PLL ICs with analog multiplier phase detectors ? Are they still around ?...

[Ricky]

On Tuesday, May 30, 2023 at 12:42:45 AM UTC-4, boB wrote:

On Sun, 28 May 2023 08:56:25 -0700 (PDT), whit3rd <whi...@gmail.com
wrote:
On Saturday, May 27, 2023 at 5:48:44?PM UTC-4, boB wrote:
Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ? Parts that are active
and still being manufactured ?

The analog multiplier function in figure 24 here

https://www.ti.com/lit/ds/symlink/lm13700.pdf

only requires half a LM13700, and some resistors.
Thanks. That part number did cross my mind.

I think that a cheap ARM like JL mentioned is the way to go here.

Why screw with an MCU when you can do this easily in an FPGA? Even a small FPGA is more than adequate to implement all the functions for this. Efinix parts are very inexpensive and they now have a 100 pin QFP so you don\'t need to screw around with BGAs.

You don\'t say what resolution you need in the ADC, but you can use differential inputs to create a sigma-delta like converter that will give you 12 bits without trouble. So, no external ADC.

One big advantage of FPGAs is no need for trying to make a single processor look like multiple processors, with all the attendant issues you have to deal with.

--

Rick C.

-- Get 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209

 

[Phil Hobbs]

John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote:

On Tue, 30 May 2023 10:32:41 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2023-05-30 00:32, boB wrote:
On Mon, 29 May 2023 17:17:40 -0000 (UTC), Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Joe Gwinn <joegwinn@comcast.net> wrote:
On Mon, 29 May 2023 16:01:30 -0000 (UTC), Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Joe Gwinn <joegwinn@comcast.net> wrote:
On Mon, 29 May 2023 01:34:50 -0000 (UTC), Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
Joe Gwinn <joegwinn@comcast.net> wrote:
On Sun, 28 May 2023 18:04:55 -0000 (UTC), Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Joe Gwinn <joegwinn@comcast.net> wrote:
On Sat, 27 May 2023 21:52:07 -0700, boB <boB@K7IQ.com> wrote:

On Sat, 27 May 2023 21:10:34 -0700, John Larkin
jlarkin@highlandSNIPMEtechnology.com> wrote:

On Sat, 27 May 2023 21:01:32 -0400, bitrex <user@example.net> wrote:

On 5/27/2023 7:36 PM, John Larkin wrote:
On Sat, 27 May 2023 14:48:28 -0700, boB <boB@K7IQ.com> wrote:



Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ? Parts that are active
and still being manufactured ?

I used to use ones like the XR-215 and some others but have not seen
any for many years now.

The 74HC4046 is OK but not the phase detector I am looking for.

Not for microwave use. Much lower frequency than those kinds.

boB

You could make one. Use a dual comparator and an xor gate for the
multiplier.

Or a quad XOR gate to be really cheap.



Using the SLG46537 mixed-signal PLC or similar you can build a pair of
nice edge detectors with its four onboard comparators maybe sort of like
this:

https://patents.google.com/patent/EP0643484A1/en

And then with the 8 stage async state machine you can implement several
phase detector topologies, once you\'ve got edges for firing the
transitions.

I think 25 cents or so in small quantity:

https://www.renesas.com/us/en/products/programmable-mixed-signal-asic-ip-products/greenpak-programmable-mixed-signal-products/greenpak-asynchronous-state-machine/slg46537-greenpak-programmable-mixed-signal-matrix-asynchronous-state-machine

Yes, you can make a nice phase-frequency detector in an FPGA.


Thanks for the suggestions.

We do already use the Silego Greenpak devices. Great parts !

This question was intended to find one like the old PLL chips that,
Like Phil Hobbs said, are all gone now. As fo the MC1496, we used to
actually use those many decades ago in an FM tuner we used to make.

The reason for the analog multiplier instead of digital comparator or
zero crossing detector is that this was going to be used for synching
to 60Hz (ish) AC grid or generator sine-waves that may very well be
distorted. Especially genny waveforms. Those do not ensure that zero
crossing is clean and detectble repeatably.

I had even looked to try and find an analog multiplier IC and those
are not availabe for cheap. Could make one out of log amps using
CD3046 transistor arrays but that is quite a few parts.

I think that the way to do this may actually be to use a cheap ARM
Cortex M0+ or similar micro with at least 2 A/D inputs and at least
some speed. 60 Hz area should work easily done with a 48 MHz
part I think. The whole PLL should be able to be done in one of these
actually. Digital filtering and all.

You are basically trying to estimate the phase and frequency of the
fundamental of a distorted signal, where the fundamental is known to
be very close to 60 Hz. This is easily done by fitting a sinewave
function to the A/D samples in a batch maybe a second or two long, so
long as the distortion isn\'t too bad. If it is bad, some added
complication is needed, such as modeling a few of the harmonics as
well.

Joe Gwinn


The multiply-and-average approach is guaranteed to work, though, and
fitting isn?t.

Because fitting emphasizes the worst outliers, it falls apart completely at
low SNR, whereas multiply+average works even with SNRs way below 0 dB.

