|* the [Model] Polarity specification such that the pin in the
|* [Diff_pin] column will be Non-Inverting and the pin in the
|* inv_pin column will be Inverting. This convention allows
|* one [Model] to be used for both pins.
|*
|* Column length limits are:
|* [Diff_Pin] 5 characters max
|* inv_pin 5 characters max
|* vdiff 9 characters max
|* tdelay_typ 9 characters max
|* tdelay_min 9 characters max
|* tdelay_max 9 characters max
|*
|* Each line must contain either four or six columns. If "NA" is
|* entered in the vdiff, tdelay_typ or tdelay_min columns, its
|* entry will be interpreted as 0V or 0ns. If "NA" appears in
|* the tdelay_max column, its value will be interpreted as the
|* tdelay_typ value. When using six columns, the headers
|* tdelay_min and tdelay_max must be listed. Entries for the
|* tdelay_min column are based on minimum magnitudes; and
|* tdelay_max column, maximum magnitudes. One entry of vdiff
|* regardless of its polarity is used for difference magnitudes.
|*---------------------------------------------------------------------------
[Diff_Pin] inv_pin vdiff tdelay_typ tdelay_min tdelay_max
|*
3 4 150mV -1ns 0ns -2ns | Input or I/O pair
7 8 0V 1ns NA NA | Output* pin pair
9 10 NA NA NA NA | Output* pin pair
16 15 200mV 1ns | Input or I/O pin pair
20 19 0V NA | Output* pin pair, tdelay = 0ns
22 21 NA NA | Output*, tdelay = 0ns
| * Could be Input or I/O with vdiff = 0V
|******************************************************************************
|==============================================================================|
| Keyword: [Model] |
| Required: Yes |
| Description: Used to define a model, and its attributes. |
| Sub-Params: Model_type, Polarity, Enable, Vinl, Vinh, C_comp |
|*
|* BIRD7.2 and 9.3 modifications
|* Usage Rules: Each Input, Output, I/O, 3-state, Open_drain, I/O_open_drain,
|* Open_sink, I/O_open_sink, Open_source, I/O_open_source,
|* Input_ECL, Output_ECL, I/O_ECL and Terminator model must
|*
| begin with the keyword [Model]. The model_name must match |
| the one that is listed under the [Pin] keyword and must not |
| contain more than 20 characters. An .ibs file must contain |
| enough [Model] keywords to cover all of the model_names |
| specified under the [Pin] keyword, except for those |
| model_names which use reserved words (POWER, GND and NC). |
| Model_names with reserved words are an exception and |
| they do not have to have a corresponding [Model] keyword. |
| C_comp is allowed to use "NA" for the min and max values only. |
|*
|* BIRD2.2 addition
|* The model types Input, I/O, I/O_open_drain, I/O_open_sink,
|* I/O_open_soure must have Vinl and Vinh defined. If
|* they are not defined, the parser will issue a warning and the default
|* values of Vinl=.8V and Vinh=2.0V will be assumed.
|*
|* The model types Input_ECL and I/O_ECL must have Vinl and Vinh defined. If
|* they are not defined, the parser will issue a warning and the default
|* values of Vinl=-1.475V and Vinh=-1.165V will be assumed.
|*
|* BIRD9.3 change
|* Other Notes: A complete [Model] description normally contains the following
|* keywords: [Voltage range], [Pullup], [Pulldown], [GND_clamp],
|* [POWER_clamp], [Rgnd], [Rpower], [Rac], [Cac],
|* and [Ramp]. However, some models may have only
|* a subset these keywords. For example, an input structure
|* normally only needs the [Voltage range], [GND_clamp], and
|* possibly the [POWER_clamp] keywords. If one or more of
|* [Rgnd], [Rpower], [Rac] and [Cac] keywords are used, then
|* the Model_type must be Terminator.
|*
|* BIRD2.2 addition
|* A "Terminator" is an input only device that can have analog loading effects
|* on the circuit being simulated but has no digital logic thresholds.
|* Examples of "Terminators" are: Capacitors, Termination Diodes, Pullup
|* resistors etc.
|*
|* BIRD7.2 addition
|* Model_types with "open_sink" specify that the output has
|* an OPEN side (the [Pullup] keyword is not used or I = 0mA
|* for all voltages specified) AND the output SINKS current.
|* Model_types with "open_drain" have the identical meaning and
|* are retained for backward compatibility. Model_types with
|* "open_source" specify that the output has an OPEN side (the
|* [Pulldown keyword is not used or I = 0mA for all voltages
|* specified) AND the output SOURCES current. Model_types with
|* "_ECL" specify that the model represents and ECL type logic
|* which follows different conventions for the [Pulldown] keyword.
