TIDUFB9 April   2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Reference Design Features
      2. 2.2.2 Switch Settings
    3. 2.3 Highlighted Products
      1. 2.3.1 IWRL6432W
      2. 2.3.2 Crystal
      3. 2.3.3 TPS6285020M – 1.8V DC/DC Regulator
      4. 2.3.4 QSPI Flash Memory
  9. 3System Design Theory
    1. 3.1 Antenna
      1. 3.1.1 Range and Phase Compensation
      2. 3.1.2 Chirp Configuration
    2. 3.2 PCB
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 Reference Design
      2. 4.1.2 Small Form-Factor Reference Design
    2. 4.2 Software Requirements
    3. 4.3 Test Setup
    4. 4.4 Test Results
      1. 4.4.1 Human Detection at 15 Meters in Boresight
      2. 4.4.2 Antenna Radiation Plots
      3. 4.4.3 Angle Estimation Accuracy
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Authors

4.1.2 Small Form-Factor Reference Design

The small form-factor reference design has a 14-pin connector.

Table 4-1 Small Form-Factor Reference Design Pin Description
PIN NUMBER PIN NAME FUNCTIONALITY
1 (J3A) VCC_5V 5V power supply
2 (J3B) VCC_5V 5V power supply
3 (J3A) RS232_TX_1V8 UART B (RS232) TX
4 (J3B) SPI_MISO_REG_MODE_1V8 SPI MISO signal
5 (J3A) SPI_CS_I2C_SDA_1V8 SPI chip select, SDA of I2C
6 (J3B) GPIO2_1V8 GPIO
7 (J3A) SPI_CLK_I2C_SCL_1V8 SPI clock, SCL of I2C
8 (J3B) TDO_SOP0_1V8 SOP0 control
9 (J3A) RS232_RX_1V8 UART B (RS232) RX
10 (J3B) SPI_MOSI_1V8 SPI MOSO signal
11 (J3A) HOST_INTR_GPIO_1V8 GPIO
12 (J3B) RADAR_NRST_1V8 NRESET control pin
13 (J3A) GND Ground
14 (J3B) GND Ground

TIDEP-01040 Pin Description

Figure 4-1 Pin Description

The small form-factor reference design takes in 5V power. However, the IO voltage level is 1.8V, because the device operates in a single 1.8V supply. Match the IO voltage on the host side, .

The small form-factor reference design can be connected to host the PC using a LaunchPad™ Development Kit.


TIDEP-01040 Connection to Host PC Options

Figure 4-2 Connection to Host PC Options

TIDEP-01040 LaunchPad Development Kit Connection

Figure 4-3 LaunchPad™ Development Kit Connection

The LP-XDS110ET LaunchPad development kit can be used to connect the small form-factor reference design to the host PC. Consider the following points for this connection:

  1. The reference design can be powered directly by feeding the design with the 5V supply from the LaunchPad development kit.
  2. The reference design has 1.8V IO. However, the LaunchPad development kit has a default of 3.3V IO (P9 jumper position 1-2). To modify the LaunchPad development kit IO, position the P9 jumper to 2-3 (see Figure 4-3) to have the IO voltage from the target board.
  3. Connect 1.8V (reference design IO voltage) to pin 5 (LP_VDD) of P10 in the LaunchPad development kit to modify the LaunchPad development kit IO voltage to 1.8V.

The small form factor reference design uses 1.27mm pitch pins to reduce the form factor. However, 2.54mm pitch jumpers are needed to connect to most USB-to-UART adapters. Because of this, a pitch converter DR127D254P20F was used to connect with the USB bridges.

Figure 4-4 depicts this connection:


TIDEP-01040 Use of Pitch Converter

Figure 4-4 Use of Pitch Converter

In this procedure, the reference design is mated to the pitch converter. The 2.54mm pitch male headers from the other side of the pitch converter were used to make the connection. The following list includes a few cautionary items to consider while establishing the connection.

In this connection, jumper wires:

  1. Need to support the maximum peak current requirement for the power pins (5V), for example 200mA to 300mA
  2. Are of smaller and equal length without introducing large DCR to compromise data transfer speeds to lose information
  3. Need to have a small IR drop and inductance to prevent ringing on supply and GND