Hi-Fi audio preamplifier using Burr-Brown PGA2310

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

Stanga wrote:Hi Fotios, great job :D .
But any chance of also posting the code in FlowCode4? Not all of us have Flowcode 5 yet.
Thanks Stanga for your kind words. As i said, i used FCv5 just for its improved simulator, the error messages panel etc. I will have ready the FCv4 file tomorrow, as i have promised.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis

Nice to see your preamp up and running. I downloaded the fcf file of your preamp. Did you have a chance to take a look at the fcf file of my preamp?.

Thanks for your help :)

Have a good day

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis

Nice to see your preamp up and running. I downloaded the fcf file of your preamp. Did you have a chance to take a look at the fcf file of my preamp?.

Thanks for your help :)

Have a good day

Phil
Hi Phil, thanks for your kind words
I am currently in the process of translation FCv5 file in FCv4 as asked me member "Stanga". I hope i will finish it tonight. Regarding your fcf, forgive me for the delay, as i told you we had some health issues but now we are fine. Please - if you believe in God - make a prayer for me to be fine in my health (as we say in Greece) :) Everything else is easy!
Though i haven't did audition tests so far, in workbench tests the project shows amazing good performance. I knew it that LME49710 (as well LME49720) has amazing good performance, my big surprise was that PGA2310 shows the same! That is obvious in the DSO screen shot that i attached in my previous post.
Though i have big plans :D based on your idea - building a general audio signal "control and routing" station - i will try tomorrow to take a look on your fcf and to make some corrections. I also found a whole tray of 10 pieces OMRON G6A-234P-5V simple DPDT relays on e-Bay for just 5GBP! Next week, when i will have money left-over i will order them to proceed in the developement of this big project.
Hey Phil, you forgot to write me the brand and the type of your relays. Please inform me about.
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The PGA2310 preamplifier project in FC v4

Post by fotios »

As I promised, here is the file in FC v4. Is working and is tested on actual hardware.
You can run it in simulator. All functions can be simulated – except RC5 receiver of course – as PortB IOC interrupt is not anymore used.
I did an unusual configuration on P16F887 due to hardware issues. Power-Up timer and Brown – Out detect functions are disabled. Only the MCLR function is used and is allocated to the internal module of micro. Why this? Because of the nature of Latching relays and the functionality of PGA2310 during reset. If a Power failure occurs during normal operation, the Output Mute relay and the Power-On relay remain in On state. When power is again applied , these two relays must be instantly cleared. The PGA2310 internal registers are also cleared during power-up. From those I have seen with DSO in the output of preamp, before PGA2310 executes a self-clear of its internal registers, they get instantly their max value (+31dB) and then turned back to zero. If a signal is applied in the input at this time, a large peak will be presented in output for a while, until the MCLR function of MCU will be completed. So, reset must be as fast as possible. PWRT and BOR when enabled, add an extra reset time of 64ms. For this reason I disabled them. I don’t know if it is wrong, but in practice it shows that works well.
Instructions for remote control initialization
The micro is programmed to communicate with any RC5 compatible remote control handset. Each handset transmits a unique address code, e.g. TV address = 0 and Preamplifier address = 16. To initialize the micro communication with a handset, you have to turn off the power. Then turn on again the power to micro, and immediately (within 3 seconds) press the MUTE switch mounted on micro PCB. A message “INITIALISE REMOTE CONTROL” appears on LCD screen. Now you have to press firmly any switch on remote control until a message “ADDRESS = XX” appears on LCD. That finishes the initialization of micro. A confirmation message “REMOTE CONTROL READY !!!” appears on LCD, and immediately the device is placed in Stand By mode. That is all, there is no need of making the same process each time, the handset address is stored in EEPROM memory and its communication with micro has been established.

Thanks for your attention
Fotis
Attachments
PGA2310_PAN_5LATv4.fcf
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Last edited by fotios on Thu Feb 16, 2012 6:58 am, edited 1 time in total.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis,

Please don't worry if you haven't had the time to look at my fcf file, no hurry at all. Also I will keep my fingers crossed for your health :D

The relays I have spare to use for this project are OMRON - G5V-2-H-DC5 DPDT 5VDC SIGNAL Relays. I also have some very nice quality NEC - EA2-5NU DPCO 5VDC Relays. They have gold plated contacts :)

Thanks again for your help

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by Stanga »

Thanks for posting the FC4 file Fotios.

I have been studying it with the view to add an option that I first built into two commercial products in 2005/2006. They both have the option to edit the name on the LCD display of each of the devices connected to the audio inputs. Maybe we can all put our thinking caps on together and work out the most memory efficient way to go about it.

