Question
I would like to use HMC624ALP4E at 1MHz to 100MHz
Have few questions:
1. What would be the S21,S11,S22 at this range while ATT=0dB
2. What would be the IIP3?
3. What would be the P0.1dB?
4. What would be the IIP2?
Answer
HMC624A features ACGs pins so it can provide good small signal performances(insertion loss, return losses, attenuation accuracy) down to 1 MHz when thevalue of ACG and DC blocking capacitors is selected properly not to limit lowfrequency operation.
I have not evaluated the HMC624A down to 1 MHz but I had evaluated HMC472A,which is a very similar part to HMC624A, at low frequency range with differentACG cap values. Based on my test results posted in EZ(https://ez.analog.com/message/272340) , I would recommend to use ACG and DCblocking capacitors larger than 100nF for operating HMC624A at 1-100 MHz range.
HMC624A’s large signal performances (P0.1dB and IP3) degrade below 200 MHz ofwhich is a normal characteristic of GaAs digital attenuators. 50 MHz is theminimum frequency that we evaluated P0.1dB and IP3 of HMC624A. See below tablefor the test data of a single HMC624A part measured at insertion loss state,T=25C, Vdd=5V. Again by looking at the HMC472A test data in same EZ message,HMC624A is expected to have input P0.1dB of ~10dBm at 1 MHz.
We have not evaluated IP2 performance of HMC624A as IP2 is not a standard testparameter for our digital attenuators.
Frequency (MHz)Input P0.1dB (dBm)Input IP3 (dBm)5025.1749.0410029.4352.5215030.454.4720031.5554.9225032.1456.5330032.1556.0235032.0757.5640032.3455.6945032.3355.450032.858.08