|*
| Note that C_comp defines the silicon die capacitance. This |
| value should not include the capacitance of the package. |
| |
|------------------------------------------------------------------------------|
[Model] model_name
|*
|* BIRD7.2 and BIRD9.3 modification
Model_type Input, Output, I/O, 3-state, Open_drain, I/O_open_drain,
Open_sink, I/O_open_sink, Open_source, I/O_open_source,
Input_ECL, Output_ECL, I/O_ECL, Terminator | List one only
|*
Polarity Non-Inverting, Inverting | List one only, if any
Enable Active-High, Active-Low | List one only, if any
| Signals RAS, CAS, A(0-64), D(0-128),... | Local list, if desired
Vinl = 0.8V | input logic "low" DC voltage, if any
Vinh = 2.0V | input logic "high" DC voltage, if any
| variable typ min max
C_comp 12.0pF 10.0pF 15.0pF
|==============================================================================|
| Keyword: [Voltage range] |
| Required: Yes |
| Description: Used to define the power supply voltage tolerance over which |
| the model is intended to operate. |
| Usage Rules: Actual voltages (not percentages) are to be presented in the |
| usual typ, min, max format. "NA" is allowed for the min and |
| values only. |
| Other Notes: [Voltage range] also describes the voltage range over which |
| the various V/I curves and ramp rates were derived. |
|------------------------------------------------------------------------------|
| variable typ min max
[Voltage range] 5.0V 4.5V 5.5V
|******************************************************************************
|* BIRD3 replacement of [Voltage range] text above for VERSION 1.1X
|*==========================================================================
|* Keyword: [Voltage range]
|* Required: Yes, if [Pullup reference], [Pulldown reference],
|* [Power_clamp reference], and [GND_clamp reference] are not
|* present
|*Description: Used to define the power supply voltage tolerance over which
|* the the model is intended to operate. It also specifies the
|* default voltage rail the pullup and POWER_clamp V/I data is
|* referenced to.
|*Usage Rules: Actual voltages (not percentages) are to be presented in the
|* usual typ, min, max format. "NA" is allowed for the min and
|* max values only.
|*---------------------------------------------------------------------------
|* variable typ min max
[Voltage range] 5.0v 4.5v 5.5v
|*===========================================================================
|* Keyword: [Pullup reference]
|* Required: Yes, if the [Voltage range] keyword is not present.
|*Description: Used to define a voltage rail other than that defined by
|* the [Voltage range] keyword as the reference voltage
|* for the pullup V/I data.
|*Usage Rules: Actual voltages (not percentages) are to be presented in the
|* usual typ, min, max format. "NA" is allowed for the min and
|* max values only.
|*Other Notes: This keyword, if present, also defines the voltage range over
|* which the min and max dV/dt_r values are derived.
|*---------------------------------------------------------------------------
|* variable typ min max
[Pullup reference] 5.0V 4.5V 5.5V
|*===========================================================================
|* Keyword: [Pulldown reference]
|* Required: Yes, if the [Voltage range] keyword is not present.
|*Description: Used to define a power supply rail other than 0v as the
|* reference voltage for the pulldown V/I data. If this keyword
|* is not present the voltage data points in the pulldown V/I table
|* are referenced to 0v.
|*Usage Rules: Actual voltages (not percentages) are to be presented in the
|* usual typ, min, max format. "NA" is allowed for the min and
|* max values only.
|*Other Notes: This keyword, if present, also defines the voltage range over
|* which the min and max dV/dt_f values are derived.
|*---------------------------------------------------------------------------
|* variable typ min max
[Pulldown reference] 0V 0V 0V
|* Keyword: [POWER_clamp reference]
|* Required: Yes, if the [Voltage range] keyword is not present.
|*Description: Used to define a voltage rail other than that defined by
|* the [Voltage range] keyword as the reference voltage
|* for the POWER_clamp V/I data.
|*Usage Rules: Actual voltages (not percentages) are to be presented in the
|* usual typ, min, max format. "NA" is allowed for the min and
|* max values only.
|*Other Notes: Refer the "NOTES ON SPECIFYING POWER SUPPLIES" section below.
|*---------------------------------------------------------------------------
|* variable typ min max
[POWER_clamp reference] 5.0V 4.5V 5.5V
|*===========================================================================
|* Keyword: [GND_clamp reference]
|* Required: Yes, if the [Voltage range] keyword is not present.
|*Description: Used to define a power supply rail other than 0v as the
|* reference voltage for the GND_clamp V/I data. If this keyword
|* is not present the voltage data points in the GND_clamp V/I table
|* are referenced to 0v.
|*Usage Rules: Actual voltages (not percentages) are to be presented in the
|* usual typ, min, max format. "NA" is allowed for the min and
|* max values only.
