete, high-speed time-to-digital converter (MAX35101) with 4ps resolution; an AFE sends and receives the pulses for external transducers.

“With climate change concerns, pervasive droughts, and high energy prices, nearly everyone is looking for ways to conserve resources and cut costs,” said Christine Hertzog, Managing Director at Smart Grid Library. “Accurately measuring water use is a step in the right direction to intelligently manage consumption and start making water systems truly Smart Infrastructure.”

“Maxim is bringing the benefits of solid-state technology to flow measurement,” said Don Folkes, Executive Business Manager, Maxim Integrated. “To make sure the world can take advantage of this technology, we are giving our customers a solid reference design in a complete hardware, firmware, and documentation package. Now they can get a smart, more precise, ultrasonic flow meter to the market quickly.”

The MAXREFDES70# system, including circuit board with the MAX35101, two RTD probes, and spool body, is available for $500 each. The schematics, layout files, and firmware are free and available for immediate use. At electronica 2014, the MAXREFDES70# reference design will showcase Maxim’s low flow accuracy versus a traditional mechanical meter.

Visit Maxim at electronica 2014 in Munich, Germany from November 11-14. Maxim will be located in hall A4, stand 266.

electronica 2014

Maxim Integrated