ASICs...THE COURSE (1 WEEK)
1
SIMULATION
Key terms and concepts: Engineers used to prototype systems to check designs ?
Breadboarding is feasible for systems constructed from a few TTL parts ? It is impractical for an
ASIC ? Instead engineers turn to simulation
13.1 Types of Simulation
Key terms and concepts: simulation modes (high-level to low-level simulation–high-level is
more abstract, low-level more detailed): Behavioral simulation ? Functional simulation ? Static
timing analysis ? Gate-level simulation ? Switch-level simulation ? Transistor-level or circuit-level
simulation
13.2 The Comparator/MUX Example
Key terms and concepts: using input vectors to test or exercise a behavioral model ? simu-
lation can only prove a design does not work; it cannot prove that hardware will work
// comp_mux.v //1
module comp_mux(a, b, outp); input [2:0] a, b; output [2:0] outp; //2
function [2:0] compare; input [2:0] ina, inb; //3
begin if (ina <= inb) compare = ina; else compare = inb; end //4
endfunction //5
assign outp = compare(a, b); //6
endmodule //7
// testbench.v //1
module comp_mux_testbench; //2
integer i, j; //3
reg [2:0] x, y, smaller; wire [2:0] z; //4
always @(x) $display("t x y actual calculated"); //5
initial $monitor("%4g",$time,,x,,y,,z,,,,,,,smaller); //6
initial $dumpvars; initial #1000 $finish; //7
initial //8
13
2 SECTION 13 SIMULATION ASICS... THE COURSE
begin //9
for (i = 0; i <= 7; i = i + 1) //10
begin //11
for (j = 0; j <= 7; j = j + 1) //12
begin //13
x = i; y = j; smaller = (x <= y) ? x : y; //14
#1 if (z != smaller) $display("error"); //15
end //16
end //17
end //18
comp_mux v_1 (x, y, z); //19
endmodule //20
13.2.1 Structural Simulation
Key terms and concepts: logic synthesis produces a structural model from a behavioral model ?
reference model ? derived model ? vector-based simulation (or dynamic simulation)
`timescale 1ns / 10ps // comp_mux_o2.v //1
module comp_mux_o (a, b, outp); //2
input [2:0] a; input [2:0] b; //3
output [2:0] outp; //4
supply1 VDD; supply0 VSS; //5
mx21d1 b1_i1 (.i0(a[0]), .i1(b[0]), .s(b1_i6_zn), .z(outp[0])); //6
oa03d1 b1_i2 (.a1(b1_i9_zn), .a2(a[2]), .b1(a[0]), .b2(a[1]), //7
.c(b1_i4_zn), .zn(b1_i2_zn)); //8
nd02d0 b1_i3 (.a1(a[1]), .a2(a[0]), .zn(b1_i3_zn)); //9
nd02d0 b1_i4 (.a1(b[1]), .a2(b1_i3_zn), .zn(b1_i4_zn)); //10
mx21d1 b1_i5 (.i0(a[1]), .i1(b[1]), .s(b1_i6_zn), .z(outp[1])); //11
oa04d1 b1_i6 (.a1(b[2]), .a2(b1_i7_zn), .b(b1_i2_zn), //12
.zn(b1_i6_zn)); //13
in01d0 b1_i7 (.i(a[2]), .zn(b1_i7_zn)); //14
an02d1 b1_i8 (.a1(b[2]), .a2(a[2]), .z(outp[2])); //15
in01d0 b1_i9 (.i(b[2]), .zn(b1_i9_zn)); //16
endmodule //17
`timescale 1 ns / 10 ps //1
module mx21d1 (z, i0, i1, s); input i0, i1, s; output z; //2
not G3(N3, s); //3
and G4(N4, i0, N3), G5(N5, s, i1), G6(N6, i0, i1); //4
or G7(z, N4, N5, N6); //5
specify //6
(i0*>z) = (0.279:0.504:0.900, 0.276:0.498:0.890); //7
ASICs... THE COURSE 13.2 The Comparator/MUX Example 3
(i1*>z) = (0.248:0.448:0.800, 0.264:0.476:0.850); //8
(s*>z) = (0.285:0.515:0.920, 0.298:0.538:0.960); //9
endspecify //10
endmodule //11
`timescale 1 ps / 1 ps // comp_mux_testbench2.v //1
module comp_mux_testbench2; //2
integer i, j; integer error; //3
reg [2:0] x, y, smaller; wire [2:0] z, ref; //4
always @(x) $display("t x y derived reference"); //5
// initial $monitor("%8.2f",$time/1e3,,x,,y,,z,,,,,,,,ref); //6
initial $dumpvars; //7
initial begin //8
error = 0; #1e6 $display("%4g", error, " errors"); //9
$finish; //10
end //11
initial begin //12
for (i = 0; i <= 7; i = i + 1) begin //13
for (j = 0; j <= 7; j = j + 1) begin //14
x = i; y = j; #10e3; //15
$display("%8.2f",$time/1e3,,x,,y,,z,,,,,,,,ref); //16
if (z != ref) //17
begin $display("error"); error = error + 1; end //18
end //19
end //20
end //21
comp_mux_o v_1 (x, y, z); // comp_mux_o2.v //22
reference v_2 (x, y, ref); //23
endmodule //24
// reference.v //1
module reference(a, b, outp); //2
input [2:0] a, b;output [2:0] outp; //3
assign outp = (a <= b) ? a : b; // different from comp_mux //4
endmodule //5
13.2.2 Static Timing Analysis
Key terms and concepts: “What is the longest delay in my circuit?” ? timing analysis finds the
critical path and its delay ? timing analysis does not find the input vectors that activate the critical
path ? Boolean relations ? false paths ? a timing-analyzer is more logic calculator than logic
simulator
4 SECTION 13 SIMULATION ASICS... THE COURSE
13.2.3 Gate-Level Simulation
Key terms and concepts: differences between functional simulation, timing analysis, and gate-
level simulation
# The calibration was done at Vdd=4.65V, Vss=0.1V, T=70 degrees C
Time = 0:0 [0 ns]
a = 'D6 [0] (input)(display)
b = 'D7 [0] (input)(display)
outp = 'Buuu ('Du) [0] (display)
outp --> 'B1uu ('Du) [.47]
outp --> 'B11u ('Du) [.97]
outp --> 'D6 [4.08]
a --> 'D7 [10]
b --> 'D6 [10]
outp --> 'D7 [10.97]
outp --> 'D6 [14.15]
Time = 0:0 +20ns [20 ns]
13.2.4 Net Capacitance
Key terms and concepts: net capacitance (interconnect capacitance or wire capacitance) ?
