Be warned that TI has discontinued this part with NO warning. Standard procedure is to indicate a part is not going to be available after a certain date and marking it as "Not Recommended For New Designs".
Instead TI has simply dropped it without warning. Here is the message that TI sent me in response to my inquiry.
________________________________
Dan,
Thank you for contacting the Product Information Center at Texas Instruments. My apologies for the delayed response. The part DIR1703 is not recommended for new designs and the product group chose to remove all information from the external website. There are plans for new design and support models for the DIR parts in the future but unfortunately this does not include DIR1703. At this time there is no information as to a replacement for this device. We apologize for any inconvenience this may cause and if there is anything else that we can help you with, please let us know.
Regards,
Rodney Brown
Texas Instruments
Semiconductor Technical Support
http://www-k.ext.ti.com/sc/technical_support/pic/americas.htm
_______________________________________
I can't blame this guy. He's just a spear carrier. However, I asked him to tell the powers that be at TI thank you for pointing out that TI is not a reliable supplier and that we should look elsewhere for our semiconductor needs.
In my case I had several products in development that used this chip, some of which were sold already and now I have to do them all over using a Cirrus chip. Tens of thousands of dollars of engineering work is out the window.
So be warned. TI cannot be trusted to give warning when a device is to be pulled. It looks like the TAS5015 PWM chip met the same fate too.
Instead TI has simply dropped it without warning. Here is the message that TI sent me in response to my inquiry.
________________________________
Dan,
Thank you for contacting the Product Information Center at Texas Instruments. My apologies for the delayed response. The part DIR1703 is not recommended for new designs and the product group chose to remove all information from the external website. There are plans for new design and support models for the DIR parts in the future but unfortunately this does not include DIR1703. At this time there is no information as to a replacement for this device. We apologize for any inconvenience this may cause and if there is anything else that we can help you with, please let us know.
Regards,
Rodney Brown
Texas Instruments
Semiconductor Technical Support
http://www-k.ext.ti.com/sc/technical_support/pic/americas.htm
_______________________________________
I can't blame this guy. He's just a spear carrier. However, I asked him to tell the powers that be at TI thank you for pointing out that TI is not a reliable supplier and that we should look elsewhere for our semiconductor needs.
In my case I had several products in development that used this chip, some of which were sold already and now I have to do them all over using a Cirrus chip. Tens of thousands of dollars of engineering work is out the window.
So be warned. TI cannot be trusted to give warning when a device is to be pulled. It looks like the TAS5015 PWM chip met the same fate too.
I'm surprised the tech support guy didn't send you a copy of the letter TI released when they discontinued this part. I can't find a link to it off the top of my head, but the gist of it was that the part had at least one fairly serious flaw where it would often refuse to sync to an new sample rate after having synced to an earlier one. I've also heard from someone who was using the part that it was quite flaky as to what signals it would accept. He had several customers complain that they couldn't get the receiver to sync with their CD players.
Of course, this doesn't excuse TI's behavior. The supply should not have been cut off so quickly, regardless of how severe the flaws were.
Of course, this doesn't excuse TI's behavior. The supply should not have been cut off so quickly, regardless of how severe the flaws were.
Yes... it appears that TI no longer makes digital interface receivers. Honestly, i'm not surprised.
The DIR1703 chip's data sheet is *painful* to read; I can't make much sense out of it, except that the chip doesn't have much going for it... I could be completely wrong in my following statements, but I blame the datasheet for that 😀
The Crystal CS841x parts are a joy to use. They integrate an internal RS422 receiver and a MUX, and don't require any external crystals. And they'll recover a clock from any signal you feed them - the '8416 is happy from 32 to 192KHz and anything in between.
But the DIR1703 doesn't include a receiver, and needs an external crystal or some other clock source attached to it. And from the looks of things, you can make the chip decode 44.1/88.2 or 32/48/96, not both. I suppose you could use two crystals or another PLL to make it support both rates, but that makes the chip even more complicated to use. And what's the point? is the recovered clock of the "SpAct"-equipped chip so much better to justify the extra complication?
