MAXQ7667 Datasheet, PDF (1/40 Pages) Maxim Integrated Products – 16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

19-4598; Rev 1; 7/09
16-Bit, RISC, Microcontroller-Based,
Ultrasonic Distance-Measuring System
General Description
The MAXQ7667 smart system-on-a-chip (SoC) provides a
time-of-flight ultrasonic distance-measuring solution. The
device is optimized for applications involving large dis-
tance measurement with weak input signals or multiple
target identification. The MAXQ7667 features high signal-
to-noise ratio achieved by combining flexible electronics
with the intelligence necessary to optimize each function
as environmental and target conditions change.
An integrated burst signal generator and echo reception
components process ultrasonic signals between 25kHz
and 100kHz. Echo reception components include a pro-
grammable gain low-noise amplifier (LNA), a 16-bit
sigma-delta ADC to digitize the received echo signals,
and digital signal processing (DSP). DSP limits noise
with a bandpass filter, and creates an echo envelope
through demodulation and lowpass filtering. Input
referred noise is a low 0.7µV_RMS. A programmable
phase-locked loop (PLL) frequency synthesizer supplies
the reference frequency for the burst generator and the
clock for the echo receiver’s digital filter. An embedded
16-bit MAXQ20 microcontroller (µC) controls all the pre-
ceding functions.
The µC optimizes the burst frequency and reception
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
available for echo optimization, communication, diag-
nostics, and additional signal processing.
The MAXQ7667 operates with three different power
supply voltages: +5V, +3.3V, and +2.5V. Two internal
linear regulators allow operation from a single +5V sup-
ply when three external power supplies are not avail-
able. Alternatively, the MAXQ7667 can control an
external pass transistor to allow operation from a single
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 -40°C to +125°C.
Applications
Automotive Parking
Vehicle Security
Industrial Processing
Automation
Handheld Devices
Features
o Smart Analog Peripherals
Dedicated Ultrasonic Burst Generator
Echo Receiving Path (Includes LNA, Sigma-
Delta ADC)
5-Channel, 12-Bit SAR ADC with 250ksps
Sampling Rate
Internal Bandgap Voltage Reference for the
ADCs (Also Accepts External Voltage Reference)
o Timer/Digital I/O Peripherals
o High-Performance, Low-Power, 16-Bit RISC Core
o Program and Data Memory
o Crystal/Clock Module
o 16 x 16 Hardware Multiplier with 48-Bit
Accumulator, Single Clock Cycle
o Power-Management Module
o JTAG Interface
o Universal Asynchronous Receiver-Transmitter
(UART)
o Local Interconnect Network (LIN)
See the Detailed Features section for complete list of features.
Ordering Information
PART
PIN-PACKAGE ^RAM
(KB)
FLASH
(KB)
MAXQ7667AACM/V+
48 LQFP
4
32
Note: All devices are specified over the -40°C to +125°C oper-
ating temperature range.
/V denotes an automotive qualified part.
+Denotes a lead(Pb)-free/RoHS-compliant package.
Pin Configuration appears at end of data sheet.
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.
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For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.