wire-load model, wire-delay model, or interconnect model
@nodes
a R10 W1; a[2] a[1] a[0]
b R10 W1; b[2] b[1] b[0]
outp R10 W1; outp[2] outp[1] outp[0]
@data
.00 a -> 'D6
.00 b -> 'D7
.00 outp -> 'Du
.53 outp -> 'Du
.93 outp -> 'Du
4.42 outp -> 'D6
10.00 a -> 'D7
10.00 b -> 'D6
11.03 outp -> 'D7
14.43 outp -> 'D6
### END OF SIMULATION TIME = 20 ns
@end
ASICs... THE COURSE 13.3 Logic Systems 5
13.3 Logic Systems
Key terms and concepts: Digital simulation ? logic values (or logic states) from a logic
system ? A two-value logic system (or two-state logic system) has logic value '0' ( logic level
'zero' ) and a logic value '1' (logic level 'one') ? logic value 'X' (unknown logic level) or
unknown ? an unknown can propagate through a circuit ? to model a three-state bus, we need
a high-impedance state (logic level of 'zero' or 'one') but it is not being driven ? A four-value
logic system
13.3.1 Signal Resolution
Key terms and concepts: signal-resolution function ? commutative and associative
13.3.2 Logic Strength
Key terms and concepts: n-channel transistors produce a logic level 'zero' (with a forcing
strength) ? p-channel transistors force a logic level 'one' ? An n-channel transistor provides a
A four-value logic system
Logic state Logic level Logic value
0 zero zero
1 one one
X zero or one unknown
Z zero, one, or neither high impedance
A resolution function R{A, B} that predicts the result of two drivers simultaneously
attempting to drive signals with values A and B onto a bus
R{A, B} B=0 B=1 B=X B=Z
A=0 0 X X 0
A=1 X 1 X 1
A=X X X X X
A=Z 0 1 X Z
6 SECTION 13 SIMULATION ASICS... THE COURSE
weak logic level 'one', a resistive 'one', with resistive strength ? high impedance ? Verilog
logic system ? VHDL signal resolution using VHDL signal-resolution functions
function "and"(l,r : std_ulogic_vector) return std_ulogic_vector
is --1
alias lv : std_ulogic_vector (1 to l'LENGTH ) is l; --2
alias rv : std_ulogic_vector (1 to r'LENGTH ) is r; --3
variable result : std_ulogic_vector (1 to l'LENGTH ); --4
A 12-state logic system
Logic level
Logic strength zero unknown one
strong S0 SX S1
weak W0 WX W1
high impedance Z0 ZX Z1
unknown U0 UX U1
Verilog logic strengths
Logic strength Strength number Models Abbreviation
supply drive 7 power supply supply Su
strong drive 6 default gate and assign output strength strong St
pull drive 5 gate and assign output strength pull Pu
large capacitor 4 size of trireg net capacitor large La
weak drive 3 gate and assign output strength weak We
medium capacitor 2 size of trireg net capacitor medium Me
small capacitor 1 size of trireg net capacitor small Sm
high impedance 0 not applicable highz Hi
The nine-value logic system, IEEE Std 1164-1993.
Logic state Logic value Logic state Logic value
'0' strong low 'X' strong unknown
'1' strong high 'W' weak unknown
'L' weak low 'Z' high impedance
'H' weak high '-' don’t care
'U' uninitialized
ASICs... THE COURSE 13.4 How Logic Simulation Works 7
constant and_table : stdlogic_table := ( --5
----------------------------------------------------------- --6
--| U X 0 1 Z W L H - | | --7
----------------------------------------------------------- --8
( 'U', 'U', '0', 'U', 'U', 'U', '0', 'U', 'U' ), -- | U | --9
( 'U', 'X', '0', 'X', 'X', 'X', '0', 'X', 'X' ), -- | X | --10
( '0', '0', '0', '0', '0', '0', '0', 'U', '0' ), -- | 0 | --11
( 'U', 'X', '0', '1', 'X', 'X', '0', '1', 'X' ), -- | 1 | --12
( 'U', 'X', '0', 'X', 'X', 'X', '0', 'X', 'X' ), -- | Z | --13
( 'U', 'X', '0', 'X', 'X', 'X', '0', 'X', 'X' ), -- | W | --14
( '0', '0', '0', '0', '0', '0', '0', '0', '0' ), -- | L | --15
( 'U', 'X', '0', '1', 'X', 'X', '0', '1', 'X' ), -- | H | --16
( 'U', 'X', '0', 'X', 'X', 'X', '0', 'X', 'X' ), -- | - |); --17
begin --18
if (l'LENGTH /= r'LENGTH) then assert false report --19
"arguments of overloaded 'and' operator are not of the same --20
length" --21
severity failure; --22
else --23
for i in result'RANGE loop --24
result(i) := and_table ( lv(i), rv(i) ); --25
end loop; --26
end if; --27
return result; --28
end "and"; --29
13.4 How Logic Simulation Works
Key terms and concepts: event-driven simulator ? event ? event queue or event list ? evaluation ?
time step ? interpreted-code simulator ? compiled-code simulator ? native-code simulator ?
evaluation list ? simulation cycle, or an event–evaluation cycle ? time wheel
model nd01d1 (a, b, zn)
function (a, b) !(a & b); function end
model end
nand nd01d1(a2, b3, r7)
8 SECTION 13 SIMULATION ASICS... THE COURSE
struct Event {
event_ptr fwd_link, back_link; /* event list */
event_ptr node_link; /* list of node events */
node_ptr event_node; /* node for the event */
node_ptr cause; /* node causing event */
port_ptr port; /* port which caused this event */
long event_time; /* event time, in units of delta */
char new_value; /* new value: '1' '0' etc. */
};
13.4.1 VHDL Simulation Cycle
Key terms and concepts: simulation cycle ? elaboration ? a delta cycle takes delta time? time
step? postponed processes
A VHDL simulation cycle consists of the following steps:
1. The current time, tc is set equal to tn.
2. Each active signal in the model is updated and events may occur as a result.
3. For each process P, if P is currently sensitive to a signal S, and an event has occurred on
signal S in this simulation cycle, then process P resumes.