Obviously I haven't designed it into anything. Wouldn't surprise me if the chip disappeared just because few people were buying it.
TI makes great stuff. I'm just hoping that the next digital audio interface receiver that they come out with is far better than this one...
The DIR1703 chip's data sheet is *painful* to read; I can't make much sense out of it, except that the chip doesn't have much going for it... I could be completely wrong in my following statements, but I blame the datasheet for that 😀
The Crystal CS841x parts are a joy to use. They integrate an internal RS422 receiver and a MUX, and don't require any external crystals. And they'll recover a clock from any signal you feed them - the '8416 is happy from 32 to 192KHz and anything in between.
But the DIR1703 doesn't include a receiver, and needs an external crystal or some other clock source attached to it. And from the looks of things, you can make the chip decode 44.1/88.2 or 32/48/96, not both. I suppose you could use two crystals or another PLL to make it support both rates, but that makes the chip even more complicated to use. And what's the point? is the recovered clock of the "SpAct"-equipped chip so much better to justify the extra complication?
Obviously I haven't designed it into anything. Wouldn't surprise me if the chip disappeared just because few people were buying it.
TI makes great stuff. I'm just hoping that the next digital audio interface receiver that they come out with is far better than this one...
Using the DIR1703
On the contrary, I designed the 1703 into several products and I found it very easy to use. Yes, the data sheet was confusing but the engineers at TI were helpful getting over a rough spot or two. But when building a dumb receiver, where it went straight to a D/A converter, the DIR1703 needed far less external support. The CS8414 I had difficulty figuring out.
And, the DIR1703, has no problem taking a signal from 32KHz to 96KHz and simply spitting out the I2S audio from it as well as all the necessary clocks. And I could use it as the master clock generator for the system as well. It also had a single pin I could use to switch the de-emphasis/emphasis on or off when switching between a 48K and 96K input.
The Cirrus chip needs gating to decode three lines to make this determination. The CS841x series was really meant to work with an external microcontroller while the DIR1703 was designed to work just as well in a stand alone mode.
If anyone has a basic stand alone receiver circuit for the CS8414 figured out to take between 44.1K and 96K input, please post it.
On the contrary, I designed the 1703 into several products and I found it very easy to use. Yes, the data sheet was confusing but the engineers at TI were helpful getting over a rough spot or two. But when building a dumb receiver, where it went straight to a D/A converter, the DIR1703 needed far less external support. The CS8414 I had difficulty figuring out.
And, the DIR1703, has no problem taking a signal from 32KHz to 96KHz and simply spitting out the I2S audio from it as well as all the necessary clocks. And I could use it as the master clock generator for the system as well. It also had a single pin I could use to switch the de-emphasis/emphasis on or off when switching between a 48K and 96K input.
The Cirrus chip needs gating to decode three lines to make this determination. The CS841x series was really meant to work with an external microcontroller while the DIR1703 was designed to work just as well in a stand alone mode.
If anyone has a basic stand alone receiver circuit for the CS8414 figured out to take between 44.1K and 96K input, please post it.
Chip pericles
Hi Dan, I agree the policy of TI is extremely unfortunate and blunt. But did you have good results with your prototype and this DIR1703 chip? I would go for the AD receiver. The CS8412 had also all kinds of problems in the old days and only really sings if you do a lot in front of it and a better PLL filter and analog supply and.........😎
Hi Dan, I agree the policy of TI is extremely unfortunate and blunt. But did you have good results with your prototype and this DIR1703 chip? I would go for the AD receiver. The CS8412 had also all kinds of problems in the old days and only really sings if you do a lot in front of it and a better PLL filter and analog supply and.........😎
Re: Chip pericles
Hi Elso,
I didn't know AD (presumably Analog Devices) made a receiver chip. Do you have a part number?
