/a>Sensor” title=”Sensor”>Sensor” title=”Sensor”>Sensor interface device, integrated voltage regulator, 12-bit SAR ADC, 8-bit microcontroller, digital bandpass filter, DAC, two NMOS low-side driver, low noise amplifier, oscillator, LIN 2.1 physical interface protocol interface. Mainly used for car parking, blind spot detection and object detection. This article introduces the main features of PGA450-Q1, functional block diagram, application circuit diagram, evaluation board PGA450-Q1 EVM main features, circuit diagram and PCB layout.
The PGA450-Q1 is a fully integrated interface device for ultrasonic transducers used in automotive park distance or object detection applications. It incorporates these system blocks: voltage regulators, a 12-bit SAR ADC, an 8-bit microcontroller, a digital band-pass filter, a DAC, dual NMOS low-side drivers, a low-noise amplifier, an oscillator, and a LIN 2.1 physical interface and protocol for interfacing.
The PGA450-Q1 possesses an 8-bit microcontroller and OTP memory for program storage for processing the echo signal and calculating the distance between the transducer and the object. This data is transmitted through the LIN 2.1 communication protocol. The LIN 2.1 physical layer is slave -only and does not implement the LIN wake-up feature.
PGA450-Q1 main features:
Dual NMOS Low-Side Drivers
Configurable Burst Generator
Low-Noise Amplifier
12-Bit SAR ADC
Configurable Digital Band-Pass Filter
Digital Signal Envelope Detect
On-Chip 8-Bit Microprocessor
LIN 2.1 Physical Interface and Protocol
Watchdog Timer
Four-Wire SPI for Testability / Programming
8K Bytes OTP
768 Bytes of FIFO RAM
256 Bytes Scratchpad RAM
8K Bytes of Development RAM
32 Bytes of EEPROM for Application
PGA450-Q1 Application:
Automotive Park Distance
Blind Spot Detection
Object Detection Applications
Figure 1. PGA450-Q1 functional block diagram
The digital data path has the following components:
• Band-pass filter
• Rectifier
• Peak extractor
• Downsampler
• Low-pass filter
Figure 2. PGA450-Q1 Digital Datapath Block Diagram
Figure 3. PGA450-Q1 application circuit diagram
Evaluation Board PGA450-Q1 EVM
This user’s guide describes the characteristics, operation, and use of the PGA450-Q1 EVM.
Main features of the evaluation board PGA450-Q1 EVM:
• Single power-supply input for basic operation
• Example single-ended transformer and 58-kHz transducer
• LIN master transceiver
• RS-232 transceiver for UART testing and debug
• PC control with a graphical user interface and USB communications board
Figure 4. Evaluation Board PGA450-Q1 EVM Outline Drawing
Figure 5. Evaluation Board PGA450-Q1 EVM Circuit Diagram: LIN
Figure 6. Evaluation Board PGA450-Q1 EVM Circuit Diagram: Power
Figure 7. Evaluation Board PGA450-Q1 EVM Circuit Diagram: RS232
Figure 8. Evaluation Board PGA450-Q1 EVM Circuit Diagram: USB Controller
Figure 9. Evaluation Board PGA450-Q1 EVM Circuit Diagram: PGA450-Q1
Figure 10. Evaluation Board PGA450-Q1 EVM PCB Layout: Top Layer
Figure 11. Evaluation Board PGA450-Q1 EVM PCB Layout: Bottom Layer
For details, see:
http://www.ti.com/lit/ds/symlink/pga450-q1.pdf
and
http://www.ti.com/lit/ug/sldu007/sldu007.pdf
The Links: FS450R12KE3 VI-2T0-EW