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View all threadsExtra ADCs and DACs on N210
Hello,
I was having a look at the schematics of the N210 and I found that there
are an extra ADC and two DACs for the RX and TX channels, in addition to
the mail 2 channel ADC for RX and DAC for TX. The chips are the AD56x3,
AD79x2, and MCP4922 visible on page 4 of the schematics.
One strange thing is that the output of the MCP4922 and of the AD56x3
seem to be connected to the same outputs.
What are those used for? The outputs are routed to the daughter board
interface, I had a look at the LFTX schematics and there they are simply
available on one of the connectors. Are they used in the more advanced
daughter boards?
Do I have access to them without modifying the FPGA code?
More generally, does it exist somewhere a block diagram of the N210
hardware?
Thanks. Best,
Daniele
Daniele,
The auxiliary DACs could be used if you were utilizing the main DAC output
channels as I & Q inputs to a modulator up front to remove any DC
offset/imbalance between the two. See pg47 of the AD9777 datasheet for an
example.
I imagine the AD56x3 and the MCP4922 are a population option.
Cheers,
Eric
On Wed, Jun 25, 2014 at 12:57 PM, Daniele Nicolodi via USRP-users <
usrp-users@lists.ettus.com> wrote:
Hello,
I was having a look at the schematics of the N210 and I found that there
are an extra ADC and two DACs for the RX and TX channels, in addition to
the mail 2 channel ADC for RX and DAC for TX. The chips are the AD56x3,
AD79x2, and MCP4922 visible on page 4 of the schematics.
One strange thing is that the output of the MCP4922 and of the AD56x3
seem to be connected to the same outputs.
What are those used for? The outputs are routed to the daughter board
interface, I had a look at the LFTX schematics and there they are simply
available on one of the connectors. Are they used in the more advanced
daughter boards?
Do I have access to them without modifying the FPGA code?
More generally, does it exist somewhere a block diagram of the N210
hardware?
Thanks. Best,
Daniele
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Daniele,
The auxiliary ADCs and DACs are used on some of the daughterboards like the
RFX-series. They are not used on the Basic, LF, or WBX/SBX/CBX.
Only one of the MPC4922 and AD56x3 are populated, but they are compatible
functionally. The AD56x3 was difficult to obtain.
Matt
On Wed, Jun 25, 2014 at 6:57 PM, Daniele Nicolodi via USRP-users <
usrp-users@lists.ettus.com> wrote:
Hello,
I was having a look at the schematics of the N210 and I found that there
are an extra ADC and two DACs for the RX and TX channels, in addition to
the mail 2 channel ADC for RX and DAC for TX. The chips are the AD56x3,
AD79x2, and MCP4922 visible on page 4 of the schematics.
One strange thing is that the output of the MCP4922 and of the AD56x3
seem to be connected to the same outputs.
What are those used for? The outputs are routed to the daughter board
interface, I had a look at the LFTX schematics and there they are simply
available on one of the connectors. Are they used in the more advanced
daughter boards?
Do I have access to them without modifying the FPGA code?
More generally, does it exist somewhere a block diagram of the N210
hardware?
Thanks. Best,
Daniele
USRP-users mailing list
USRP-users@lists.ettus.com
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
Hello,
thank you all for the answers! Things are clear now and are indeed
working as I thought. Still, it would be nice to have a block diagram
of the hardware functionalities of the device [0].
I'm planning to use it as a general-purpose data acquisition device (we
bought quite a few N210 in the lab and a collection of daughter boards)
and those "hidden" features may be very useful in some experiments (as
low frequency control and acquisition channels) especially if there
would be a easy way to interface with them from python code.
Cheers,
Daniele
[0] I may find the time to put together one myself and send it to the
list for review. But do not hold your breath for it...
On 26/06/2014 11:40, Matt Ettus wrote:
Daniele,
The auxiliary ADCs and DACs are used on some of the daughterboards like
the RFX-series. They are not used on the Basic, LF, or WBX/SBX/CBX.
Only one of the MPC4922 and AD56x3 are populated, but they are
compatible functionally. The AD56x3 was difficult to obtain.
Matt
On Wed, Jun 25, 2014 at 6:57 PM, Daniele Nicolodi via USRP-users
<usrp-users@lists.ettus.com mailto:usrp-users@lists.ettus.com> wrote:
Hello,
I was having a look at the schematics of the N210 and I found that there
are an extra ADC and two DACs for the RX and TX channels, in addition to
the mail 2 channel ADC for RX and DAC for TX. The chips are the AD56x3,
AD79x2, and MCP4922 visible on page 4 of the schematics.
One strange thing is that the output of the MCP4922 and of the AD56x3
seem to be connected to the same outputs.
What are those used for? The outputs are routed to the daughter board
interface, I had a look at the LFTX schematics and there they are simply
available on one of the connectors. Are they used in the more advanced
daughter boards?
Do I have access to them without modifying the FPGA code?
More generally, does it exist somewhere a block diagram of the N210
hardware?
Thanks. Best,
Daniele
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