SWRA577A October   2017  – November 2020 AWR1243 , AWR1443 , AWR1642 , AWR1843 , AWR1843AOP , AWR2243 , AWR6843 , IWR1443 , IWR1642 , IWR1843 , IWR6443 , IWR6843 , IWR6843AOP , LP87524B-Q1 , LP87524J-Q1

 

  1.   Trademarks
  2. 1Introduction
  3. 2Power Supply Ripple and Noise Specifications
  4. 3Reference Solution
  5. 4Low Cost LC Filter Solution
    1. 4.1 LDO vs LC Filter Scheme Comparison
      1. 4.1.1 Waveguide Loopback Tests
      2. 4.1.2 Spur/Noise Floor Level
      3. 4.1.3 Voltage Transient Behavior
    2. 4.2 System Tests
      1. 4.2.1 Sensor Configuration
      2. 4.2.2 System Test With Static Object
      3. 4.2.3 Spur/Noise Floor Level
  6. 5Summary

4.1.2 Spur/Noise Floor Level

The measurements shown in Table 4-3 are done with TX to RX loopback with Tx Back-0ff=0 and Complex Rx gain=33dB.

Table 4-3 Spur/Noise Level Measurements With Tx to Rx Waveguide Loopback
PM SchemeIdle Channel Noise Floor (Rx-alone) at the ADC Output (dBFs/Hz)Amplitude Level of PMIC Ripple Frequency Spur (4.05M-4.17M) Seen at the ADC Output (dBFs)(Tx+Rx) SNR
dBc/Hz		Amplitude Level of PMIC Ripple Frequency Spur (4.05M-4.17M) Seen at the ADC Output (dBFs)
Additive (Rx1 - alone)Loop back (Tx2-Rx1)
LDO Scheme-138.80Not seen-118.74Not seen (less than noise floor)
LC Filter Scheme-138.27Not seen-120.6-104