True in general, but with a power source, wideband random noise isn\'t
usually the problem, it\'s waveform distortion due to the generator
design, plus power-system transients.

Which is why in practice one does some data grooming first, like
impulse clamping or blanking, if the impulses are common enough to
matter.

I would assume that a distorted waveform may also affect the imputed
zero crossing locations from multiply-and-average, at least the odd
harmonics will, but I don\'t know how important that is for the OP\'s
intended use. Probably will want to clamp the transients as well.

Joe Gwinn


Nope. Multiply and average pulls out the in-phase fundamental component to
any accuracy you like (and that your digitizer can manage), while ignoring
all the harmonics to the same accuracy.

There are the usual Shannonish tradeoffs between accurate tracking of FM
and noise elimination, but you can notch out the harmonics by simply
averaging for an integer number of cycles.

Having the correct phase vs time, the same numerical oscillator code will
make a clean replica shifted by 90 degrees so as to match the fundamental
component of the input.


I should say that if one is trying to lock to an edge, rather than to the
fundamental component, life does get harder and less well defined as the
SNR drops or the waveform gets gnarlier-looking, as you say.

Yes. And doesn\'t the multiply-and-average approach implicitly depend
on the full-bandwidth waveform being symmetric in time? Said another
way, would the zero-crossings of a asymmetric triangle wave be
precisely located in time?

The theorems are correct, so the phase of the fundamental can be located to
any accuracy you like, regardless of the waveform symmetry or lack of it.

Which theorems?

Fourier decomposition. You derive each Fourier coefficient as the
normalized overlap integral of the corresponding eigenfunction and the
given function. The computation becomes exact as the limits of integration
go to infinity.




This application is for an inverter synchronizing to grid.

We are doing this now in software both ways. Zero crossing detect and
multiplier/filtering PLL. The zero-cross method works but can be a but
jumpy once in a while. The more complicated method works better I
think but takes a lot of processor time. It CAN also become somewhat
unstable if not given the right coefficient values etc.

If you tweak it wrong, it\'ll lose lock, for sure. The loop can also
oscillate while remaining in lock (more or less).

A reliable way of doing the lock detection is to do the multiplication
with both the sine and cosine components of the reference. The loop
will lock at quadrature, where the other multiplication reaches a peak.

Multiply-and-average is much better than a phase-frequency detector.
PFDs are sensitive to the number of edges, so any time you get a
spurious edge, the loop loses lock and has to reacquire. Multiplying
phase detectors and even XOR gates are much better if the signals aren\'t
squeaky-clean. An XOR doesn\'t care about transitions, just the duty
cycle of the result.

To save processor time, you could use a simple IIR filter to knock down
the harmonics a bit, and then multiply by +-1, giving the rough
equivalent of an OR phase detector with lock detection. If you pick the
coefficients cleverly, you can do it all with a few shifts and adds.

(You want to avoid thresholding the filtered signal before
XORing--otherwise junk happening near the zero crossing will get
amplified a lot.)


Since it can be computationally intensive so I was trying to see if
there might be an out of the main microcontroller\'s code space method
of accomplishing this part, inexpensiviely. Another micro, although a
cheap micro can do this instead of an old style PLL IC.

(The RF PLL chips weren\'t that great either.)

Cheers

Phil Hobbs

It wouldn\'t take much of a uP to make a software quadrature DDS and do
a multiply against the digitized line waveform and use the product to
servo the DDS phase or frequency.

Agreed, if it’s a new design. Even a Cortex M0+ has a single-cycle 32x32
multiplier.

Do that calc at some modest number
of KHz. It averages, so ignores noise and harmonics that would wobble
a zero-cross detector.

Yup. Extra credit for picking a sampling frequency that won’t alias nearby
harmonics down inside the loop bandwidth.

One could do a true phase - not frequency - locked loop too.

Yes, it’s PLLs that are in view—a frequency-locked loop wouldn’t do it.

Another idea: make a software bandpass filter but turn it into an
oscillator when the line voltage fails. Just for fun; the DDS makes
more sense.

Or use a uP internal timer (most have them) and sync it with the line
frequency, and free-run when the line fails. That could be really
easy.


Cheers

Phil Hobbs


--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics

 

[Simon S Aysdie]

On Saturday, May 27, 2023 at 5:02:36 PM UTC-7, Phil Hobbs wrote:

boB <b...@K7IQ.com> wrote:


Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ? Parts that are active
and still being manufactured ?

I used to use ones like the XR-215 and some others but have not seen
any for many years now.

The 74HC4046 is OK but not the phase detector I am looking for.

Not for microwave use. Much lower frequency than those kinds.

boB

All the analog AM/FM radio chips are gone. You can still get the MC1496,
which is sort of a DIY version.

I guess Renasas picked up the Harris/Intersil business. Haven\'t searched for years, but this old part popped up:
https://www.renesas.com/us/en/products/analog-products/amplifiers/transistor-arrays/hfa3101-gilbert-cell-uhf-transistor-array

 

[Phil Hobbs]

Simon S Aysdie <gwhite@ti.com> wrote:

On Saturday, May 27, 2023 at 5:02:36 PM UTC-7, Phil Hobbs wrote:
boB <b...@K7IQ.com> wrote:


Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ? Parts that are active
and still being manufactured ?