|*Other Notes: Refer to the "NOTES ON SPECIFYING POWER SUPPLIES" section below.
|*---------------------------------------------------------------------------
|* variable typ min max
[GND_clamp reference] 0V 0V 0V
|*============================================================================
|* NOTES ON SPECIFYING POWER SUPPLIES
|* It is the intention that standard TTL and CMOS devices be specified
|* using only the [Voltage range] keyword. However, in cases where
|* the output characteristics of a device depend on more than a single
|* supply and ground, or a pullup, pulldown or clamp structure is referenced
|* to something other than the default supplys, the additional 'reference'
|* keywords are to be used.
|* If the [Voltage range] keyword is not present then all four of the
|* other keywords must be present. If the [Voltage range] keyword is
|* present the other keywords are optional and may or may not be used as
|* required. It is legal (although redundant) for an optional keyword to
|* specify the same voltage as specified by the [Voltage range] keyword.
|******************************************************************************
|==============================================================================|
| Keywords: [Pulldown], [Pullup], [GND_clamp], [POWER_clamp] |
| Required: Yes, if they exist in the device |
| Description: The data points under these keywords define the V/I curves of |
| the pulldown and pullup structures of an output buffer and the |
| V/I curves of the clamping diodes connected to the GND and the |
| POWER pins, respectively. |
|*
|* BIRD11.2 Continuation of Previous Paragraph:
|* Currents are considered positive
|* when their direction is into the component.
|*
| Usage Rules: In each of these sections the first column contains the |
| voltage value, and the three remaining columns hold the |
| typical, minimum, and maximum current values. The four |
| entries, Voltage, I(typ), I(min), and I(max) must be placed on |
| a single line and must be separated by at least one white |
| space or tab character. |
| All four columns are required under these keywords, however |
| data is only required in the typical column. If minimum |
| and/or maximum current values are not available, the reserved |
| word "NA" must be used. "NA" can be used for currents in the |
| typical column, but numeric values MUST be specified for the |
| first and last voltage points on any V/I curve. Each V/I |
| curve must have at least 2, but not more than 100, voltage |
| points. |
| Other Notes: It should be noted that the V/I curve of the [Pullup] and the |
| [POWER_clamp] structures are 'Vcc relative', meaning that the |
| voltage values are referenced to the Vcc pin. The voltages in |
| the data tables are derived from the equation: |
| Vtable = Vcc - Voutput |
| Therefore, for a 5V component, -5 V in the table actually |
| means 5 V above Vcc, which is +10 V with respect to ground; |
| and 10 V means 10 V below Vcc, which is -5 V with respect to |
| ground. Vcc-relative data is necessary to model a pullup |
| structure properly, since the output current of a pullup |
| structure depends on the voltage between the output and Vcc |
| pins and not the voltage between the output and ground pins. |
| Note that the [GND_clamp] V/I curve can include quiescent |
| input currents, or the currents of a 3-stated output if so |
| desired. |
|******************************************************************************
|* BIRD4 ADDITION FOR VERSION 1.1X
|* When tabulating data for ECL devices, the data in the pulldown table
|* is measured with the output in the 'logic low' state. In other words,
|* the data in the table represents the V-I characteristics of the
|* output when the output is at the most negative of its two logic
|* levels. Likewise, the data in the pullup table is measured with the
|* output in the 'logic one' state and represents the V-I characteristics
|* when the output is at the most positive logic level. Note that in BOTH
|* these cases the data is referenced to the VCC supply voltage, using
|* the equation Vtable = Vcc - Voutput.
|******************************************************************************
|------------------------------------------------------------------------------|
[Pulldown]
| Voltage I(typ) I(min) I(max)
|
-5.0V -40.0m -34.0m -45.0m
-4.0V -39.0m -33.0m -43.0m
| .
| .
0.0V 0.0m 0.0m 0.0m
| .
| .
5.0V 40.0m 34.0m 45.0m
10.0V 45.0m 40.0m 49.0m
|
[Pullup]
|
| Voltage I(typ) I(min) I(max)
|
-5.0V 32.0m 30.0m 35.0m
-4.0V 31.0m 29.0m 33.0m
| .
| .
0.0V 0.0m 0.0m 0.0m
| .
| .