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis

I've tried the fcf file for your preamp, for some reason I can't use my remote to control the preamp. When I try to use the set up mode to initialise the remote it either shows on the display "Address - 65" or "Address 125". Could this be a problem with the remote I'm using. The remote I'm using does emit RC-5 commands.

Thanks Fotis

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis

I've tried the fcf file for your preamp, for some reason I can't use my remote to control the preamp. When I try to use the set up mode to initialise the remote it either shows on the display "Address - 65" or "Address 125". Could this be a problem with the remote I'm using. The remote I'm using does emit RC-5 commands.

Thanks Fotis

Phil
Hi Phil
I am sorry to hear this. The RC-5 address bits are just 5. If all 5 address bits are "1" (11111b = 1Fh = 31d) the maximum address number should be "31". The most usual remote control handsets offered on the market are those "universal remote controls for TV sets". Because RC-5 is one of the oldest protocols, almost all universal handsets include it. In my program code a whole register of 8 bits is used to store the address number, so "65d" = 41h = 0100 0001b. And "125d" = 7Dh = 0111 1101b. BTW i will do an upgrade in program code; when received Address is biger than "31d" the display will show "Incompatible Remote Control Handset".
Are you sure that your remote control is RC-5 compatible? Address like "65" or "125" are not compatible. Can you post me some data (brand, type) of your remote control? If it is for TVs then you should get a message "ADDRESS = 0" on display during set up.
Please let me know.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis

The Remote came with a remote control kit from a manufacturer called Analog Metric. They have a website (http://www.analogmetric.com) and if you type "ir remote" in the search bar it will show 3 different kits that can be purchased. The 3 are essentially the same with different options but the main PCB in both kits are exactly the same. The instruction manual does say that the remote uses RC-5 commands. I have also noticed that the address numbers change every time I go to initialize remote setup and not press any button on my remote handset, the display will usually show address 125, 65 or 61 when I go to the set up menu. I have tried using another IR receiver for the preamp just in case I have bought a faulty receiver but I end up with the same problem

I will try and find a different remote, I'm sure I have one of those "One For All" remotes some where in the house :) so I might try it and use the codes in the instructions for philips devices

How are you getting on with my fcf code? you having any luck with it?

Thanks again Fotis for your help

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis

I've tried the fcf file for your preamp, for some reason I can't use my remote to control the preamp. When I try to use the set up mode to initialise the remote it either shows on the display "Address - 65" or "Address 125". Could this be a problem with the remote I'm using. The remote I'm using does emit RC-5 commands.

Thanks Fotis

Phil
Hi again Phil
Please, change the old fcf with the attached new. I did - in fast - some upgrades:
1) If you put the preamp in address set up mode (by pressing the on board MUTE switch) without pressing any button on remote control, then you will get a message "NO SIGNAL!" on display. Then the program automatically sets the address = "0", that is the TV code in RC-5.
2) If the address that transmits your remote control is higher than "31", then display shows "INCOMPATIBLE ADDRESS CODE". Then, the program sets the address again to "0".
Hope this will help you.
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PGA2310_PAN_5LATv4.fcf
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis,

Thank you for modifying the code :)

Would you be happy to post the hex file of the new code?.

Thanks

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis,

Thank you for modifying the code :)

Would you be happy to post the hex file of the new code?.

Thanks

Phil
Hi Phil
If you have not noticed, FlowCode can also generate a hex and a C file. Simply click on "Chip" in the task - bar and from the drop down menu click on "Compile to HEX.." The project will now be saved in your HDD in hex format. Matrix Multimedia offers this posibility so as the FlowCode user will be able to use any third party programming device.
Anyway attached is the hex file that you asked for.
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PGA2310_PAN_5LATv4.hex
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis

Thanks for posting the hex file. I am currently experiencing problems with my FC5 as it currently won't compile any flowchart to hex for my programmer. I started experiencing problems with it after installing a new antivirus on my laptop but I am in the process of getting the problem fixed :)

Thanks again for posting the hex, I appreciate your help very much :D

phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis

Thanks for posting the hex file. I am currently experiencing problems with my FC5 as it currently won't compile any flowchart to hex for my programmer. I started experiencing problems with it after installing a new antivirus on my laptop but I am in the process of getting the problem fixed :)

