Automotive SoC targets precision ultrasonic sensing

maximmaxq7667Sunnyvale, Calif. — Maxim Integrated Products has extended its MAXQ RISC microcontroller product line with the launch of the MAXQ7667 system-on-chip (SoC), mixed-signal microcontroller for ultrasonic sensor applications. A highly integrated data-acquisition system (DAS), this SoC is said to provide a cost-effective solution for applications that must measure weak signals over long distances or identify multiple targets.

The integrated functions of the MAXQ7667 allow designers to add intelligence to cost-sensitive sensor-conditioning applications, said Maxim. The SoC is optimized for automotive-sensor systems such as electronic parking assist (EPA) and park-distance control (PDC), but it is also well suited for industrial processing, automation, and handheld applications requiring position measurement.

This 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, said Maxim.

The MAXQ7667, which measures 7 x 7 mm, 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, said Maxim.

The echo receive path includes a variable gain amplifier, a 16-bit sigma-delta ADC, a digital bandpass filter to eliminate out-of-band noise (OOB), and a digital demodulator with low-pass 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, said Maxim.

The integrated 16-bit, 16-MIPS microcontroller supports 32 KB of flash, 4 KB of data RAM, and 8 KB 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.

Other 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 48-pin LQFP package. The operating temperature range is -40°C to +125°C.

Prices: Start at $8.00 (1000-up, FOB USA). An evaluation kit is available, which includes an evaluation board and a PC-based integrated development environment (IDE) with a debugger, assembler/linker, time-limited version of the IAR C-compiler, and simulator.
Resources: MAXQ products and MAXQ7667 datasheet.