PLL circuit with 3 IC's

Please tell me in detail which wire should go to which number (eg. A1, B2, C4 etc...).
I am in need of big help here. I don't know what else should be done to get this correct.
I have to build this PLL circuit and choose any 3 N (integer) of the N-divider. Then I have to observe the input signal Sig_in and the output signal VCO_out for each N. The result should be that the output frequency is N+1 times bigger than that of the frequency set by ELVIS (function generator), if I have understood the instructions correctly. I attached my results. The output signal looks weird, right? When I set N as 1, the output signal gets messed up :/ I tried for N= 4 and 8, the waveform looked just the same as when N=1. What should I do? By the way, where should I connect the 5th pin of IC 85 (A=B) to? In the diagram it just shows a short line not connecting to anything.
I took 4 pictures of different angles so you can see better.
http://www.flickr.com/photos/98820721@N04/11870437296/sizes/o/in/photostream/
http://www.flickr.com/photos/98820721@N04/11870033074/sizes/h/in/photostream/
http://www.flickr.com/photos/98820721@N04/11870445586/sizes/k/in/photostream/
http://www.flickr.com/photos/98820721@N04/11869882813/sizes/k/in/photostream/

Please keep everything in this thread. No one is going to try to debug the photos of your wiring shown in the other thread.
Do you understand how the 4046 works? When you have both R1 and R2 connected you have a limited range of frequencies from the VCO. Page 5 of the Fairchild datasheet for the 74HC4046 shows fmax/fmin no larger than 7.5 to 9.5 regardless of the ratio of R2/R1, depending on the value of Vcc. For R2 = R1 fmax/fmin ~ 1.7. So the circuit you have cannot possibly work for more than one value of N! Well, maybe it would work for a few closely spaced values at the high end of the range.
Study the datasheets. Decide what specifications you actually want to meet. Calculate the minimum and maximum frequencies at the VCO output. See if you can select values for the VCO and filter passive components which might work. Then try it.
Also, look at the logic design. I doubt it does what you expect. Try drawing a timing diagram manually and look at the A>B and A<B outputs.
When you are troubleshooting a PLL circuit, it is useful to look at the output of the phase detector or filter. That will tell you if it is trying to force the VCO to one extreme or the other. It will also tell you whether the signal is steady, oscillating periodically, or moving somewhat randomly. Each of those can be a clue as to what is going on. Also look at the A>B and A<B outputs of the comparator.
Lynn

Similar Messages

How to simulate a pll circuit with NI MULTISIM

I want to simulate a PLL circuit with Multisim 13.0 before building it on the real NI ELVIS 2 breadboard. I want to see what results I should be expecting first, but I couldn't find a 74HC4046 chip in the Multisim software. Does anyone know how I can find the 74hc4046 chip in that software?

Hi there,
When a component is not available in the Multisim Database, you can try to find a SPICE model for the component and then use the Component Wizard (Tools menu) to create a custom component. Click here to learn more about component creation.
Usually, SPICE models can be found in the manufacturer's website. I did a quick search but could not find a model for the 74HC4046.
In Multisim, there is a generic PLL that you could use. It can be found in the Mixed Group, MIXED_VIRTUAL family.
Regards,
Fernando D.
National Instruments

Multi-homing VPLS circuits with different carriers?

Hi,
I've got a nice VPLS implementation with 22 different sites, implemented by 1 carrier (let's call them carrierA).
The boss now wants to have a backup VPLS implementation with a second carrier (let's call them carrierB).
So the end result will be that we will have 2 separate VPLS implementations provided by 2 different carriers.
The million dollar question:
Is it possible to multi-home these things, so that if there is any failure of any of the VPLS lines provided by carrierA, it will fail-over to carrierB?
The hardware I've got at these sites are Catalyst 4500 and 3750 switches, as well as some ISRs.
Thanks!

You would rely on spanning-tree to find the best path. If one of your interfaces goes down then it should send traffic to the next available interface. The downfall of ethernet circuits is that the protocol or interface typically doesn't go down when there is an issue. The switch or router will show up/up but actual issues exists and traffic is just being dropped from carrier issues. For that reason I like to setup IP SLA.
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Counter and comparator circuit with hc393 and hc85

I searched for a full schematic for building a comparator circuit and counter circuit that are connected to each other, using ics hc393 and hc85 but couldnt find any. Can san someone send me a schematic of this circuit?