Receivers must be fairly difficult to make, because not many people make them! I've done a project using one of the AKM receivers and was very pleased with the part, the data sheet, and the results. One good thing about TI entering the market was that it forced Crystal to lower their formerly outrageous prices.
Best regards,
Charles Hansen
Elso Kwak said:
Hi Elso,
I didn't know AD (presumably Analog Devices) made a receiver chip. Do you have a part number?
Receivers must be fairly difficult to make, because not many people make them! I've done a project using one of the AKM receivers and was very pleased with the part, the data sheet, and the results. One good thing about TI entering the market was that it forced Crystal to lower their formerly outrageous prices.
Best regards,
Charles Hansen
Re: Re: Chip pericles
Charles, check out the AD1892, it's a receiver with ASRC intergrated. Maybe it's this part Elso is referring to.
Cheers, Tino
Charles Hansen said:
Charles, check out the AD1892, it's a receiver with ASRC intergrated. Maybe it's this part Elso is referring to.
Cheers, Tino
Re: Re: Chip pericles
Hi Charles,
Yes I meant the Analog Devices part AD1892. Unfortunately that one is also near obsolescence now. It is an integrated receiver/sample rate converter.
Do you have a source for the AKM part for us lower echelon mortals? (not OEM)
Charles Hansen said:
Hi Charles,
Yes I meant the Analog Devices part AD1892. Unfortunately that one is also near obsolescence now. It is an integrated receiver/sample rate converter.
Do you have a source for the AKM part for us lower echelon mortals? (not OEM)
Don't get me started on Crystal RX chips........
Especially the input stage. You can take that RS422 stuff and shove it.
Jocko
Especially the input stage. You can take that RS422 stuff and shove it.
Jocko
Re: Don't get me started on Crystal RX chips........
Jocko, Thanks for the enlightment!😉
Jocko Homo said:
Jocko, Thanks for the enlightment!😉
Re: Re: Re: Chip pericles
Hello Elso -
I'm not a big fan of sample rate converters. The idea of altering the original data doesn't sit too well with me.
In the US, AKM is only sold through one relatively small distributor. I'm not sure what their minimums are, but probably $50 or $100 I would guess. There is no Digikey or equivalent for AKM. I'm sure you've already seen the page for Europe at:
http://www.asahi-kasei.co.jp/akm/en/cpnydata/euro_sr.html
I would guess that you could probably get a sample or two from your local sales representative.
Good luck,
Charles Hansen
Elso Kwak said:
Hello Elso -
I'm not a big fan of sample rate converters. The idea of altering the original data doesn't sit too well with me.
In the US, AKM is only sold through one relatively small distributor. I'm not sure what their minimums are, but probably $50 or $100 I would guess. There is no Digikey or equivalent for AKM. I'm sure you've already seen the page for Europe at:
http://www.asahi-kasei.co.jp/akm/en/cpnydata/euro_sr.html
I would guess that you could probably get a sample or two from your local sales representative.
Good luck,
Charles Hansen
DIR1703 availability
I heard from a TI sales rep that the DIR1703 may still be available on special order for a while but a rep will have to ask. My rep works for Insight Electronics in Irvine CA.
More details Monday.
I heard from a TI sales rep that the DIR1703 may still be available on special order for a while but a rep will have to ask. My rep works for Insight Electronics in Irvine CA.
More details Monday.
DIR1703 still available
Here is some info dug up by my TI sales rep.
"The part is still available, just not on the web anymore to discourage new design-ins. The DIR1703 (and DIR1701) has a problem with losing lock if the sample rate changes. "
Here is more detail
Subject: DIR1701 and DIR1703 UNLOCK problem
Summary of Problem and Proposed Solution
The DIR1701 and DIR1703 are not recommended for new designs. The DIR1701/DIR1703 digital audio
interface receiver is unable to properly lock onto S/PDIF audio data that is encoded at more than one
sampling frequency. To lock onto the new sampling frequency, the DIR1701/DIR1703 must be reset using
an external control device, such as a microcontroller or DSP. If the sampling frequency of the encoded
audio data never changes, however, the DIR1701/DIR1703 will lock onto S/PDIF signals correctly.
