Time-to-Digital Converter with Analog Front-End
Accurate Low Flow Measurement with Low System Power Consumption
DescriptionThe MAX35101 is a time-to-digital converter with built-in amplifier and comparator targeted as a complete analog front-end (AFE) solution for the ultrasonic heat meter and flow meter markets.
With a time measurement accuracy of 20ps and automatic differential time-of-flight (TOF) measurement, this device makes for simplified computation of liquid flow. Early edge detection ensures measurements are made with consistent wave patterns to greatly improve accuracy and eliminate erroneous measurements.
Multihit capability with stop-enable windowing allows the device to be fine-tuned for the application. Internal analog switches, an autozero amplifier/comparator, real-time clock (RTC), and programmable receiver sensitivity provide the analog interface and control for a minimal electrical bill of material solution. The RTC provides an event timing mode that is configurable and runs cyclic algorithms to minimize microprocessor interactivity and increase battery life.
Built-in arithmetic logic unit provides TOF difference measurements. A programmable receiver hit accumulator can be utilized to minimize the host microprocessor access and thus minimize current consumption.
For temperature measurement, the MAX35101 supports up to four (4) 2-wire PT1000/500 platinum resistive temperature detectors (RTD).
A simple 4-wire SPI interface allows any microcontroller to effectively configure the device for its intended measurement.
On-board 8KB user flash allows the MAX35101 to be nonvolatile-configurable and provide nonvolatile energy use data to be logged. Configuration can be recalled anytime with a SPI command.
- High Accuracy Flow Measurement for Billing and Leak Detection
- Time-to-Digital Accuracy Down to 20ps
- Measurement Range Up to 8ms
- Two Channels: Single-Stop Channel
- High Accuracy Temperature Measurement for Precise Heat and Flow Calculations
- Up to Four (4) 2-Wire Sensors
- PT1000 and PT500 RTD Support
- Maximizes Battery Life with Low Device and Overall System Power
- Low 10µA ToF measurement and < 125nA Duty-Cycled Temperature Measurement
- Event Timing Mode Reduces Host µC
- Overhead to Minimize System Power Consumption
- 2.3V to 3.6V Single-Supply Operation
- High-Integration Solution Minimizes Parts Countand Reduces BOM Cost
- 8KB of Nonvolatile Flash Memory for Data Logging
- Built-in Real Time Clock
- Small, 5mm x 5mm, 32-Pin TQFP Package
- -40°C to +85°C Operation
- Ultrasonic Gas Meters
- Ultrasonic Heat Meters
- Ultrasonic Water Meters
|Part Number||Sensing Element||PGA Gain||Calibration Method||Output Type||ICC|
|MAX35101||Ultrasonic Piezoelectric Transducer||Fixed||External microcontroller||Digital||0.01||SPI||2.3 to 3.6|
Technical DocumentsApp Note 6226 Let Them Drink Beer, or Try Ultrasonic Meters
App Note 6107 Using the MAX35101 in a Heat Meter Application
App Note 6106 MAX35101, MAX35102, MAX35103 Frequently Asked Questions
App Note 6105 Configuring the MAX35101 Time-to-Digital Converter as an Ultrasonic Water Meter
App Note 6104 Calibration of Water Flow Rate in an Ultrasonic Flow Meter Using the MAX35101
App Note 5968 Welcoming Water Metering into the 21st Century
App Note 5887 The Sure Evolution of Static "Smart Home" Water Metering
App Note 5832 Water and Power in the Internet of Everything
App Note 5809 Simulation and Correlation of Flow-Rate Measurement in an Ultrasonic Time-of-Flight Heat Meter
|Device||Fab Process||Technology||Sample size||Rejects||FIT at 25°C||FIT at 55°C||Material Composition|
|App Note||6226||Let Them Drink Beer, or Try Ultrasonic Meters|
|App Note||6107||Using the MAX35101 in a Heat Meter Application|
|App Note||6106||MAX35101, MAX35102, MAX35103 Frequently Asked Questions|
|App Note||6105||Configuring the MAX35101 Time-to-Digital Converter as an Ultrasonic Water Meter|
|App Note||6104||Calibration of Water Flow Rate in an Ultrasonic Flow Meter Using the MAX35101|
|App Note||5968||Welcoming Water Metering into the 21st Century|
|App Note||5887||The Sure Evolution of Static "Smart Home" Water Metering|
|App Note||5832||Water and Power in the Internet of Everything|
|App Note||5809||Simulation and Correlation of Flow-Rate Measurement in an Ultrasonic Time-of-Flight Heat Meter|