Hi aruwin,
Please have a look at this schematic:
HC393 ICs give us values from 0000 to 1111 (where QD is the most significant bit).
HC85 ICs has two 4-bit inputs (where A3 and B3 and the most significant bits) and compares them giving three digital outputs:
1. A > B
2. A = B
3. A < B
You might ask why there are 3 more inputs (A > B_I, A = B_I, A < B_I). Those are needed if you are working with 8-bit numbers.
In addition please have a look at this article for more detailed explanation:
http://www.electronics-tutorials.ws/combination/comb_8.html
Kind Regards,
Max
Applications Engineer
National Instruments

Workflow Circuit between FCP and After Effects with HDV

I am trying to set up a workflow circuit with FCP 5.1.1 and AE 7.0 using HDV. We are:
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2. exporting to AE
3. adding in FX with AE
4. putting those back into FCP
The footage we are using is compressed with HDV 1080i60 in FCP.
My problem is finding the correct way to export the HDV with FCP. I have tried using Quicktime Conversion but the only option I can find for uncompressed video didn't work when we tried to transfer it.
I think the main problem is that the AE work is being done on PCs and the video that we have tried sending can't be read by PCs. The audio plays through fine but the video shown is nonexistent.
What conversion should we use in FCP that allows us to keep the video uncompressed and in its best quality for use in AE? And what works best on the AE end of it?
Can someone give some advice on steps that they would or have taken for a project of the same ilk.
G5 Mac OS X (10.4.7)

What's your system setup? What FX exactly (e.g. color correction, or just random FX thrown in every now and then)? What went wrong when you tried using an uncompressed codec?
1) If everything's on an external FAT32 formatted drive (fat chance, get it?), then i think you could export a quicktime reference of your timeline (choose the option that ends up giving u a tiny file). Then plug the drive into your PC, load the Quicktime Ref (also known as QT Ref) into AE7 and FX away. Then export a QT with HDV 1080i60 specs and reimport into FCP.
2) If you're only doing occsional FX (e.g. gun flashes, lasers from robots, etc..), and nothing that encompasses the entire length of the project (e.g. color correction), you could export a hashed down QT Conversion of the timeline with whatever decent codec that works (e.g. DV NTSC). Then import into AE7, lay down the video, add your effects. But then before you export your FX, turn OFF your original video layer so all your FX are on a transparent background. Export clips with alpha channel and reimport those into FCP.
3) Ensure that the PC is using the latest version of quicktime. It may need to be upgraded to whatever version is on the Mac, and it may need to be registered as Pro.

PLL with the Ni 5411 Arb and PXI Star

I am trying to PLL the NI 5411 Arb with the PXI Star, but I have found no documentation indicating how to do it and it does not appear to happen automatically like some other devices. I currently have a 6608 timing card in the PXI Star Slot.

