SLVUCG5 January   2023 TPS7H1111-SP

PRODUCTION DATA  

  1.   TPS7H1111EVM-CVAL
  2.   Trademarks
  3. 1Introduction
    1. 1.1 Related Information
    2. 1.2 Features
    3. 1.3 Applications
  4. 2Setup
    1. 2.1 Input/Output Connectors and Jumper Descriptions
      1. 2.1.1 Jumpers
      2. 2.1.2 Test Points
    2. 2.2 Equipment Setup
  5. 3Operation
  6. 4Adjustable Operation
  7. 5Test Results
    1. 5.1 Enable and Soft Start Timing
    2. 5.2 PSRR
    3. 5.3 Stability
    4. 5.4 Noise Spectral Density
  8. 6Board Layout
  9. 7Schematic
  10. 8Bill of Materials

5.2 PSRR

Figure 5-2 shows the typical PSRR performance of the TPS7H1111EVM-CVAL at various IOUT loads under the following conditions: VIN = 2.5 V, VBIAS = 5 V, VOUT = 1.8 V, CIN removed.

Figure 5-2 TPS7H1111EVM-CVAL PSRR vs IOUT

Measuring ultra high PSRR on a device can be challenging. To obtain adequate results, the output of the LDO is fed to a wideband amplifier with approximately 50 dB of gain. Amplifying the output effectively lowers the noise floor of the measuring instrument. Once results are obtained, the gain curve of the amplifier in dBs is added to the results across the frequency span.

The injected signal on VIN was -10 dBm into a 50 Ω load. This results in a 200 mV pk-pk signal. Additionally a small variable amount of injected signal attenuation was used starting at 100 kHz to minimize signal distortion at higher frequencies. Final injected signal power used was -17 dBm at approximatly 2 MHz.