Looking for spice model of ICM7555 cmos timer

[jerryjog]

555 timer pspice model

Friends,

I'm looking for spice model of ICM7555 cmos timer because I want to do some board level simulation using protel DXP. Does anybody have it. I downloaded a couple of files from internet but they don't seem to be correct. Thanks!

Jerry

 

[DrBob13]

555 spice model

Have you Tried this one from
http://www.ecircuitcenter.com/Circuits/555_Timer1/555_timer1.htm?

555_TIMER1.CIR - ASTABLE MODE
*
VCC 1 0 5V
*
* EXTERNAL TIMING COMPONENTS
RA 1 2 1K
RB 2 3 10K
C1 3 0 100PF
*
* DISCHARGE TRANSISTOR
Q1 2 6 0 QNOM
RBQ 15 6 15K
*
* 1/3 AND 2/3 VCC DIVIDER
R1 1 4 5K
R2 4 5 5K
R3 5 0 5K
*
* COMPARATORS
XCMP1 3 4 11 COMP1
XCMP2 5 3 12 COMP1
*
* RS FLIP-FLOP
XNOT1 11 13 1 NOT
XNOT2 12 16 1 NOT
XNAND1 13 14 15 1 NAND
XNAND2 15 16 14 1 NAND
*
* SUBCIRCUITS AND MODELS ***********************************
*
.SUBCKT NAND 1 2 3 4
* TERMINALS A B OUT VCC
RL 3 4 500
CL 3 0 10PF
S1 3 5 1 0 SW
S2 5 0 2 0 SW
.ENDS
*
.SUBCKT NOT 1 3 4
* TERMINALS A OUT VCC
RL 3 4 500
CL 3 0 10PF
S1 3 0 1 0 SW
.ENDS
*
*
.SUBCKT COMP1 1 2 5
* TERMINALS: 1-INPUT+, 2-INPUT-, 5-OUTPUT
* DIFF AMP WITH HYSTERESIS
EDIFF 3 0 VALUE = { V(1) - V(2) + V(5)/500 }
* FREQUENCY RESPONSE
RP1 3 4 200
CP1 4 0 100PF
* LIMITER
EOUT 5 0 TABLE {V(4)} = (-1MV 0V) (1MV, 5V)
.ENDS
*
*
.MODEL SW VSWITCH(VON=3 VOFF=2 RON=10 ROFF=100K)
.model QNOM NPN(BF=100)
*
* ANALYSIS *************************************************
.TRAN 0.05US 5US UIC
.IC V(15)=0V V(14)=5V V(3)=0V
*
* VIEW RESULTS *********************************************
.PRINT TRAN V(3) V(14)
.PROBE
.END

Or more are here
**broken link removed**

Bob.

 

[jerryjog]

icm7555

Thank you!
I'll definitely try it out.
One question though, since this 555 timer is just one of the modules of a big cirucit, should I attach .ckt file (spice subcircuit) as the model file for the timer? The files I found on the web all have .LIB extension... and the file you presented here is a .cir file. How do I create .ckt or it's not necessary? Sorry I've never used protel to do simulations before.

 

[DrBob13]

555 timer spice

Hi,
If you are using P*otel to do your simulation the 555 circuit is already built in to the package, find the Timer.lib which is in the simulation parts library.
Add the Sim.ddb into your project and then browse the libraries to find Timer.lib, then you can drag the UA555 part into your schematic and simulate it as usual.
The .ckt file is buried inside the LIB file in P*otel, it is possible to make up a part using the .ckt or.cir files but it is a bit tricky as P*otel does not use absolutely standard SPICE circit files.
P*otel 99 is my weapon of choice for all analogue circuit development, although you sometimes have to fiddle about with the conditions to get it to run OK.
Bob.

 

[jerryjog]

spice icm7555

Thanks for your reply.
Actually I'm modifying a circuit that may have durability issues and I particularly want to simulate ICM7555 because it's in the circuit. I'm more interested in the performance rather than functionality of the timer. I want to get into really detailed DC and Transient simulations like what we can do in Cadence. I appreciate your advice but can you let me know what the "trick" is?

 

[DrBob13]

icm7555 in pspice

There is a model specific to that device on the Maxim site.
**broken link removed**
I hope this helps you.
You should be able to do the parametric analysis you need with Protel, this simulator works in mixed signal mode at a higher level than just a simple logic sim, you can do DC and transient analysis with it OK, I am not very familiar with the current Cadence software as I have not used that package for over 7 years now.
Sorry that I underestimated the level of your query.
Regards.
Bob.

 

[max0412]

spice model for 555 timer

The TLC555 low power cmos timer model is included with Pspice.This is the same as the ICM7555 timer from Infineon ,according to the ICM7555 data sheet.

Get the model and datasheet on the TLC555 here.

http://focus.ti.com/docs/prod/folders/print/tlc555.html