This 7mm x 7mm device integrates the main functional blocks required to accurately measure position, including burst control (pulse transmission), analog echo reception, digital signal processing, and a microcontroller. This advanced integration reduces system cost and increases sensor-mounting options.
The MAXQ7667 features a programmable burst-frequency generator to compensate for transducer tolerances, adjust frequency with temperature, and perform diagnostics. Programmable burst and duty cycles can optimize power to match environmental conditions. The echo receive path includes a variable gain amplifier, a 16-bit sigma-delta ADC, a digital bandpass filter to eliminate OOB (out-of-band noise), and a digital demodulator with lowpass filtering to create an echo envelope. Echo detection is supported by an interrupt-generating, 16-bit threshold detector with programmable threshold and hysteresis levels. The microcontroller can be used for additional signal processing, or it can act as the threshold detector.
The integrated 16-bit, 16-MIPS microcontroller supports 32KB of flash, 4KB of data RAM, and 8KB of utility ROM. The microcontroller can be programmed to dynamically optimize parameters, vary threshold based on time and noise, optimize frequency to match the transducer, and adjust power and threshold based on the location of targets. Additional features include a general-purpose ADC for diagnostics and temperature measurement, a LIN-compatible UART with address capability, three general-purpose timers with interrupt capability, a system timer, general-purpose I/O pins with interrupt capability, and single-supply operation.
The MAXQ7667 is available in a space-saving 48-pin LQFP package, and is fully supported over the –40°C to 125°C automotive temperature range. Prices start at $8.00 (1000-up, FOB USA). An evaluation kit is available to speed designs. This kit includes an evaluation board and a PC-based IDE (integrated development environment), which provides a debugger, assembler/linker, time-limited version of the IAR C-compiler, and simulator. Additionally, Maxim's website offers many application notes and software examples to use with the MAXQ family of products.
About Maxim Integrated Products
Maxim Integrated Products is a publicly traded company that designs, manufactures, and sells high-performance semiconductor products. The Company was founded over 25 years ago with the mission to deliver innovative analog and mixed-signal engineering solutions that add value to its customers' products. To date, it has developed over 6100 products serving the industrial, communications, consumer, and computing markets.
Maxim reported revenue in excess of $1.6 billion for fiscal 2009. A Fortune 1000 company, Maxim is included in the Nasdaq 100, the Russell 1000, and the MSCI USA indices.