4. Each resumed process is executed until it suspends.
5. The time of the next simulation cycle, tn, is set to the earliest of:
a. the next time at which a driver becomes active or
b. the next time at which a process resumes
6. If tn = tc, then the next simulation cycle is a delta cycle.
7. Simulation is complete when we run out of time (tn =TIME'HIGH) and there are no active
drivers or process resumptions at tn
13.4.2 Delay
Key terms and concepts: delay mechanism ? transport delay is characteristic of wires and
transmission lines ? Inertial delay models the behavior of logic cells ? a logic cell will not transmit
a pulse that is shorter than the switching time of the circuit, the default pulse-rejection limit
Op <= Ip after 10 ns; --1
Op <= inertial Ip after 10 ns; --2
Op <= reject 10 ns inertial Ip after 10 ns; --3
-- Assignments using transport delay: --1
Op <= transport Ip after 10 ns; --2
Op <= transport Ip after 10 ns, not Ip after 20 ns; --3
ASICs... THE COURSE 13.5 Cell Models 9
-- Their equivalent assignments: --4
Op <= reject 0 ns inertial Ip after 10 ns; --5
Op <= reject 0 ns inertial Ip after 10 ns, not Ip after 10 ns; --6
13.5 Cell Models
Key terms and concepts: delay model ? power model ? timing model ? primitive model
There are several different kinds of logic cell models:
? Primitive models, produced by the ASIC library company and describe the function and
properties of logic cells using primitive functions.
? Verilog and VHDL models produced by an ASIC library company from the primitive
models.
? Proprietary models produced by library companies that describe small logic cells or
functions such as microprocessors.
13.5.1 Primitive Models
Key terms and concepts: primitive model ? a designer does not normally see a primitive model;
it may only be used by an ASIC library company to generate other models
Function
(timingModel = oneOf("ism","pr"); powerModel = oneOf("pin"); )
Rec
Logic = Function (A1; A2; )Rec ZN = not (A1 AND A2); End; End;
miscInfo = Rec Title = "2-Input NAND, 1X Drive"; freq_fact = 0.5;
tml = "nd02d1 nand 2 * zn a1 a2";
MaxParallel = 1; Transistors = 4; power = 0.179018;
Width = 4.2; Height = 12.6; productName = "stdcell35"; libraryName =
"cb35sc"; End;
Pin = Rec
A1 = Rec input; cap = 0.010; doc = "Data Input"; End;
A2 = Rec input; cap = 0.010; doc = "Data Input"; End;
ZN = Rec output; cap = 0.009; doc = "Data Output"; End; End;
Symbol = Select
timingModel
On pr Do Rec
tA1D_fr = |( Rec prop = 0.078; ramp = 2.749; End);
tA1D_rf = |( Rec prop = 0.047; ramp = 2.506; End);
tA2D_fr = |( Rec prop = 0.063; ramp = 2.750; End);
tA2D_rf = |( Rec prop = 0.052; ramp = 2.507; End); End
On ism Do Rec
10 SECTION 13 SIMULATION ASICS... THE COURSE
tA1D_fr = |( Rec A0 = 0.0015; dA = 0.0789; D0 = -0.2828;
dD = 4.6642; B = 0.6879; Z = 0.5630; End );
tA1D_rf = |( Rec A0 = 0.0185; dA = 0.0477; D0 = -0.1380;
dD = 4.0678; B = 0.5329; Z = 0.3785; End );
tA2D_fr = |( Rec A0 = 0.0079; dA = 0.0462; D0 = -0.2819;
dD = 4.6646; B = 0.6856; Z = 0.5282; End );
tA2D_rf = |( Rec A0 = 0.0060; dA = 0.0464; D0 = -0.1408;
dD = 4.0731; B = 0.6152; Z = 0.4064; End ); End; End;
Delay = |( Rec from = pin.A1; to = pin.ZN;
edges = Rec fr = Symbol.tA1D_fr; rf = Symbol.tA1D_rf; End; End, Rec
from = pin.A2; to = pin.ZN; edges = Rec fr = Symbol.tA2D_fr; rf =
Symbol.tA2D_rf; End; End );
MaxRampTime = |( Rec check = pin.A1; riseTime = 3.000; fallTime =
3.000; End, Rec check = pin.A2; riseTime = 3.000; fallTime =
3.000; End, Rec check = pin.ZN; riseTime = 3.000; fallTime =
3.000; End );
DynamicPower = |( Rec rise = { ZN }; val = 0.003; End); End; End
13.5.2 Synopsys Models
Key terms and concepts: vendor models ? each logic cell is part of a file that also contains wire-
load models and other characterization information for the cell library ? not all of the information
from a primitive model is present in a vendor model
cell (nd02d1) {
/* title : 2-Input NAND, 1X Drive */
/* pmd checksum : 'HBA7EB26C */
area : 1;
pin(a1) { direction : input; capacitance : 0.088;
fanout_load : 0.088; }
pin(a2) { direction : input; capacitance : 0.087;
fanout_load : 0.087; }
pin(zn) { direction : output; max_fanout : 1.786;
max_transition : 3; function : "(a1 a2)'";
timing() {
timing_sense : "negative_unate"
intrinsic_rise : 0.24 intrinsic_fall : 0.17
rise_resistance : 1.68 fall_resistance : 1.13
related_pin : "a1" }
timing() { timing_sense : "negative_unate"
intrinsic_rise : 0.32 intrinsic_fall : 0.18
rise_resistance : 1.68 fall_resistance : 1.13
ASICs... THE COURSE 13.5 Cell Models 11
related_pin : "a2"
} } } /* end of cell */
13.5.3 Verilog Models
Key terms and concepts: Verilog timing models ? SDF file contains back-annotation timing
delays ? delays are calculated by a delay calculator ? $sdf_annotate performs back-
annotation ? golden simulator
`celldefine //1
`delay_mode_path //2
`suppress_faults //3
`enable_portfaults //4
`timescale 1 ns / 1 ps //5
module in01d1 (zn, i); input i; output zn; not G2(zn, i); //6
specify specparam //7
InCap$i = 0.060, OutCap$zn = 0.038, MaxLoad$zn = 1.538, //8
R_Ramp$i$zn = 0.542:0.980:1.750, F_Ramp$i$zn = 0.605:1.092:1.950; //9
specparam cell_count = 1.000000; specparam Transistors = 4 ; //10
specparam Power = 1.400000; specparam MaxLoadedRamp = 3 ; //11
(i => zn) = (0.031:0.056:0.100, 0.028:0.050:0.090); //12
endspecify //13
endmodule //14
`nosuppress_faults //15
`disable_portfaults //16
`endcelldefine //17
`timescale 1 ns / 1 ps //1
module SDF_b; reg A; in01d1 i1 (B, A); //2
initial begin A = 0; #5; A = 1; #5; A = 0; end //3
initial $monitor("T=%6g",$realtime," A=",A," B=",B); //4
endmodule //5
T= 0 A=0 B=x
T= 0.056 A=0 B=1
T= 5 A=1 B=1
T= 5.05 A=1 B=0
T= 10 A=0 B=0
T=10.056 A=0 B=1
12 SECTION 13 SIMULATION ASICS... THE COURSE
(DELAYFILE
(SDFVERSION "3.0") (DESIGN "SDF.v") (DATE "Aug-13-96")
(VENDOR "MJSS") (PROGRAM "MJSS") (VERSION "v0")
(DIVIDER .) (TIMESCALE 1 ns)
(CELL (CELLTYPE "in01d1")
(INSTANCE SDF_b.i1)
(DELAY (ABSOLUTE
(IOPATH i zn (1.151:1.151:1.151) (1.363:1.363:1.363))
))
)
)
`timescale 1 ns / 1 ps //1
module SDF_b; reg A; in01d1 i1 (B, A); //2
initial begin //3
$sdf_annotate ( "SDF_b.sdf", SDF_b, , "sdf_b.log", "minimum", , ); //4
A = 0; #5; A = 1; #5; A = 0; end //5
initial $monitor("T=%6g",$realtime," A=",A," B=",B); //6
endmodule //7
Here is the output (from MTI V-System/Plus) including back-annotated timing:
T= 0 A=0 B=x
T= 1.151 A=0 B=1
T= 5 A=1 B=1
T= 6.363 A=1 B=0
T= 10 A=0 B=0
T=11.151 A=0 B=1
13.5.4 VHDL Models
Key terms and concepts: VHDL alone does not offer a standard way to perform back-annotation.