I used to use ones like the XR-215 and some others but have not seen
any for many years now.

The 74HC4046 is OK but not the phase detector I am looking for.

Not for microwave use. Much lower frequency than those kinds.

boB

All the analog AM/FM radio chips are gone. You can still get the MC1496,
which is sort of a DIY version.



I guess Renasas picked up the Harris/Intersil business. Haven\'t searched
for years, but this old part popped up:
https://www.renesas.com/us/en/products/analog-products/amplifiers/transistor-arrays/hfa3101-gilbert-cell-uhf-transistor-array

I’ve long wanted to find a good use for the HFA-series parts, but so far
they’ve never been the right medicine. The usual issue is their high Ree’
and Rbb’, respectively around 10 and 100 ohms iirc.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics

 

[Gerhard Hoffmann]

Am 03.06.23 um 00:04 schrieb Phil Hobbs:

Simon S Aysdie <gwhite@ti.com> wrote:

I guess Renasas picked up the Harris/Intersil business. Haven\'t searched
for years, but this old part popped up:
https://www.renesas.com/us/en/products/analog-products/amplifiers/transistor-arrays/hfa3101-gilbert-cell-uhf-transistor-array


I’ve long wanted to find a good use for the HFA-series parts, but so far
they’ve never been the right medicine. The usual issue is their high Ree’
and Rbb’, respectively around 10 and 100 ohms iirc.

They have transistor arrays with 5.5 GHz PNPs, a nwarly
died-out species.

<
https://www.renesas.com/us/en/document/dst/hfa3046-hfa3096-hfa3127-hfa3128-datasheet
>

I even got them in space-proof flat packs some years ago.

Cheers

Gerhard

 

[Phil Hobbs]

Gerhard Hoffmann <dk4xp@arcor.de> wrote:

Am 03.06.23 um 00:04 schrieb Phil Hobbs:
Simon S Aysdie <gwhite@ti.com> wrote:

I guess Renasas picked up the Harris/Intersil business. Haven\'t searched
for years, but this old part popped up:
https://www.renesas.com/us/en/products/analog-products/amplifiers/transistor-arrays/hfa3101-gilbert-cell-uhf-transistor-array


I’ve long wanted to find a good use for the HFA-series parts, but so far
they’ve never been the right medicine. The usual issue is their high Ree’
and Rbb’, respectively around 10 and 100 ohms iirc.

They have transistor arrays with 5.5 GHz PNPs, a nwarly
died-out species.

Too true. I just wish they were as good as an NE97733 or even a BFT92.

The NTE2403 maintains a shadowy existence.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics

 

[shiv Singh]

On Saturday, 3 June 2023 at 01:51:37 UTC+5:30, Simon S Aysdie wrote:

On Saturday, May 27, 2023 at 5:02:36 PM UTC-7, Phil Hobbs wrote:
boB <b...@K7IQ.com> wrote:


Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ? Parts that are active
and still being manufactured ?

I used to use ones like the XR-215 and some others but have not seen
any for many years now.

The 74HC4046 is OK but not the phase detector I am looking for.

Not for microwave use. Much lower frequency than those kinds.

boB

All the analog AM/FM radio chips are gone. You can still get the MC1496,
which is sort of a DIY version.


https://mp3ringtonedownload.net

https://mp3ringtonedownload.net/bgm
https://mp3ringtonedownload.net/top
https://mp3ringtonedownload.net/hot

I guess Renasas picked up the Harris/Intersil business. Haven\'t searched for years, but this old part popped up:
https://www.renesas.com/us/en/products/analog-products/amplifiers/transistor-arrays/hfa3101-gilbert-cell-uhf-transistor-array

https://mp3ringtonedownload.net

 

[RichD]

On May 27, Phil Hobbs wrote:

Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ?
The 74HC4046 is OK but not the phase detector I am looking for.

All the analog AM/FM radio chips are gone.

The laws of physics have gone digital?

--
Rich

 

[Phil Hobbs]

RichD <r_delaney2001@yahoo.com> wrote:

On May 27, Phil Hobbs wrote:
Is anybody making a PLL IC with multiplier input phase detector that
doesn\'t cost, like $50+ from Analog Devices ?
The 74HC4046 is OK but not the phase detector I am looking for.

All the analog AM/FM radio chips are gone.

The laws of physics have gone digital?

You just had to do that, didn’t you? Set us up for another of our
interminable threads on how charge conservation shows that even classical
electrodynamics is discrete, and so all analog circuits are really digital.


To the usual suspects: Don’t. Just don’t.


--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics

 

[RichD]

On June 5, Phil Hobbs wrote:
> and so all analog circuits are really digital.

I\'d argue the opposite -

> To the usual suspects: Don’t. Just don’t.

I believe the actual admonition was to round them up -

--
Rich