Hey all,
i'm making a supply for a high frequent scalair networkanalyzer. This beast gives signals from 10 to 18 GHz and needs a stable supply. I already made a print but have some problems with the pcb. Can anybody help me and say me what to change in the pcb because i know there is a little fault with the two opamps, they may not be connected to each other, but i dont know how to change it will work.
the working of the print:
the bias-spool and oscillator go immediatly to the powersupply, for the tuning-coil there is a whole regulatecircuit. The darlingtontransisotr gets a tension between 2.2 and 5V. To reach this i use a tensionregulator and two DA-convertors with a 'big' regulator of 2.3V (i do this by setting the inputtension over the tensiondevider and a buffer). The last contribution i get from a fine regulator thats create 0.5V.
With this all i can reach a maximal frequention for the YIG.
Dimensions of :
-Coarse regulator: R14: 4K7, R15: 3K9, R16: 100R
-Fine regulator: R11: 9K1, R12: 1K, R13: 11R
-fast tension: R1: 100R, R2: 6R8, R6: 270R (=4,4V, later deling/2)
-supply Op-Amps: R4: 10K, R5: 68K