? VITAL
library IEEE; use IEEE.STD_LOGIC_1164.all;
library COMPASS_LIB; use COMPASS_LIB.COMPASS_ETC.all;
entity bknot is
generic (derating : REAL := 1.0; Z1_cap : REAL := 0.000;
INSTANCE_NAME : STRING := "bknot");
port (Z2 : in Std_Logic; Z1 : out STD_LOGIC);
end bknot;
ASICs... THE COURSE 13.5 Cell Models 13
architecture bknot of bknot is
constant tplh_Z2_Z1 : TIME := (1.00 ns + (0.01 ns * Z1_Cap)) *
derating;
constant tphl_Z2_Z1 : TIME := (1.00 ns + (0.01 ns * Z1_Cap)) *
derating;
begin
process(Z2)
variable int_Z1 : Std_Logic := 'U';
variable tplh_Z1, tphl_Z1, Z1_delay : time := 0 ns;
variable CHANGED : BOOLEAN;
begin
int_Z1 := not (Z2);
if Z2'EVENT then
tplh_Z1 := tplh_Z2_Z1; tphl_Z1 := tphl_Z2_Z1;
end if;
Z1_delay := F_Delay(int_Z1, tplh_Z1, tphl_Z1);
Z1 <= int_Z1 after Z1_delay;
end process;
end bknot;
configuration bknot_CON of bknot is for bknot end for;
end bknot_CON;
13.5.5 VITAL Models
Key terms and concepts: VITAL ? VHDL Initiative Toward ASIC Libraries, IEEE Std 1076.4
[1995] ? . sign-off quality ASIC libraries using an approved cell library and a golden simulator
library IEEE; use IEEE.STD_LOGIC_1164.all; --1
use IEEE.VITAL_timing.all; use IEEE.VITAL_primitives.all; --2
entity IN01D1 is --3
generic ( --4
tipd_I : VitalDelayType01 := (0 ns, 0 ns); --5
tpd_I_ZN : VitalDelayType01 := (0 ns, 0 ns) ); --6
port ( --7
I : in STD_LOGIC := 'U'; --8
ZN : out STD_LOGIC := 'U' ); --9
attribute VITAL_LEVEL0 of IN01D1 : entity is TRUE; --10
end IN01D1; --11
architecture IN01D1 of IN01D1 is --12
attribute VITAL_LEVEL1 of IN01D1 : architecture is TRUE; --13
signal I_ipd : STD_LOGIC := 'X'; --14
begin --15
WIREDELAY:block --16
begin VitalWireDelay(I_ipd, I, tipd_I); end block; --17
14 SECTION 13 SIMULATION ASICS... THE COURSE
VITALbehavior : process (I_ipd) --18
variable ZN_zd : STD_LOGIC; --19
variable ZN_GlitchData : VitalGlitchDataType; --20
begin --21
ZN_zd := VitalINV(I_ipd); --22
VitalPathDelay01( --23
OutSignal => ZN, --24
OutSignalName => "ZN", --25
OutTemp => ZN_zd, --26
Paths => (0 => (I_ipd'LAST_EVENT, tpd_I_ZN, TRUE)), --27
GlitchData => ZN_GlitchData, --28
DefaultDelay => VitalZeroDelay01, --29
Mode => OnEvent, --30
MsgOn => FALSE, --31
XOn => TRUE, --32
MsgSeverity => ERROR); --33
end process; --34
end IN01D1; --35
library IEEE; use IEEE.STD_LOGIC_1164.all; --1
entity SDF is port ( A : in STD_LOGIC; B : out STD_LOGIC ); --2
end SDF; --3
architecture SDF of SDF is --4
component in01d1 port ( I : in STD_LOGIC; ZN : out STD_LOGIC ); --5
end component; --6
begin i1: in01d1 port map ( I => A, ZN => B); --7
end SDF; --8
library STD; use STD.TEXTIO.all; --1
library IEEE; use IEEE.STD_LOGIC_1164.all; --2
entity SDF_testbench is end SDF_testbench; --3
architecture SDF_testbench of SDF_testbench is --4
component SDF port ( A : in STD_LOGIC; B : out STD_LOGIC ); --5
end component; --6
signal A, B : STD_LOGIC := '0'; --7
begin --8
SDF_b : SDF port map ( A => A, B => B); --9
process begin --10
A <= '0'; wait for 5 ns; A <= '1'; --11
wait for 5 ns; A <= '0'; wait; --12
end process; --13
process (A, B) variable L: LINE; begin --14
write(L, now, right, 10, TIME'(ps)); --15
write(L, STRING'(" A=")); write(L, TO_BIT(A)); --16
write(L, STRING'(" B=")); write(L, TO_BIT(B)); --17
writeline(output, L); --18
ASICs... THE COURSE 13.5 Cell Models 15
end process; --19
end SDF_testbench; --20
(DELAYFILE
(SDFVERSION "3.0") (DESIGN "SDF.vhd") (DATE "Aug-13-96")
(VENDOR "MJSS") (PROGRAM "MJSS") (VERSION "v0")
(DIVIDER .) (TIMESCALE 1 ns)
(CELL (CELLTYPE "in01d1")
(INSTANCE i1)
(DELAY (ABSOLUTE
(IOPATH i zn (1.151:1.151:1.151) (1.363:1.363:1.363))
(PORT i (0.021:0.021:0.021) (0.025:0.025:0.025))
))
)
)
<msmith/MTI/vital> vsim -c -sdfmax /sdf_b=SDF_b.sdf sdf_testbench
...