Detailed Description
When the sampling frequency changes, the DIR1701/DIR1703 unlock and fail to re-lock at the new sampling
rate. In general, during normal operation an S/PDIF receiver outputs an UNLOCK flag when the sampling
frequency of the S/PDIF data changes. After the receiver has locked to the new sampling frequency, the
device outputs a LOCK flag. The DIR1701/DIR1703 is unable to correctly re-lock onto the new sampling
frequency. Specifically, after the sampling frequency changes the LRCKO output becomes unstable and can
create noise that will be passed through an audio DSP or audio DAC.
To lock onto a new sampling frequency, the DIR1701/DIR1703 requires an external reset signal every time
the S/PDIF audio sampling frequency changes. A microcontroller or DSP would typically be required to
provide this reset signal in a system.
I find this odd because when I designed a stand alone S/PDIF-AES/EBU receiver with analog out, I could change the sample rate between 44.1K to 96K and the device appeared to stay locked in all the time. I used the LOCK/UNLOCK output to drive an LED to act as a signal present indicator. It tracked changes perfectly. I did it dozens of times, switching the data rate on my source. However, after making the change I did not check for noise so that may be a problem. But then I was clocking it at double the normal frequency, at 24.576 MHz instead of the more common 12.288 MHz so I don't know if this makes a difference.
However, I feel that in most applications the data rate never changes. The device is connected to a source that stays at the same data rate all the time.
If anyone is interested I could post the files sent by TI.
Here is some info dug up by my TI sales rep.
"The part is still available, just not on the web anymore to discourage new design-ins. The DIR1703 (and DIR1701) has a problem with losing lock if the sample rate changes. "
Here is more detail
Subject: DIR1701 and DIR1703 UNLOCK problem
Summary of Problem and Proposed Solution
The DIR1701 and DIR1703 are not recommended for new designs. The DIR1701/DIR1703 digital audio
interface receiver is unable to properly lock onto S/PDIF audio data that is encoded at more than one
sampling frequency. To lock onto the new sampling frequency, the DIR1701/DIR1703 must be reset using
an external control device, such as a microcontroller or DSP. If the sampling frequency of the encoded
audio data never changes, however, the DIR1701/DIR1703 will lock onto S/PDIF signals correctly.
Detailed Description
When the sampling frequency changes, the DIR1701/DIR1703 unlock and fail to re-lock at the new sampling
rate. In general, during normal operation an S/PDIF receiver outputs an UNLOCK flag when the sampling
frequency of the S/PDIF data changes. After the receiver has locked to the new sampling frequency, the
device outputs a LOCK flag. The DIR1701/DIR1703 is unable to correctly re-lock onto the new sampling
frequency. Specifically, after the sampling frequency changes the LRCKO output becomes unstable and can
create noise that will be passed through an audio DSP or audio DAC.
To lock onto a new sampling frequency, the DIR1701/DIR1703 requires an external reset signal every time
the S/PDIF audio sampling frequency changes. A microcontroller or DSP would typically be required to
provide this reset signal in a system.
I find this odd because when I designed a stand alone S/PDIF-AES/EBU receiver with analog out, I could change the sample rate between 44.1K to 96K and the device appeared to stay locked in all the time. I used the LOCK/UNLOCK output to drive an LED to act as a signal present indicator. It tracked changes perfectly. I did it dozens of times, switching the data rate on my source. However, after making the change I did not check for noise so that may be a problem. But then I was clocking it at double the normal frequency, at 24.576 MHz instead of the more common 12.288 MHz so I don't know if this makes a difference.
However, I feel that in most applications the data rate never changes. The device is connected to a source that stays at the same data rate all the time.
If anyone is interested I could post the files sent by TI.
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