Any low power low frequency quadrature receivers?

Si4840-44.aspx

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I wonder if it can be operated at an arbitrary receive frequency, or if it's bound to the AM and FM bands.

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Why not roll your own with MC1596-style (Gilbert) multipliers?

Or use an amplifier with Gilbert-style AGC, like the MC1590? ...Jim Thompson

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Tayloe mixers excell here. The Ham SDR guys have all sorts of nice very low power designs, and the signal processing can be analog all pass filters.

Google "Softrock" SDR.. While not a single chip, with modern SMD you could get it quite small.

Steve

quickly takes up a lot of space

-Lasse

Almost ... but: According to the datasheet its DSP is limited to a cast-in-concrete command set. It doesn't allow piping I and Q straight through but does AM detection. No independent sideband processing :-(

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Regards, Joerg

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Well, then, how about the AD8339?

How about this one?:

12V 50mA (74HC4052 based):

Direct Conversion HF Receiver with DDS VFO, OH2NLT and OH7SV:

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12V 11mA:

Very High Performance Image Rejecting Direct Conversion Receivers Or how can an 11 ma receiver out perform the world?s best ham transceivers?:

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144MHz All Mode Transceiver:

MC1496:

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More here:

Glenn

Board space -- that's what the whole discussion about NE612 mixers, and CMOS switches, etc., was about.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com

That's the good old classical way with a very "busy" schematic:

Almost the same.

Yikes! Somebody must have been vey patient at the soldering station :-)

You get one lone mixer in a fairly big package, like with the SA612. After it's all said and done you've got a whole big circuit board full of stuff. I just won't have that much space in this case.

Thanks, Glenn. Unfortunately none of the authors seems to have found a more integrated solution than the usual concoction of single-part mixers and logic chips. If I absolutely have to I'll probably use logic chips, the main reason being that those can now be bought in TSSOP packages whereas mixers can't be.

--
Regards, Joerg

http://www.analogconsultants.com/

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Why not use a cheap microcontroller, low current like the Cortex M0 NXP series.

Simple analog bandpass filter of the incoming signal, syncronize a ADC from a PWM Local Osc generated by the micro, use a low frequency FIR filter to regenerate the shifted down signal from the undersampled output of the ADC.

The ADC needs to be triggered with low jitter, but that should be simple.

The Cortex M0 can run at full speed below 1mA, add another 1mA for a

1MSa/s ADC. A number of other microcontrollers can do the same, the Cortex is just a very nice part.

Regards

Klaus

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Size wise, the Cortex actually comes in a die version, 2 by 2 mm, Chip Scal= e Package (CSP)......

Regards

Klaus

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And you may need an external S/H if the ADC input frequency is to low....

If you feel you need to do direct conversion or analog I/Q (Ahem, I hope not!) Heyward's "Solid State Design for the Radio Amateur" is loaded with QRP direct conversion and many simple quadrature IF schemes.

I hope you find a AM/ssb chip.

Steve

You can also look at the Phillips App note for the "Weaver" method.

Steve

Steve

If you come up with anything cheap, please let me know. I'm looking for a SIMPLE SSB 144 Mhz IF for my 10.368 Ghz ham radio stuff. Preferably one that does not need hand picked microprocessor crystals for IF filters.

Steve

First we'd have to mix it down for that because my signal will be at

5-10MHz carrier frequency. Can also be undersampled, of course, but that'll cost a little SNR. Which would probably be ok in this application, we don't need to be able to hear the grass grow.

Initially I thought about using a PSoC because it already has digital blocks for the quadrature oscillator generation. Also switched-capacitor blocks which I should be able to "mis-use" as mixers, and then opamps for some gain. But I am not a programmer whizkid. Once we get into a higher volume project I'll revisit that, possibly a PSoC-3 is the ticket here if I disable the uC in there. The on-board ADC capabilities are a bit paltry though.

--
Regards, Joerg

http://www.analogconsultants.com/

Unfortunately, yes, that's exactly what I need to do.

My hope in that respect has dwindled quite a bit. There used to be a TDA-something chip but NXP has discontinued a lot of chips. Anything else I've seen falls more under the energy guzzler class where you pretty much can't operate it unless there is a wall outlet, and in this case there isn't.

--
Regards, Joerg

http://www.analogconsultants.com/

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AFAIC the psoc1 max mixer freq is in tens of kHz whereas the psoc3 can handle up to 1 MHz. You may be able to use the psoc1 internal analog bus as a integrated S/H, but I don't think the specs are to your liking.

Regards

Klaus