SWRA640H December   2018  – May 2024 CC1310 , CC1312R , CC1314R10 , CC1350 , CC1352P , CC1352R , CC1354P10 , CC1354R10 , CC2620 , CC2630 , CC2640 , CC2640R2F , CC2640R2F-Q1 , CC2642R , CC2642R-Q1 , CC2650 , CC2652P , CC2652R , CC2652R7 , CC2652RB , CC2652RSIP , CC2674P10 , CC2674R10

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Reference Design
    1. 1.1 Sub-1GHz LaunchPads
      1. 1.1.1 LAUNCHXL-CC1310
      2. 1.1.2 LAUNCHXL-CC1312R
    2. 1.2 2.4GHz LaunchPads
      1. 1.2.1 LAUNCHXL-CC2640R2
      2. 1.2.2 LAUNCHXL-CC26x2R
      3. 1.2.3 LP-CC26x1
    3. 1.3 Dual-Band LaunchPads
      1. 1.3.1 LAUNCHXL-CC1350EU/US
      2. 1.3.2 LAUNCHXL-CC1350-4
      3. 1.3.3 LAUNCHXL-CC1352R
      4. 1.3.4 LAUNCHXL-CC1352P1
      5. 1.3.5 LAUNCHXL-CC1352P-2
      6. 1.3.6 LAUNCHXL-CC1352P-4
      7. 1.3.7 LP-CC1352P7-1
      8. 1.3.8 LP-CC1352P7-4
      9. 1.3.9 LP-EM-CC1354P10-6
    4. 1.4 Reference Design Overview
  5. 2 Front-End Configurations
    1. 2.1 Overview of Front-end Configurations
    2. 2.2 Configuring the Front-End Mode
    3. 2.3 CC13xx Single-Ended Mode
      1. 2.3.1 Single-Ended Modes
      2. 2.3.2 Single-Ended TX-Only
      3. 2.3.3 Single-Ended RX-Only
      4. 2.3.4 Single-Ended Modes - 2.4GHz
    4. 2.4 CC26xx Single-End Mode
  6. 3 Schematic
    1. 3.1 Schematic Overview
      1. 3.1.1 24/48MHz Crystal
      2. 3.1.2 32.768kHz Crystal
      3. 3.1.3 Balun
      4. 3.1.4 Filter
      5. 3.1.5 RX_TX Pin
      6. 3.1.6 Decoupling Capacitors
      7. 3.1.7 Antenna Components
      8. 3.1.8 RF Shield
      9. 3.1.9 I/O Pins Drive Strength
    2. 3.2 Bootloader Pins
    3. 3.3 AUX Pins
      1. 3.3.1 Reference
      2. 3.3.2 CC26x2/CC13x2 AUX Pins
      3. 3.3.3 CC26x0/CC13x0 AUX Pins
    4. 3.4 JTAG Pins
  7. 4 PCB Layout
    1. 4.1  Board Stack-Up
    2. 4.2  Balun - Sub-1GHz
    3. 4.3  Balun - 2.4GHz
      1. 4.3.1 Recommended Layout and Considerations for 20dBm
    4. 4.4  LC Filter
    5. 4.5  Decoupling Capacitors
    6. 4.6  Placement of Crystal Load Capacitors
    7. 4.7  Current Return Path
    8. 4.8  DC/DC Regulator
    9. 4.9  Antenna Matching Components
    10. 4.10 Transmission Lines
    11. 4.11 Electromagnetic Simulation
  8. 5 Antenna
    1. 5.1 Single-Band Antenna
    2. 5.2 Dual-Band Antenna
      1. 5.2.1 Dual-Band Antenna Match Example: 863-928 MHz and 2.4 GHz
      2. 5.2.2 Dual-Band Antenna Match: 433-510MHz and 2.4GHz
  9. 6 Crystal Tuning
    1. 6.1 CC13xx/CC26xx Crystal Oscillators
    2. 6.2 Crystal Selection
    3. 6.3 Tuning the LF Crystal Oscillator
    4. 6.4 Tuning the HF Oscillator
  10. 7 TCXO Support
    1. 7.1 Hardware
    2. 7.2 Software
    3. 7.3 Example: Usage of TCXO on CC1312R Launchpad
  11. 8 Integrated Passive Component (IPC)
  12. 9 Optimum Load Impedance
  13. 10PA Table
  14. 11Power Supply Configuration
    1. 11.1 Introduction
    2. 11.2 DC/DC Converter Mode
    3. 11.3 Global LDO Mode
    4. 11.4 External Regulator Mode
  15. 12Board Bring-Up
    1. 12.1 Power On
    2. 12.2 RF Test: SmartRF Studio
    3. 12.3 RF Test: Conducted Measurements
      1. 12.3.1 Sensitivity
      2. 12.3.2 Output Power
    4. 12.4 Software Bring-Up
    5. 12.5 Hardware Troubleshooting
      1. 12.5.1 No Link: RF Settings
      2. 12.5.2 No Link: Frequency Offset
      3. 12.5.3 Poor Link: Antenna
      4. 12.5.4 Bluetooth Low Energy: Device Does Advertising But Cannot Connect
      5. 12.5.5 Poor Sensitivity: DCDC Layout
      6. 12.5.6 Poor Sensitivity: Background noise
      7. 12.5.7 High Sleep Power Consumption
  16. 13References
  17. 14Revision History