Thanks again for posting the hex, I appreciate your help very much :D

phil
The upgraded fcf file that i posted is obtained with FC v4. Not with FC v5! Why you don't try with the current version of FlowCode that you own? It took me one day to write again the fcf in v4 because "Stanga" asked me it and i knew that you have only the FCv4 full working. Oh Phil! Please make your life easy :)
How is going with the remote control that you own? I have seen the kits in the web link you posted. Made in Hong Kong. You should believe just the half of those they refer :wink:
BTW, i have tried 3 universal remote controls with success. One of them i built by alone, using the Philips SAA3010 to transmit in address "16". The other is a Philips RC8530 and the third is a cheap that i bought from a kiosk for 3 Euros but works! Though not so good like the other two. I attach pictures.
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Mini-TV-Universal-Remote-Control.jpg
Mini-TV-Universal-Remote-Control.jpg (6.16 KiB) Viewed 10952 times
TEKO1112.jpg
TEKO1112.jpg (24.38 KiB) Viewed 10952 times
Philips RC8530.jpg
Philips RC8530.jpg (17.99 KiB) Viewed 10952 times
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi fotis,

Thanks for the advice :lol:

The copy of FC4 that I own is a student license and it only allows me to compile small flowcharts to hex as it has a limit. I upgraded to FC5 again keeping the student license but it didn't allow me to compile anything to hex because I had not activated it properly but I did get this fixed, although it does have a limit but it's not quite as restrictive as FC4 and it allows me to compile this project to hex. After renewing my antivirus some functions of FC5 have stopped working and some other software on my laptop has stopped working completely :( Hopefully I will have this fixed very soon.

Anyway I did compile your hex to chip and every remote I've tried does not work. A message "No Signal!" appears on the display. If it works on your project and not mine then there must be a problem on my circuit. I have checked my circuit against yours and so far I can't see a problem but I will be checking again tomorrow.

Thanks again

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi fotis,

Thanks for the advice :lol:

The copy of FC4 that I own is a student license and it only allows me to compile small flowcharts to hex as it has a limit. I upgraded to FC5 again keeping the student license but it didn't allow me to compile anything to hex because I had not activated it properly but I did get this fixed, although it does have a limit but it's not quite as restrictive as FC4 and it allows me to compile this project to hex. After renewing my antivirus some functions of FC5 have stopped working and some other software on my laptop has stopped working completely :( Hopefully I will have this fixed very soon.

Anyway I did compile your hex to chip and every remote I've tried does not work. A message "No Signal!" appears on the display. If it works on your project and not mine then there must be a problem on my circuit. I have checked my circuit against yours and so far I can't see a problem but I will be checking again tomorrow.

Thanks again

Phil
Hi Phil
I hope you will solve the problem of your Laptop ASAP. Regarding remote control issues and according to the message you receive "NO SIGNAL" i can think just two cases:
1) No one of your remote controls transmit in RC-5. By any way, when no signal received the program stores in the EEPROM of micro the address "0" which is the most common. Is the TV address code.
2) Perhaps you do something wrong during set-up. I repeat the correct way: Turn on the power and immediately press the MUTE button on micro PCB. When "INITIALISE REMOTE CONTROL" appears on display, press FIRMLY the MUTE button on remote control handset until you will see "ADDRESS = XX" on display. Only after this message you can release the button pressed.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis,

I think it's safe to say that the remote handsets I'm using aren't transmitting RC-5 comands. Are you familiar with those "One For All" handsets? You can control many devices from one remote - if you want to use it for controlling a tv you have to press the TV button and then press "Magic" type in a code which is in the instructions. Once typed in it stores the code in it's memory. If I were to type in a code so that it works with a philips device, do you think that it will transmit RC-5 commands?

Thanks

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

philip davies wrote:Hi Fotis,

I think it's safe to say that the remote handsets I'm using aren't transmitting RC-5 comands. Are you familiar with those "One For All" handsets? You can control many devices from one remote - if you want to use it for controlling a tv you have to press the TV button and then press "Magic" type in a code which is in the instructions. Once typed in it stores the code in it's memory. If I were to type in a code so that it works with a philips device, do you think that it will transmit RC-5 commands?

Thanks

Phil
I don't know for the "Magic", i have to study in detail. Instead those, i have to propose you this one for which I know that can do the job:

http://www.ebay.co.uk/itm/Philips-SRU30 ... 2eaee37f90
Buy it! Is Philips, is cheap and the seller is UK based, so you have to pay just 1.95 Pounds for P&PP.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis,

Thanks for finding that philips remote on ebay. I will be buying that as it's a philips device and so should work with this project. I will also be trying a "One For All" remote because I've found my one earlier this evening. I need to find the instructions for it although I could most probably find it on the internet. I will let you know if it works or not.

