MAXQ7667 19-4598 Rev 1 7/09 16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System General Description Features Smart Analog Peripherals The MAXQ7667 smart system-on-a-chip (SoC) provides a time-of-flight ultrasonic distance-measuring solution. The Dedicated Ultrasonic Burst Generator device is optimized for applications involving large dis- Echo Receiving Path (Includes LNA, Sigma- tance measurement with weak input signals or multiple Delta ADC) target identification. The MAXQ7667 features high signal- 5-Channel, 12-Bit SAR ADC with 250ksps to-noise ratio achieved by combining flexible electronics Sampling Rate with the intelligence necessary to optimize each function as environmental and target conditions change. Internal Bandgap Voltage Reference for the ADCs (Also Accepts External Voltage Reference) An integrated burst signal generator and echo reception Timer/Digital I/O Peripherals components process ultrasonic signals between 25kHz and 100kHz. Echo reception components include a pro- High-Performance, Low-Power, 16-Bit RISC Core grammable gain low-noise amplifier (LNA), a 16-bit Program and Data Memory sigma-delta ADC to digitize the received echo signals, Crystal/Clock Module and digital signal processing (DSP). DSP limits noise 16 x 16 Hardware Multiplier with 48-Bit with a bandpass filter, and creates an echo envelope Accumulator, Single Clock Cycle through demodulation and lowpass filtering. Input referred noise is a low 0.7V . A programmable RMS Power-Management Module phase-locked loop (PLL) frequency synthesizer supplies JTAG Interface the reference frequency for the burst generator and the Universal Asynchronous Receiver-Transmitter clock for the echo receivers digital filter. An embedded (UART) 16-bit MAXQ20 microcontroller (C) controls all the pre- ceding functions. Local Interconnect Network (LIN) The C optimizes the burst frequency and reception See the Detailed Features section for complete list of features. frequency for each transmission at any temperature. The MAXQ7667 achieves smart sensing by monitoring the echo signals and then actively changing the trans- mitted and received parameters to obtain optimum results. Digital filtering and burst synthesis do not require CPU intervention. This leaves all the CPU power Ordering Information available for echo optimization, communication, diag- nostics, and additional signal processing. RAM FLASH PART PIN-PACKAGE The MAXQ7667 operates with three different power (KB) (KB) supply voltages: +5V, +3.3V, and +2.5V. Two internal MAXQ7667AACM/V+ 48 LQFP 4 32 linear regulators allow operation from a single +5V sup- Note: All devices are specified over the -40C to +125C oper- ply when three external power supplies are not avail- ating temperature range. able. Alternatively, the MAXQ7667 can control an /V denotes an automotive qualified part. external pass transistor to allow operation from a single +Denotes a lead(Pb)-free/RoHS-compliant package. supply voltage of +8V to +65V or more, depending on the external component tolerance. The device is avail- able in a 48-pin LQFP package and is specified to operate from -40C to +125C. Pin Configuration appears at end of data sheet. Applications Automotive Parking Automation Vehicle Security Handheld Devices Industrial Processing Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device may be simultaneously available through various sales channels. For information about device errata, go to: ww.maxim-ic.com/errata. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System ABSOLUTE MAXIMUM RATINGS DVDDIO, GATE5, REG3P3, REG2P5 to Analog Inputs/Outputs to AGND............-0.3V to (V + 0.3V) AVDD DGND................................................................-0.3V to +6.0V XIN, XOUT to DGND ..............................-0.3V to (V + 0.3V) DVDD AVDD to AGND .....................................................-0.3V to +4.0V Maximum Current into Any Pin............................................50mA DVDD to DGND.....................................................-0.3V to +3.0V Continuous Power Dissipation (T = +70C) A DVDDIO to DVDD..................................................-0.3V to +6.0V 48-Pin LQFP (derate 21.7mW/C above +70C).....1739.1mW AVDD to DVDD......................................................-0.3V to +4.0V Operating Temperature Range .........................-40C to +125C AGND to DGND.....................................................-0.3V to +0.3V Storage Temperature Range .............................-60C to +150C Digital Inputs/Outputs to DGND..........-0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) .................................+300C DVDDIO Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = +5V, V = +3.3V V = +2.5V, system clock (f ) = 16MHz, burst frequency (f ) = bandpass frequency DVDDIO AVDD DVDD SYSCLK BURST (f ) = 50kHz, C = C = 1F in parallel with 0.01F, f = 2MHz (SAR data rate = 125ksps), T = T to T , unless BPF REFBG REF ADCCLK A MIN MAX otherwise specified. Typical values are at T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ECHO INPUT (Low-Noise Amplifier and Sigma-Delta ADC) VGA gain adjust = 1.55V/LSB 5.6 Input-Referred Noise P-P V RMS (Note 1) VGA gain adjust = 0.1V/LSB 0.7 P-P VGA gain adjust = 1.55V/LSB 80 P-P Minimum Detectable Signal V P-P VGA gain adjust = 0.1V/LSB 10 P-P VGA gain adjust = 1.55V /LSB, P-P 100 unclipped Operating Input Range mV P-P VGA gain adjust = 0.1V /LSB, P-P 6.7 unclipped VGA gain adjust 1.55 From echo input to = 1.55V /LSB P-P bandpass filter in Programmable Gain V /LSB P-P VGA gain adjust reply to input 0.1 = 0.1V /LSB P-P Programmable-Gain Adjust (Note 2) 10 % Resolution LNA Bandwidth 150 kHz ADC Sampling Rate 80 x f kHz BPF ADC Output Data Rate 10 x f kHz BPF ADC Output Data Resolution 16 Bits Echo-Input Resistance R For each echo input 14 k IN Echo-Input Capacitance 14 pF Echo-Input DC Bias Voltage V /2 V AVDD Maximum Overvoltage Recover from 2Vinput 10 s P-P Recovery Time 2 MAXQ7667