10 PA Table

The PA table for the various devices is provided in SmartRF Studio. The txpower values used in the table are selected to provide as low as possible device to device variation. In addition, the txpower setting has a built-in temperature compensation giving a very low output variation as a function of temperature.

The PA used is designed to be highly effective on maximum power. With maximum power the PA is in saturation and due to this the device to device variation is low. For lower power settings, the PA is in the linear region and the output power will therefore be dependent on the transistor gain, which will have a higher device to device variation. For the output powers not covered by the PA table provided by SmartRF Studio, it has not been possible to find a txpower setting that gives a low device to device variation or a stable output power over temperature.

It is possible for customers to generate a custom PA table if that is needed. The output power of a FEM will typically not be constant as a function of temperature and it could be possible to find a txpower value that gives a more constant output power over temperature when using a FEM.

The parameter txPower contains temp. coefficient setting, gain setting, IB setting and the TX BOOST bit:

  • txPower[15:9]: temp coefficient
  • txPower[8]: TX BOOST bit
  • txPower[7:6]: Gain
  • txPower[5:0]: IB

The temperature coefficient is applied to automatically compensate the IB setting based on the temperature readout of AON_BATMON_TEMP.

There are three different gain settings and for each gain setting the IB can be adjusted from 0x0 to 0x3F resulting in 64*3 192 available settings for TX output power. The temperature coefficient is given as an input in addition to the requested gain and IB setting.Based on the readout from the temperature sensor and the temperature coefficient setting the IB is adjusted. IB is adjusted based on Equation 3.

Equation 3. CC1354P10-6

A custom TX power table should be generated by the following method (to obtain constant Tx power over temperature for a certain Tx parameter value):

  1. Room temp setting: Adjust the gain and IB setting to get the requested output power level at room temperature with temperature compensation disabled. This setting will be the Ib_requested.
  2. Low temp setting: Use the same gain setting and adjust the IB setting to get the closest output power level from step 1 at low temperature. This setting will be the Ib_low_temp.
  3. High temp setting: Use the same gain setting and adjust the IB setting to get the closest output power level from step 1 at high temperature. This setting will be the Ib_high_temp.
  4. Calculate temp coefficient. Use the IB settings from the low and high temperature measurements to calculate the temperature coefficients. The temp coefficient is based on a linear approximation between the two temperature extremes and calculated as shown in Equation 4.
    Equation 4. CC1354P10-6
    Equation 5. I b   =   I b r e q u e s t e d + ( T e m p e r a t u r e   -   25   d e g ) · t e m c o e f f 256
    Equation 6. t e m p _ c o e f f   =   256 · ( I b _ h i g h _ t e m p - I b _ l o w _ t e m p ) h i g h _ t e m p - l o w _ t e m p
  5. Repeat step 1-3 for all the desired power levels.