BTW I've also discovered this evening on the internet that a SKY+ remote can be set up to send RC-5 commands :)

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

Good morning Phil
I wish you success with remote controls. You know something? My problem is that no one of those universal remote controls - included Philips - can fulfil by 100% the demands of this project in which we have include e.g. the Balance function. Though there are RC-5 commands for Balance, this function is no handy or is absent on any universal handset. And we need a remotelly controlled Balance function, think about. For this reason 10 days ago i search to find a good "Blank" plastik box with small dimensions, in which i will include a programmed PIC to transmit in address "16" and thru 8 - 10 buttons will execute these functions: STBY, MUTE, CH+, CH-, VOL+, VOL-, BAL left, BAL right, maybe Loudness etc. All these functions should be remotelly managed.
BTW, from today i will start the proccess of your fcf, in the meantime i had some ideas i will try to implement in code. Also, from the past week i received two PIC16F1937 as samples from Microchip. These new mcu are pin to pin compatible with P16F887 but offer lot of new posibilities, like deeper stack level so will try these instead F887. Yesterday i had few money left over and by the chance i ordered from e-bay two rails of 10 common DPDT relays (OMRON G6A-234P-BS-5Volt, are very good for audio signals due to their "AgPd+Au clad" contacts, though their coils demand 16mA more than G6A-234P-ST-US that i used in the past). Total 20 pieces for 0.4 GBP/piece, very good price. Hey Phil, do you think that i am rich? :lol:
Last edited by fotios on Thu Feb 23, 2012 12:40 pm, edited 1 time in total.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

And a very good mornig to you to Fotis :)

I understand your problem with universall remote handsets, they tend to only cover bassic functions to control devices. I like the Idea of making my own handset, it can be customised to suit this project and not have a remote with loads of buttons but ending up with only a few of them actually working - like a "One For All" remote

Thanks for your time to look at the fcf file I sent you, I appreciate it very much :D

I have to be honest here - your wealth has never crossed my mind. Why do you ask? :lol:

Thanks again

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

That is a useful information about the properties of relay contacts:
Gold (Au) has better anti-corrosion properties than Silver (Ag)
Silver (Ag) presents better conductivity than Gold (Au)
Palladium (Pd) is the higher member of Platinum family (Pt).
Take a look and in wikipedia.
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Thanks Fotis, will be taking a look at that on wikipedia

Cheers

Phil

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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by fotios »

Phil here's one - in my opinion - good block diagram on which we will work. Includes everything you wanted plus a headphone amplifier. It is based on my long experience with professional mixing desks.
14 relays and 4 dual operational amplifiers needed. If you like to add or move something, please tell me your opinion. Any advice from other people will be also welcomed.
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MULTI PREAMP.jpg
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Re: Hi-Fi audio preamplifier using Burr-Brown PGA2310

Post by philip davies »

Hi Fotis,

The layout of your block diagram is exactly what I'm looking for. I like the Idea of having a relay to send the audio signal to the headphone amplifier. Will this relay be controlled via the MCU? if so it could be possible to have the display print "Headphones" on the bottom left corner when they are plugged in. I might be able to do that bit myself with the help of FC4 or FC5. I had thought about building a headphone amplifier into this preamp project as I have a nice circuit that I built some time ago and sounded excellent. I was also going to add a small circuit into the preamp that will switch off my power amplifier when a pair of headphones are connected into the headphone socket. As far as the REC OUT relays and INSERT LOOP relays are concerned, they don't need to be operated via the remote handset, it would be nice if they were but not essential.

I don't think i would need to add anything extra to your block diagram as it has covered exactly what I wanted :) nice work :D but I would move the MUTE relay so that it can work with either the headphones or the preamp output, at the moment the MUTE relay only works on the preamp output (if you see what I mean) and also move the output buffer amp so that its connected after the PGA2310. So in other words - PGA2310 output goes to the output buffer amp, from there it goes to the MUTE relay and from the MUTE relay to the HEADPHONES ON relay. If you see a potential problem with my change then let me know. I would like to ask, will connecting a graphic eq into the INSERT LOOP overload the PGA2310 input? My graphic does have level adjustments on it

I have also found a nice 24bit/192Khz DAC to install inside this project once it has been finished. It has 3 inputs - USB, Optical and Coaxial. I was thinking of making my own but I've seen plenty of kits available that will probably do the job quite nicely.

Thanks Fotis

Phil

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