# 0 ps A=0 B=0
# 0 ps A=0 B=0
# 1176 ps A=0 B=1
# 5000 ps A=1 B=1
# 6384 ps A=1 B=0
# 10000 ps A=0 B=0
# 11176 ps A=0 B=1
13.5.6 SDF in Simulation
Key terms and concepts: SDF is also used to describe forward-annotation of timing constraints
from logic synthesis
(DELAYFILE
(SDFVERSION "1.0")
(DESIGN "halfgate_ASIC_u")
(DATE "Aug-13-96")
(VENDOR "Compass")
(PROGRAM "HDL Asst")
(VERSION "v9r1.2")
(DIVIDER .)
(TIMESCALE 1 ns)
16 SECTION 13 SIMULATION ASICS... THE COURSE
(CELL (CELLTYPE "in01d0")
(INSTANCE v_1.B1_i1)
(DELAY (ABSOLUTE
(IOPATH I ZN (1.151:1.151:1.151) (1.363:1.363:1.363))
))
)
(CELL (CELLTYPE "pc5o06")
(INSTANCE u1_2)
(DELAY (ABSOLUTE
(IOPATH I PAD (1.216:1.216:1.216) (1.249:1.249:1.249))
))
)
(CELL (CELLTYPE "pc5d01r")
(INSTANCE u0_2)
(DELAY (ABSOLUTE
(IOPATH PAD CIN (.169:.169:.169) (.199:.199:.199))
))
)
)
(DELAYFILE
...
(PROCESS "FAST-FAST")
(TEMPERATURE 0:55:100)
(TIMESCALE 100ps)
(CELL (CELLTYPE "CHIP")
(INSTANCE TOP)
(DELAY (ABSOLUTE
(INTERCONNECT A.INV8.OUT B.DFF1.Q (:0.6:) (:0.6:))
)))
(INSTANCE B.DFF1)
(DELAY (ABSOLUTE
(IOPATH (POSEDGE CLK) Q (12:14:15) (11:13:15))))
(DELAYFILE
(DESIGN "MYDESIGN")
(DATE "26 AUG 1996")
(VENDOR "ASICS_INC")
(PROGRAM "SDF_GEN")
(VERSION "3.0")
(DIVIDER .)
ASICs... THE COURSE 13.6 Delay Models 17
(VOLTAGE 3.6:3.3:3.0)
(PROCESS "-3.0:0.0:3.0")
(TEMPERATURE 0.0:25.0:115.0)
(TIMESCALE )
(CELL
(CELLTYPE "AOI221")
(INSTANCE X0)
(DELAY (ABSOLUTE
(IOPATH A1 Y (1.11:1.42:2.47) (1.39:1.78:3.19))
(IOPATH A2 Y (0.97:1.30:2.34) (1.53:1.94:3.50))
(IOPATH B1 Y (1.26:1.59:2.72) (1.52:2.01:3.79))
(IOPATH B2 Y (1.10:1.45:2.56) (1.66:2.18:4.10))
(IOPATH C1 Y (0.79:1.04:1.91) (1.36:1.62:2.61))
))))
13.6 Delay Models
Key terms and concepts: timing model describes delays outside logic cells ? delay model
describes delays inside logic cells ? pin-to-pin delay is a delay between an input pin and an
output pin of a logic cell ? pin delay is a delay lumped to a certain pin of a logic cell (usually an
input) ? net delay or wire delay is a delay outside a logic cell ? prop–ramp delay model
specify specparam //1
InCap$i = 0.060, OutCap$zn = 0.038, MaxLoad$zn = 1.538, //2
R_Ramp$i$zn = 0.542:0.980:1.750, F_Ramp$i$zn = 0.605:1.092:1.950; //3
specparam cell_count = 1.000000; specparam Transistors = 4 ; //4
specparam Power = 1.400000; specparam MaxLoadedRamp = 3 ; //5
(i=>zn)=(0.031:0.056:0.100, 0.028:0.050:0.090); //6
13.6.1 Using a Library Data Book
Key terms and concepts: area-optimized library (small) ? performance-optimized library
(fast)
Input capacitances for an inverter family (pF)
Library inv1 invh invs inv8 inv12
Area 0.034 0.067 0.133 0.265 0.397
Performance 0.145 0.292 0.584 1.169 1.753
18 SECTION 13 SIMULATION ASICS... THE COURSE
Delay information for a 2:1 MUX
Propagation delay
Area Performance
From input To output Extrinsic/nspF –1 Intrinsic /ns Extrinsic /ns Intrinsic /ns
D0\ Z\ 2.10 1.42 0.5 0.8
D0/ Z/ 3.66 1.23 0.68 0.70
D1\ Z\ 2.10 1.42 0.50 0.80
D1/ Z/ 3.66 1.23 0.68 0.70
SD\ Z\ 2.10 1.42 0.50 0.80
SD\ Z/ 3.66 1.09 0.70 0.73
SD/ Z\ 2.10 2.09 0.5 1.09
SD/ Z/ 3.66 1.23 0.68 0.70
Process derating factors Temperature and voltage derating factors
Process Derating fac-tor Supply voltage
Slow 1.31 Tempera-ture/°C 4.5V 4.75V 5.00V 5.25V 5.50V
Nominal 1.0 –40 0.77 0.73 0.68 0.64 0.61
Fast 0.75 0 1.00 0.93 0.87 0.82 0.78
25 1.14 1.07 1.00 0.94 0.90
85 1.50 1.40 1.33 1.26 1.20
100 1.60 1.49 1.41 1.34 1.28
125 1.76 1.65 1.56 1.47 1.41
ASICs... THE COURSE 13.6 Delay Models 19
13.6.2 Input-Slope Delay Model
Key terms and concepts: submicron technologies must account for the effects of the rise (and
fall) time of the input waveforms to a logic cell ? nonlinear delay model
The input-slope model predicts delay in the fast-ramp region, DISM (50 %, FR), as follows
(0.5 trip points):
13.6.3 Limitations of Logic Simulation
Key terms and concepts: pin-to-pin delay model ? timing information for most gate-level
simulators is calculated once, before simulation ? state-dependent timing