5.0V -32.0m -30.0m -35.0m
10.0V -38.0m -35.0m -40.0m
|
[GND_clamp]
|
| Voltage I(typ) I(min) I(max)
|
-5.0V -3900.0m -3800.0m -4000.0m
-0.7V -80.0m -75.0m -85.0m
-0.6V -22.0m -20.0m -25.0m
-0.5V -2.4m -2.0m -2.9m
-0.4V 0.0m 0.0m 0.0m
5.0V 0.0m 0.0m 0.0m
|
[POWER_clamp]
|
| Voltage I(typ) I(min) I(max)
|
-5.0V 4450.0m NA NA
-0.7V 95.0m NA NA
-0.6V 23.0m NA NA
-0.5V 2.4m NA NA
-0.4V 0.0m NA NA
0.0V 0.0m NA NA
|*******************************************************************************
|* BIRD9.3 ADDITION FOR VERSION 1.1Y
|*==========================================================================
|* Keywords: [Rgnd], [Rpower], [Rac], [Cac]
|* Required: Yes, if they exist in the device
|* Description: The data for these keywords define the resistance values of
|* Rgnd and Rpower connected to GND and the POWER pins,
|* respectively.
|* Usage Rules: For each of these sections the three columns hold the
|* typical, minimum, and maximum resistance values. The three
|* entries for R(typ), R(min), and R(max) or C(typ), C(min),
|* and C(max) must be placed on a single line and must be
|* separated by at least one white space or tab character.
|* All three columns are required under these keywords, however
|* data is only required in the typical column. If minimum
|* and/or maximum values are not available, the reserved word
|* "NA" must be used indicating the R(typ) or C(typ) value by
|* default.
|* Other Notes: It should be noted that [Rpower] is connected to 'Vcc' and
|* [Rgnd] is connected to 'GND'. However, [GND_clamp reference]
|* voltages, if defined, apply to [Rgnd]. [POWER_clamp reference]
|* voltages, if defined, apply to [Rpower]. |* Either or both [Rgnd] and [Rpower] may be defined and may
|* co-exist with [GND_clamp] and [POWER_clamp] structures.
|* If an AC terminator is specified, then both [Rac] and [Cac]
|* are required.
|* When [Rgnd], [Rpower], or [Rac] and [Cac] are specified, the
|* Model_type must be Terminator.
|*------------------------------------------------------------------------------
|* variable R(typ) R(min) R(max)
|*
[Rgnd] 330Ohm 300Ohm 360Ohm | Parallel Terminator
[Rpower] 220Ohm 200Ohm NA |
|*
[Rac] 30Ohm NA NA |
|*
|* variable C(typ) C(min) C(max) | AC terminator
|*
[Cac] 50pF NA NA |
|*******************************************************************************
|==============================================================================|
| Keyword: [Ramp] |
| Required: Yes, except for inputs |
| Description: Used to define the rise and fall times of a buffer. |
| Sub-Params: dV/dt_r, dV/dt_f |
| Usage Rules: These parameters describe an ideal slope and can be expressed |
| as a ratio of any reasonable voltage and time values as shown |
| in the examples. The [Ramp] values are allowed to use "NA" |
| for the min and max values only. |
|------------------------------------------------------------------------------|
[Ramp]
| variable typ min max
dV/dt_r 4.2/1.8n 3.5/2.5n 5.0/1.1n
dV/dt_f 2.5/1.5n 2.0/2.3n 3.0/0.8n
|==============================================================================|
| Keyword: [End] |
| Required: Yes |
| Description: Used to define the end of the .ibs file. |
|------------------------------------------------------------------------------|
[End]
|==============================================================================|
| |
| NOTES ON DATA DERIVATION METHOD |
| |
| This section explains how data values are derived. The intention here is to |
| avoid over-guardbanding, enabling simulation results that are meaningful and |
| useful. This is accomplished by having each silicon vendor base their data |
| on typical process data, and then derate by voltage and temperature, and a |
| proprietary "X%" factor. This methodology also has the nice feature that |
| the data can be derived either from vendor-proprietary silicon models, or |
| typical device measurement over temperature/voltage. |
| |
| 1) V/I curves for CMOS devices: |
| typ = nominal voltage, 50 degrees C, typical process |
| min = low voltage tol, 100 degrees C, typical process, minus "X%" |
| max = hi voltage tol, 0 degrees C, typical process, plus "X%" |
| |
| V/I curves for bipolar devices: |
| typ = nominal voltage, 50 degrees C, typical process |
| min = low voltage tol, 0 degrees C, typical process, minus "X%" |
| max = hi voltage tol, 100 degrees C, typical process, plus "X%" |
| |
| where X% should be statistically determined by the silicon vendor |
| based on numerous fab lots, test chips, process controls, ... The |
| value of X need not be published in the IBIS file, and may decrease |
| over time as data on the I/O buffers and silicon process increases. |
| Temperatures are junction temperatures. |
| |
| 2) Voltage Ranges: |
Received on Fri May 6 11:00:06 1994
This archive was generated by hypermail 2.1.8 : Fri Jun 03 2011 - 09:52:28 PDT