5Mhz signal to dc converter circuit needed

Are you basically looking for a frequency to voltage converter??

LM2917 or LM2907 depending on the application, I don't know what its maximum frequency capability is, but you can check out the specs at National Semiconductor.

Hope that helps.

-- Myron Samila Toronto, ON Canada Samila Racing http://204.101.251.229/myronx19

Here is my favorite:

cut what follows into a text file called Detector.asc and open it using LTSpice: You can then play around with optimising the turn on time (determined primarily by the ratio of C2/C1), the turn off time (determined primarily by the C1R2 time constant) and the amount of ripple while it is on. My solution uses a series dc blocking capacitor so that you dont have to know which state (high or low) your RF source is in when no 5Mhz is present.

MikeM

___________________________________________________________________________

Version 4 SHEET 1 880 680 WIRE 192 304 192 240 WIRE 192 176 192 80 WIRE 192 80 144 80 WIRE 80 80 -32 80 WIRE -32 80 -32 176 WIRE -32 240 -32 304 WIRE -32 304 192 304 WIRE -32 368 -32 304 WIRE -512 112 -480 112 WIRE -512 112 -512 192 WIRE -512 352 -512 272 WIRE -160 80 -192 80 WIRE -96 80 -32 80 WIRE -480 112 -352 112 WIRE -192 80 -208 80 WIRE 304 160 304 80 WIRE 304 80 192 80 WIRE 304 240 304 304 WIRE 304 304 192 304 FLAG -32 368 0 FLAG -512 352 0 FLAG -480 112 i FLAG -192 80 o FLAG -32 80 c FLAG 192 80 d SYMBOL cap 176 176 R0 SYMATTR InstName C1 SYMATTR Value 1000p SYMBOL SpecialFunctions\\modulate -352 48 R0 WINDOW 3 0 0 Invisible 0 SYMATTR InstName A1 SYMATTR Value mark=5meg space=5meg SYMBOL voltage -512 176 R0 WINDOW 3 29 154 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value PULSE(0 2.5 0.5m 1u 1u 1m 2m) SYMBOL cap -96 64 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C2 SYMATTR Value 100p SYMBOL diode -16 240 R180 WINDOW 0 24 72 Left 0 WINDOW 3 24 0 Left 0 SYMATTR InstName D1 SYMATTR Value 1N4148 SYMBOL res 288 144 R0 SYMATTR InstName R2 SYMATTR Value 10k SYMBOL diode 80 96 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName D2 SYMATTR Value 1N4148 TEXT -176 384 Left 0 !.tran 3m TEXT -352 176 Left 0 ;5Mhz 5Vp-p

it sounds to me all you need is an RF switch. a nice little germanium diode as the detector into a small cap, this signal can drive a common emitter amp as the inverter that drives another inverter , the output of this can drive a current Boost stage(Unity gain).. that is just off the top of my head , there are more details that has to be worked out like the resistors etc.. if you don't get any where with this let me know i can most likely pop up a schematic of something that will work ok.

SUMNERE wrote:

Does it matter what the rise and fall time for the detector is?

Does it matter what the output impedence is?

If not you can do it with ine diode one capacitor and a resistor.

with

When

Scratch that. I read it again and see you want variable output voltage.

volts.

Like I said over in sci.electronics.design, the guy isn't clear what he wants. Take a bunch of people, and they will interpret his vague post multiple ways.

Michael