The PXI-5411 is capable of Phase-Lock Looping with the 10MHz Backplane clock and is capable of receiving a trigger signal from the PXI Star Trigger line. However, the PXI-5411 is not capable of driving the PXI Star Trigger.
For more information abotu how the PXI-5411 uses the PXI Trigger Lines, see the "RTSI/PXI Trigger Lines" part of "Chapter 2 - Arb Operation" in the User Manual of the board (linkes below).
NI 5411 User Manual
The Example program attached below (written under LabVIEW 6.1) shows how to synchronize two NI 5411 boards by first Phase-Lock Looping (PLL) their internal clocks with the 10MHz Backplane Clock provided by the chassis, and then sending a trigger line from one 5411 (the master board) to the other (the slave board).
If you want to receive the PXI Star Trigger as the Star Trigger, you will need to use a PXI board capable of sending a signal to this pin. The only NI PXI boards capable of sending a digital trigger pulse over the PXI Star Trigger line are the PXI-5112 (High Speed Digitizer) and the PXI-7344 (Motion).
The PXI-6608 board is not capable of driving the PXI Star Trigger line, however, if you install the PXI-6608 board in slot 2 of the PXI chassis, it will override the 10MHz clock signal provide by the PXI chassis, with the onboard OCXO 10MHz signal provided by the board itself. The PXI-6608 provides a 75 ppb accuracy 10MHz clock, that replaces the aproximately 50 ppm accuracy 10MHz clock provided by the PXI chassis. By overriding the 10MHz clock with a better accuracy one, the PXI-5411 boards will do PLL using a better reference clock.
The only device that PLL automatically with the 10MHz backplane clock are the PXI-6115 Simultaneous Sampling boards.
See related links for more information.
Hope this helps,
Claudia Lorente
Applications Engineer
National Instruments
http://www.ni.com/ask
Knowledge Base 2S2BFCQ7 : PXI Devices That Can Send and Receive Star Triggers
About Your 6608 Device
Knowledge Base 2NFGGQAL : OCXO Stability On The PXI-6608 Counter/Timer
Knowledge Base 2CCF38PQ : Accuracy Problems when I Drive the PXI Backplane Clock with a PXI-6608
Attachments:
5411_Synchronize_Generation.vi ‏229 KB

How to connect DAQ6013 with CB-68LPR with 555 timer

I need help to connect the CB-68LPR with 555 timer.
There is only input and a output
The input is V+,V- which is supply by a DC power supply
The output is output of the 555 timer.

Timer,
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NI 6013/6014
User Manual
Spencer S.

Guest Access with Inter-vlan Mobility

I have a setup as follows
Two datacenters each with one wlc5500, one guest access server and one internet circuit with firewall.
LWAPs connect to the data centres over a WAN.
Each LWAP has two SSIDs one guest with web auth and one private with 802.1x.
Site1 has 40 APs and site2 has 10 APs.
The best scenario would be to have 30 APs on each controller but this means that there would be a mix of APs centrally switched on different VLANs for the guest wlan.
Is there any way to anchor clients that intially associate to WLC1 so that if they roam on to WLC2 they keep the same IP address from datacentre 1. Similarly those that associate to WLC2 keep their IP from datacentre 2 if they roam to WLC1. Finally if either WLC1 or WLC2 fail then all clients re-associate to the active WLC at one DC. All the config guides so far only depict one internet circuit so I can't work out if this is possible yet. So far with both WLCs active the client changes address as they roam to the other WLC.
I would like to avoid creating a L2 link beween DCs if possible