DISM (50%, FR)
= A0 + D0CL + 0.5OR = A0 + D0CL + dA /2 + dDCL/2
= 0.0015 + 0.5 × 0.0789 + (–0.2828 + 0.5 × 4.6642) CL
= 0.041 + 2.05CL
Switching characteristics of a two-input NAND gate
Fanout
Symbol Parameter FO = 0/ns FO = 1/ns FO = 2/ns FO = 4/ns FO = 8/ns K/nspF–1
tPLH Propagation delay, A to X 0.25 0.35 0.45 0.65 1.05 1.25
tPHL Propagation delay, B to X 0.17 0.24 0.30 0.42 0.68 0.79
tr Output rise time, X 1.01 1.28 1.56 2.10 3.19 3.40
tf Output fall time, X 0.54 0.69 0.84 1.13 1.71 1.83
20 SECTION 13 SIMULATION ASICS... THE COURSE
13.7 Static Timing Analysis
Key terms and concepts: static timing analysis ? pipelining ? critical path
Instance name in pin-->out pin tr total incr cell
--------------------------------------------------------------------
END_OF_PATH
outp_2_ R 27.26
OUT1 : D--->PAD R 27.26 7.55 OUTBUF
I_1_CM8 : S11--->Y R 19.71 4.40 CM8
I_2_CM8 : S11--->Y R 15.31 5.20 CM8
I_3_CM8 : S11--->Y R 10.11 4.80 CM8
IN1 : PAD--->Y R 5.32 5.32 INBUF
a_2_ R 0.00 0.00
BEGIN_OF_PATH
// comp_mux_rrr.v //1
module comp_mux_rrr(a, b, clock, outp); //2
input [2:0] a, b; output [2:0] outp; input clock; //3
reg [2:0] a_r, a_rr, b_r, b_rr, outp; reg sel_r; //4
wire sel = ( a_r <= b_r ) ? 0 : 1; //5
always @ (posedge clock) begin a_r <= a; b_r <= b; end //6
always @ (posedge clock) begin a_rr <= a_r; b_rr <= b_r; end //7
always @ (posedge clock) outp <= sel_r ? b_rr : a_rr; //8
always @ (posedge clock) sel_r <= sel; //9
endmodule //10
---------------------INPAD to SETUP longest path---------------------
Rise delay, Worst case
Instance name in pin-->out pin tr total incr cell
--------------------------------------------------------------------
Switching characteristics of a half adder
Fanout
Symbol Parameter FO = 0/ns FO = 1/ns FO = 2/ns FO = 4/ns FO = 8/ns K/nspF –1
tPLH Delay, A to S (B = '0') 0.58 0.68 0.78 0.98 1.38 1.25
tPHL Delay, A to S (B = '1') 0.93 0.97 1.00 1.08 1.24 0.48
tPLH Delay, B to S (B = '0') 0.89 0.99 1.09 1.29 1.69 1.25
tPHL Delay, B to S (B = '1') 1.00 1.04 1.08 1.15 1.31 0.48
tPLH Delay, A to CO 0.43 0.53 0.63 0.83 1.23 1.25
tPHL Delay, A to CO 0.59 0.63 0.67 0.75 0.90 0.48
tr Output rise time, X 1.01 1.28 1.56 2.10 3.19 3.40
tf Output fall time, X 0.54 0.69 0.84 1.13 1.71 1.83
ASICs... THE COURSE 13.7 Static Timing Analysis 21
END_OF_PATH
D.a_r_ff_b2 R 4.52 0.00 DF1
INBUF_24 : PAD--->Y R 4.52 4.52 INBUF
a_2_ R 0.00 0.00
BEGIN_OF_PATH
---------------------CLOCK to SETUP longest path---------------------
Rise delay, Worst case
Instance name in pin-->out pin tr total incr cell
--------------------------------------------------------------------
END_OF_PATH
D.sel_r_ff R 9.99 0.00 DF1
I_1_CM8 : S10--->Y R 9.99 0.00 CM8
I_3_CM8 : S00--->Y R 9.99 4.40 CM8
a_r_ff_b1 : CLK--->Q R 5.60 5.60 DF1
BEGIN_OF_PATH
---------------------CLOCK to OUTPAD longest path--------------------
Rise delay, Worst case
Instance name in pin-->out pin tr total incr cell
--------------------------------------------------------------------
END_OF_PATH
outp_2_ R 11.95
OUTBUF_31 : D--->PAD R 11.95 7.55 OUTBUF
outp_ff_b2 : CLK--->Q R 4.40 4.40 DF1
BEGIN_OF_PATH
A timing analyzer examines the following types of paths:
1. An entry path (or input-to-D path) to a pipelined design. The longest entry delay (or input-
to-setup delay) is 4.52 ns.
2. A stage path (register-to-register path or clock-to-D path) in a pipeline stage. The longest
stage delay (clock-to-D delay) is 9.99 ns.
3. An exit path (clock-to-output path) from the pipeline. The longest exit delay (clock-to-out-
put delay) is 11.95 ns.
13.7.1 Hold Time
Key terms and concepts: Hold-time problems occur if there is clock skew between adjacent flip-
flops ? To check for hold-time violations we find the clock skew for each clock-to-D path
timer> shortest
1st shortest path to all endpins
Rank Total Start pin First Net End Net End pin
0 4.0 b_rr_ff_b1:CLK b_rr_1_ DEF_NET_48 outp_ff_b1:D
1 4.1 a_rr_ff_b2:CLK a_rr_2_ DEF_NET_46 outp_ff_b2:D
... 8 similar lines omitted ...
