SLAU891A March   2023  – July 2024 TRF0208-SEP

 

  1.   1
  2.   Description
  3.   Features
  4.   4
  5. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
  6. 2Hardware
    1. 2.1 General Usage Information
  7. 3Implementation Results
    1. 3.1 Test Setup Diagrams
      1. 3.1.1 S-Parameter Test Setup
      2. 3.1.2 Noise Figure Test Setup
      3. 3.1.3 Two-Tone OIP3 Test Setup
  8. 4Hardware Design Files
    1. 4.1 Schematic
    2. 4.2 PCB Layers
      1. 4.2.1 Stack-Up and Material
    3. 4.3 TRF0208SEP/SP EVM Bill of Materials
  9. 5Additional Information
    1.     Trademarks
  10. 6Related Documentation
  11. 7Revision History

2.1 General Usage Information

This section provides general usage information for the TRF0208SEP/SP EVM. Figure 2-1 shows a general single tone setup diagram, which is a reference point for the following instructions (some components, such as supply bypass capacitors, are omitted for clarity):

  1. Recommended power up sequence:
    1. Before connecting the power-supply cables to the EVM, set the DC output power supply to +3.3V.
    2. Set the current limit of the DC output power supply at 250mA.
    3. Making sure the supply is turned off, connect the power supply cables to the J1 connector of the EVM.
    4. Now, turn on the DC power supply of VCC = +3.3V. The supply current (IQ) drawn from the power supply needs to be approximately 135mA.
    5. If the supply current is low, then make sure that the device is not disabled by the PD pin.
  2. Power-down option:
    1. Connect +1.8V (logic-1) on PD pin to power-down the chip. Ground the PD pin to enable the chip.
  3. Single tone measurement setup recommendation:
    1. Connect an RF signal generator to input SMA connector, J4.
      When measuring single tone distortion, use an RF band pass filter as shown in Figure 2-1.
    2. The RF signal generator used must support up to 12GHz signal frequency for testing out the TRF0208SEP/SP EVM.
    3. The TRF0208SEP/SP device input is 50Ω in the pass-band.
      To minimize signal reflections due to impedance mismatch, TI recommends using an attenuator pad of approximately 3dB to 6dB between the source and J4 SMA input.
    4. The EVM outputs are fully differential (or 180° out-of-phase) at J5 and J6 SMA connectors.
      The TRF0208SEP/SP device has low output impedance at dc and low frequencies.
    5. When connecting to a spectrum analyzer, the differential signal out of the EVM needs to be converted to a single-ended signal using an external passive balun as shown in Figure 2-1.
      Usage of an attenuator pad of approximately 3dB to 6dB is recommended at the three terminals of the passive balun to minimize reflections.
    6. Lastly, TI recommends to properly characterize and account for the insertion loss of RF coaxial (coax) cables, attenuator pads, and passive baluns to measure accurate gain and power levels for the device.
  4. Matching considerations:
    1. TRF0208SEP/SP is a wide-band amplifier and expects 50Ω input matching over the operating bandwidth up to about 12GHz. A signal generator or noise source that drives this EVM has 50Ω impedance over a wide band width. But, if this EVM is driven by a narrow-band driver or a source that has non 50Ω matching, then there can be instability issues with the amplifier. To avoid such issues, additional matching can be require at the input. For more information, see the TRF0208SEP 10MHz to 11GHz 3dB BW, ADC Driver Amplifier data sheet.
    2. As mentioned earlier, the TRF0208SEP/SP device has low output impedance, and zero-ohm series resistors are used in the EVM. When the EVM outputs are connected to a balun, TI recommends to use attenuator pads to minimize reflections.