Thanks for looking
(Cisco Controller) >show wlan 3
WLAN Identifier.................................. 3
Profile Name..................................... guest
Network Name (SSID).............................. GUEST
Status........................................... Enabled
MAC Filtering.................................... Disabled
Broadcast SSID................................... Enabled
AAA Policy Override.............................. Disabled
Network Admission Control
NAC-State...................................... Disabled
Quarantine VLAN................................ 0
Number of Active Clients......................... 0
Exclusionlist Timeout............................ 60 seconds
Session Timeout.................................. 1800 seconds
CHD per WLAN..................................... Enabled
Webauth DHCP exclusion........................... Disabled
Interface........................................ guest-vlan
WLAN ACL......................................... unconfigured
DHCP Server...................................... 10.18.227.10
DHCP Address Assignment Required................. Enabled
--More-- or (q)uit
Quality of Service............................... Silver (best effort)
Scan Defer Priority.............................. 4,5,6
Scan Defer Time.................................. 100 milliseconds
WMM.............................................. Allowed
Media Stream Multicast-direct.................... Disabled
CCX - AironetIe Support.......................... Enabled
CCX - Gratuitous ProbeResponse (GPR)............. Disabled
CCX - Diagnostics Channel Capability............. Disabled
Dot11-Phone Mode (7920).......................... Disabled
Wired Protocol................................... None
IPv6 Support..................................... Disabled
Passive Client Feature........................... Disabled
Peer-to-Peer Blocking Action..................... Disabled
Radio Policy..................................... 802.11b and 802.11g only
DTIM period for 802.11a radio.................... 1
DTIM period for 802.11b radio.................... 1
Radius Servers
Authentication................................ Global Servers
Accounting.................................... Global Servers
Dynamic Interface............................. Disabled
Local EAP Authentication......................... Disabled
Security
--More-- or (q)uit
802.11 Authentication:........................ Open System
Static WEP Keys............................... Disabled
802.1X........................................ Disabled
Wi-Fi Protected Access (WPA/WPA2)............. Disabled
CKIP ......................................... Disabled
Web Based Authentication...................... Enabled
ACL............................................. Unconfigured
Web Authentication server precedence:
1............................................... local
2............................................... radius
3............................................... ldap
Web-Passthrough............................... Disabled
Conditional Web Redirect...................... Disabled
Splash-Page Web Redirect...................... Disabled
Auto Anchor................................... Disabled
H-REAP Local Switching........................ Disabled
H-REAP Learn IP Address....................... Enabled
Client MFP.................................... Optional but inactive (WPA2 not configured)
Tkip MIC Countermeasure Hold-down Timer....... 60
Call Snooping.................................... Disabled
Roamed Call Re-Anchor Policy..................... Disabled
Band Select...................................... Disabled
Load Balancing................................... Disabled
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Mobility Anchor List
WLAN ID IP Address Status
(Cisco Controller) >?
(Cisco Controller) >show wln 3
Incorrect usage. Use the '?' or key to list commands.
(Cisco Controller) >
(Cisco Controller) >
(Cisco Controller) >
(Cisco Controller) >show wlan 3
WLAN Identifier.................................. 3
Profile Name..................................... guest
Network Name (SSID).............................. GUEST
Status........................................... Enabled
MAC Filtering.................................... Disabled
Broadcast SSID................................... Enabled
AAA Policy Override.............................. Disabled
Network Admission Control
NAC-State...................................... Disabled
Quarantine VLAN................................ 0
Number of Active Clients......................... 1
Exclusionlist Timeout............................ 60 seconds
Session Timeout.................................. 1800 seconds
CHD per WLAN..................................... Enabled
Webauth DHCP exclusion........................... Disabled
Interface........................................ guest-vlan
WLAN ACL......................................... unconfigured
DHCP Server...................................... 10.253.128.10
DHCP Address Assignment Required................. Enabled
--More-- or (q)uit
Quality of Service............................... Silver (best effort)
Scan Defer Priority.............................. 4,5,6
Scan Defer Time.................................. 100 milliseconds
WMM.............................................. Allowed
Media Stream Multicast-direct.................... Disabled
CCX - AironetIe Support.......................... Enabled
CCX - Gratuitous ProbeResponse (GPR)............. Disabled
CCX - Diagnostics Channel Capability............. Disabled
Dot11-Phone Mode (7920).......................... Disabled
Wired Protocol................................... None
IPv6 Support..................................... Disabled
Passive Client Feature........................... Disabled
Peer-to-Peer Blocking Action..................... Disabled
Radio Policy..................................... 802.11b and 802.11g only
DTIM period for 802.11a radio.................... 1
DTIM period for 802.11b radio.................... 1
Radius Servers
Authentication................................ Global Servers
Accounting.................................... Global Servers
Dynamic Interface............................. Disabled
Local EAP Authentication......................... Disabled
Security
--More-- or (q)uit
802.11 Authentication:........................ Open System
Static WEP Keys............................... Disabled
802.1X........................................ Disabled
Wi-Fi Protected Access (WPA/WPA2)............. Disabled
CKIP ......................................... Disabled
Web Based Authentication...................... Enabled
ACL............................................. Unconfigured
Web Authentication server precedence:
1............................................... local
2............................................... radius
3............................................... ldap
Web-Passthrough............................... Disabled
Conditional Web Redirect...................... Disabled
Splash-Page Web Redirect...................... Disabled
Auto Anchor................................... Disabled
H-REAP Local Switching........................ Disabled
H-REAP Learn IP Address....................... Enabled
Client MFP.................................... Optional but inactive (WPA2 not configured)
Tkip MIC Countermeasure Hold-down Timer....... 60
Call Snooping.................................... Disabled
Roamed Call Re-Anchor Policy..................... Disabled
Band Select...................................... Disabled
Load Balancing................................... Disabled
--More-- or (q)uit
Mobility Anchor List
WLAN ID IP Address Status
(Cisco Controller) >?