22 SECTION 13 SIMULATION ASICS... THE COURSE
13.7.2 Entry Delay
Key terms and concepts: Before we can measure clock skew, we need to analyze the entry
delays, including the clock tree
13.7.3 Exit Delay
Key terms and concepts: exit delays (the longest path between clock-pad input and an output) ?
critical path and operating frequency
13.7.4 External Setup Time
Key terms and concepts: external set-up time ? internal set-up time ? clock delay
Each of the six chip data inputs must satisfy the following set-up equation:
13.8 Formal Verification
Key terms and concepts: logic synthesis converts a behavioral model to a structural model ? How
do we know that the two are the same? ? formal verification can prove they are equivalent
13.8.1 An Example
Key terms and concepts: reference model ? derived model ? (1) the HDL is parsed ? (2) a
finite-state machine compiler extracts the states ? (3) a proof generator automatically
generates formulas to be proved ? (4) the theorem prover attempts to prove the formulas
entity Alarm is --1
port(Clock, Key, Trip : in bit; Ring : out bit); --2
end Alarm; --3
architecture RTL of Alarm is --1
type States is (Armed, Off, Ringing); signal State : States; --2
begin --3
process (Clock) begin --4
if Clock = '1' and Clock'EVENT then --5
case State is --6
when Off => if Key = '1' then State <= Armed; end if; --7
when Armed => if Key = '0' then State <= Off; --8
elsif Trip = '1' then State <= Ringing; --9
end if; --10
tSU (external) > tSU (internal) – (clock delay) + (data delay
ASICs... THE COURSE 13.8 Formal Verification 23
when Ringing => if Key = '0' then State <= Off; end if; --11
end case; --12
end if; --13
end process; --14
Ring <= '1' when State = Ringing else '0'; --15
end RTL; --16
library cells; use cells.all; // ...contains logic cell models --1
architecture Gates of Alarm is --2
component Inverter port(i : in BIT;z : out BIT) ; end component; --3
component NAnd2 port(a,b : in BIT;z : out BIT) ; end component; --4
component NAnd3 port(a,b,c : in BIT;z : out BIT) ; end component; --5
component DFF port(d,c : in BIT; q,qn : out BIT) ; end component; --6
signal State, NextState : BIT_VECTOR(1 downto 0); --7
signal s0, s1, s2, s3 : BIT; --8
begin --9
g2: Inverter port map ( i => State(0), z => s1 ); --10
g3: NAnd2 port map ( a => s1, b => State(1), z => s2 ); --11
g4: Inverter port map ( i => s2, z => Ring ); --12
g5: NAnd2 port map ( a => State(1), b => Key, z => s0 ); --13
g6: NAnd3 port map ( a => Trip, b => s1, c => Key, z => s3 ); --14
g7: NAnd2 port map ( a => s0, b => s3, z => NextState(1) ); --15
g8: Inverter port map ( i => Key, z => NextState(0) ); --16
state_ff_b0: DFF port map --17
( d => NextState(0), c => Clock, q => State(0), qn => open ); --18
state_ff_b1: DFF port map --19
( d => NextState(1), c => Clock, q => State(1), qn => open ); --20
end Gates; --21
13.8.2 Understanding Formal Verification
Key terms and concepts: The formulas to be proved are generated as proof statements ? An
axiom is an explicit or implicit fact (signal of type BITmay only be'0'and '1') ? An assertion
is derived from a statement placed in the HDL code ? implication ? equivalence
24 SECTION 13 SIMULATION ASICS... THE COURSE
assert Key /= '1' or Trip /= '1' or NextState = Ringing
report "Alarm on and tripped but not ringing";
13.8.3 Adding an Assertion
Key terms and concepts: “The axioms of the reference model do not imply that the assertions
of the reference model imply the assertions of the derived model.” Translation: “These two
architectures differ in some way.”
<E> Assertion may be violated
SEVERITY: ERROR
REPORT: Alarm on and tripped but not ringing
FILE: .../alarm-rtl3.vhdl
FSM: alarm-rtl3
STATEMENT or DECLARATION: line8
.../alarm-rtl3.vhdl (line 8)
Context of the message is:
(key And trip And memoryofdriver__state(0))
case State is --1
when Off => if Key = '1' then State <= Armed; end if; --2
when Armed => if Key = '0' then State <= Off; --3
elsif Trip = '1' then State <= Ringing; --4
end if; --5
when Ringing => if Key = '0' then State <= Off; end if; --6
end case; --7
Prove (Axiom_ref => (Assert_ref => Assert_der))
Formula is NOT VALID
But is VALID under Assert Context of alarm-rtl3
Implication and equivalence
A B A ? B A ? B
F F T T
F T T F
T F F F
T T T T
ASICs... THE COURSE 13.9 Switch-Level Simulation 25
13.8.4 Completing a Proof
...
case State is
when Off => if Key = '1' then
if Trip = '1' then NextState <= Ringing;
else NextState <= Armed;
end if;
end if;
when Armed => if Key = '0' then NextState <= Off;
elsif Trip = '1' then NextState <= Ringing;
end if;
when Ringing => if Key = '0' then NextState <= Off; end if;
end case;
...
13.9 Switch-Level Simulation
Key terms and concepts: The switch-level simulator is a more detailed level of simulation than
we have discussed so far ? Example: a true single-phase flip-flop using true single-phase
clocking (TSPC)
13.10 Transistor-Level Simulation
Key terms and concepts: transistor-level simulation or circuit-level simulation ? SPICE (or
Spice, Simulation Program with Integrated Circuit Emphasis) developed at UC Berkeley
13.10.1 A PSpice Example
Key terms and concepts: PSpice input deck
OB September 5, 1996 17:27
.TRAN/OP 1ns 20ns
.PROBE
cl output Ground 10pF
VIN input Ground PWL(0us 5V 10ns 5V 12ns 0V 20ns 0V)
VGround 0 Ground DC 0V
Vdd +5V 0 DC 5V
m1 output input Ground Ground NMOS W=100u L=2u
26 SECTION 13 SIMULATION ASICS... THE COURSE
m2 output input +5V +5V PMOS W=200u L=2u
.model nmos nmos level=2 vto=0.78 tox=400e-10 nsub=8.0e15 xj=-0.15e-6
+ ld=0.20e-6 uo=650 ucrit=0.62e5 uexp=0.125 vmax=5.1e4 neff=4.0
+ delta=1.4 rsh=37 cgso=2.95e-10 cgdo=2.95e-10 cj=195e-6 cjsw=500e-12
+ mj=0.76 mjsw=0.30 pb=0.80
.model pmos pmos level=2 vto=-0.8 tox=400e-10 nsub=6.0e15 xj=-0.05e-6
+ ld=0.20e-6 uo=255 ucrit=0.86e5 uexp=0.29 vmax=3.0e4 neff=2.65
+ delta=1 rsh=125 cgso=2.65e-10 cgdo=2.65e-10 cj=250e-6 cjsw=350e-12
+ mj=0.535 mjsw=0.34 pb=0.80
.end
(a) (b)
A TSPC (true single-phase clock) flip-flop
(a) The schematic (all devices are W/L=3/2)
(b) The switch-level simulation results
The parameter chargeDecayTime sets the
time after which the simulator sets an undriven
node to an invalid logic level (shown shaded).