Convergence error in mosfet driver NCP5355D circuit, might be bootstrap mistake?

Hi there,
I'm using the Multisim 13.0.1. There's a 8-pin mosfet driver NCP5355D available in the library. I wanted to use it for switching half-bridge MOSFETs, but a simulation error has occured. The report said that 'Transient time point calculation did not converge'.
I've included the circuit with the gate driver, and also the circuit with separate pulsed voltage sources for switching MOSFETs, which could provide a general view of what I intended to achieve with the gate driver.
I also tried to configure the gate driver step by step- I started from the VS, CO, EN, PGND pins side and got no simulation errors then; but when I started connecting the BST and DRN pins, convergence error occurred. So is the convergence error resulting from any mistakes in connecting the BST and DRN pins?
To make it easier, the datasheet of NCP5355D is also attached here, where example application connections are included.
Expecting your insights and thanks in advance!
Solved!
Go to Solution.
Attachments:
cap2-test1_2clk.ms13 ‏183 KB
NCP5355-D.PDF ‏104 KB
cap2-test1_2clk_5355.ms13 ‏172 KB

I do not have Multisim so I cannot see your circuits but have some general observations.
1. MOSFET driver models often use switches and these can lead to convergence problems. This is because the switching action introduces a strong non-linearity into the model. I wrote my own model using transmission lines for delay and non-linear dependent sources with tanh functions rather than hard switches.
2. If you do not need to model the detailed behavior of the driver, using pulsed sources with rise/fall times as long as possible without changing the behavior of the MOSFETs might be a better choice.
3. There are books written on how to deal with SPICE convergence problems. This is what I found helpful from one of them:
** From Inside Spice by Kielkowski
** Convergence aids:
** Select appropriate RELTOL
** set VNTOL = RELTOL*Vsmall
** set ABSTOL = RELTOL*Ismall
** set GMIN = 1/Rp where Rp is parasitic resistance which
*** will have minimal effect when added to circuit.
** semiconductor models should have non-zero resistances
** RS (diode), RE, RC (BJT), RD, RS (FET)
** Raise ITL1=500 (DC OP iterations limit)
** use .NODESET
** use source stepping ITL6=500
** Transient convergence aids
** Add capacitance to device models:
** CJO (diode), CJE, CJC, CJS (BJT), CDG, CGS (JFET)
** CGDO, CGSO, CGBO, CBD, CBS, CJ, CJSW
** increase ITL4=40
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Lynn

Offset problem in simulating current and voltage phase relation of parallel rlc circuit, Is it a bug ?

tested multisim for Parallel RLC Circuit with voltage source as in
http://www.electronics-tutorials.ws/accircuits/parallel-circuit.html
But the current flows through the inductance L has DC component as in the picture attached (the red sine wave). Is it a bug ?, please tell me how to correct it.
Attachments:
phasor.jpg ‏183 KB

Hi there,
As strange as this may sound, this is not a bug. OK, this sounds really funny, but I am totally serious, and I am going to explain why:
In a circuit energy must be conserved.
An inductor is a purely reactive component, that is, it does not dissipate any power.
When simulation starts, Multisim assumes the inductor current to be 0, which may seem reasonable. The voltage across the inductor is also 0 at this point. This is the initial condition.
The voltage across the inductor increases, and thus, the current increases. The current keeps increasing during the first 2 quadrants of the sinusoidal phase output.
The current never decreases until the voltage drop is negative.
But by the time an entire cycle is over, the current is back to 0. This makes sense as energy is conserved and the inductor is not absorbing any energy.
OK. Now look at what happened. During the whole cycle, the current was positive only! The current increased during the first half of the cycle and returned to 0 during the second half. This is because of the fluke of initial conditions! In fact, a good circuit simulator will maintain the DC offset for a long duration. The DC offset may drift because of rounding errors and the like.
This will never be observed in real life as real inductors have winding resistance and other problems.
OK, so, if you would like to see no DC offset, do the following:
Run your simulation
Record the DC offset that you want to eliminate
Stop your simulation
Double click the offending inductor in the Multisim schematic
Click on the Value tab
Check the Initial conditions box under Additional SPICE simulation parameters
Enter the negative of the DC offset that you recorded in step 2 into the box right next to it
Start your simulation. Did your offset go away? Or did it double?
If your offset doubled, take away the sign from the DC offset that you entered in step 7. I bet you know why.
It took me a while to figure this one out. Hope that helps!
Yi
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I have to replace cisco equipmenet and looking for an advise
my current network layout:
my destination layout want to something like that:
I have a couple questions:
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Convert a circuit from UPSR to unprotect on 15454s(MSPP)

Hi,
we are implementing ONS 15454 SONET(MSPP) network. And Is there any method to convert a UPSR circuit(VT/STS) to unprotect on ONS15454/15310(Rel 6.0) by using CTC/TL1 without service interruption? Appreciate your expert advice.

As Todd indicated, in release 6.0 there is a bridge and roll feature; you can upgrade an unprotected circuit to a fully protected circuit or downgrade a fully protected circuit to an unprotected circuit with the exception of a UPSR circuit. When using bridge and roll on UPSR circuits, you can roll the source or destination or both path selectors in a dual roll. However, you cannot roll a single path selector.
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How to make Self stopping Counter with Multisim?

Please help me to make Self Stopping Counter with multisim.
Attachments:
Make Self stopping Counter Circuit with Output as.doc ‏188 KB

Hi,
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Tien P.
National Instruments

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I am working for a company that has two Internet circuits with different ISPs at two different locations for redundancy, and both Internet circuits run at different speeds. I'd like to be able to direct the majority (but not all) of the traffic through the ISP with the larger bandwith, but then failover all traffic to one ISP when the other goes down. We're currently using the "default-information originate" command, which fails over OK, but I haven't figured out how to do the load balancing. I'd appreciate your thoughts. Thank you.

One thing that you could consider is advertising the default route as and
external 1 route instead of an external 2 route(cisco default). If you advertise it as an E1
route, all routers will take into consideration the cost associated with the
default route to the router advertising the default route plus the cost of the
default route itself. Whereas if it is an E2 route, the routers just use the
cost associated with the external cost and not the path to get to the router
advertising the default route.
If you made the default route E1, then the routers closest to the advertised
routers will prefer the closest default route and their preference could then be
tweaked by adjusting the interface costs for the default route with a routemap.
By using this method, you could then control which routers use which internet
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router ospf 1
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Large analogue input noise with laptop and 6024

Acquiring an analogue signal leads to large noise of +-100mV !
I'm using a NI 6024 card with shielded cable and a selfbuild connector box on a Dell D800 Laptop. The analogue inputs are used as differential inputs and connected to external amplifiers. In the box additionally the frequency output (GPCTR0_OUT and DGND) is connected to a small electronic circuit with an octal buffer (74HCT250) and 5V voltage regulator (An external 12V power supply is additionally used).
The noise is not reduced by connecting V_IN- directly or via 10k resistor to AIGIND.
There is no noise, if a battery is connected to the analogue input.
May I e.g. connect the DGND to the AIGND ?
I would be happy to receive any suggestions for solving
this problem.
Thanks a lot
Ralf

Hi Ralf,
When using laptops and external circuitry there's always a whole lot of noise generated by the conflicting coupling of the laptop's power source and your external source. You might find that using the external power supply but powering the laptop from the battery also helps. I'd suggest that first you make sure that your laptop and circuitry are powered from the same electric line, then you can connect your external digital ground to the AIGround via a 10K resistor, to protect the DAQ board. This will help, but I believe the best way will be to use a low pass filter between your amplifier and your Analog Input, that way you'll be able to get rid of most of the high frequency noise.
In general, if you have an external digital circuit powered by an e
xternal power source and you're using a laptop I recommend you use opto-couplers, powered by the 5V of the DAQ card to get rid of any possibility of noise.

PLL circuit with 3 IC's

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