DC
QNN1
N2P1
P2P3
chargeDecayTime =5ns
0 100 time/ns
chargeDecayTime = ∞
ASICs... THE COURSE 13.10 Transistor-Level Simulation 27
13.10.2 SPICE Models
28 SECTION 13 SIMULATION ASICS... THE COURSE
Key terms and concepts: SPICE parameters ? LEVEL=3 parameters
SPICE transistor model parameters (LEVEL=3)
param-
eter
n-ch.
value
p-ch.
value Units Explanation
CGBO 4.0E-10 3.8E-10 Fm–1 Gate–bulk overlap capacitance (CGBoh, not
CGBzero)
CGDO 3.0E-10 2.4E-10 Fm–1 Gate–drain overlap capacitance (CGDoh, not CGDz-
ero)
CGSO 3.0E-10 2.4E-10 Fm–1 Gate–source overlap capacitance (CGSoh, not
CGSzero)
CJ 5.6E-4 9.3E-4 Fm–2 Junction area capacitance
CJSW 5E-11 2.9E-10 Fm–1 Junction sidewall capacitance
DELTA 0.7 0.29 m Narrow-width factor for adjusting threshold voltage
ETA 3.7E-2 2.45E-2 1 Static-feedback factor for adjusting threshold voltage
GAMMA 0.6 0.47 V0.5 Body-effect factor
KAPPA 2.9E-2 8 V–1 Saturation-field factor (channel-length modulation)
KP 2E-4 4.9E-5 AV–2 Intrinsic transconductance (μCox, not 0.5μCox)
LD 5E-8 3.5E-8 m Lateral diffusion into channel
LEVEL 3 none Empirical model
MJ 0.56 0.47 1 Junction area exponent
MJSW 0.52 0.50 1 Junction sidewall exponent
NFS 6E11 6.5E11 cm–2V–1 Fast surface-state density
NSUB 1.4E17 8.5E16 cm–3 Bulk surface doping
PB 1 1 V Junction area contact potential
PHI 0.7 V Surface inversion potential
RSH 2 ?/square Sheet resistance of source and drain
THETA 0.27 0.29 V–1 Mobility-degradation factor
TOX 1E-8 m Gate-oxide thickness
TPG 1 -1 none Type of polysilicon gate
U0 550 135 cm2V–1s–1 Low-field bulk carrier mobility (Uzero, not Uoh)
XJ 0.2E-6 m Junction depth
VMAX 2E5 2.5E5 ms–1 Saturated carrier velocity
VTO 0.65 -0.92 V Zero-bias threshold voltage (VTzero, not VToh)
ASICs... THE COURSE 13.11 Summary 29
13.11 Summary
Key terms and concepts: Behavioral simulation can only tell you only if your design will not work
? Prelayout simulation estimates of performance ? Finding a critical path is difficult because you
need to construct input vectors to exercise the model ? Static timing analysis is the most widely
used form of simulation ? Formal verification compares two different representations. It cannot
prove your design will work ? Switch-level simulation can check the behavior of circuits that may
not always have nodes that are driven or that use logic that is not complementary ? Transistor-
level simulation is used when you need to know the analog, rather than the digital, behavior of
circuit voltages ? trade-off in accuracy against run time
PSpice parameters for process G5 (PSpice LEVEL=4)
.MODEL NM1 NMOS LEVEL=4
+ VFB=-0.7, LVFB=-4E-2, WVFB=5E-2
+ PHI=0.84, LPHI=0, WPHI=0
+ K1=0.78, LK1=-8E-4, WK1=-5E-2
+ K2=2.7E-2, LK2=5E-2, WK2=-3E-2
+ ETA=-2E-3, LETA=2E-02, WETA=-5E-3
+ MUZ=600, DL=0.2, DW=0.5
+ U0=0.33, LU0=0.1, WU0=-0.1
+ U1=3.3E-2, LU1=3E-2, WU1=-1E-2
+ X2MZ=9.7, LX2MZ=-6, WX2MZ=7
+ X2E=4.4E-4, LX2E=-3E-3, WX2E=9E-4
+ X3E=-5E-5, LX3E=-2E-3, WX3E=-1E-3
+ X2U0=-1E-2, LX2U0=-1E-3, WX2U0=5E-3
+ X2U1=-1E-3, LX2U1=1E-3, WX2U1=-7E-4
+ MUS=700, LMUS=-50, WMUS=7
+ X2MS=-6E-2, LX2MS=1, WX2MS=4
+ X3MS=9, LX3MS=2, WX3MS=-6
+ X3U1=9E-3, LX3U1=2E-4, WX3U1=-5E-3
+ TOX=1E-2, TEMP=25, VDD=5
+ CGDO=3E-10, CGSO=3E-10, CGBO=4E-10
+ XPART=1
+ N0=1, LN0=0, WN0=0
+ NB=0, LNB=0, WNB=0
+ ND=0, LND=0, WND=0
* n+ diffusion
+ RSH=2.1, CJ=3.5E-4, CJSW=2.9E-10
+ JS=1E-8, PB=0.8, PBSW=0.8
+ MJ=0.44, MJSW=0.26, WDF=0
*, DS=0
.MODEL PM1 PMOS LEVEL=4
+ VFB=-0.2, LVFB=4E-2, WVFB=-0.1
+ PHI=0.83, LPHI=0, WPHI=0
+ K1=0.35, LK1=-7E-02, WK1=0.2
+ K2=-4.5E-2, LK2=9E-3, WK2=4E-2
+ ETA=-1E-2, LETA=2E-2, WETA=-4E-4
+ MUZ=140, DL=0.2, DW=0.5
+ U0=0.2, LU0=6E-2, WU0=-6E-2
+ U1=1E-2, LU1=1E-2, WU1=7E-4
+ X2MZ=7, LX2MZ=-2, WX2MZ=1
+ X2E= 5E-5, LX2E=-1E-3, WX2E=-2E-4
+ X3E=8E-4, LX3E=-2E-4, WX3E=-1E-3
+ X2U0=9E-3, LX2U0=-2E-3, WX2U0=2E-3
+ X2U1=6E-4, LX2U1=5E-4, WX2U1=3E-4
+ MUS=150, LMUS=10, WMUS=4
+ X2MS=6, LX2MS=-0.7, WX2MS=2
+ X3MS=-1E-2, LX3MS=2, WX3MS=1
+ X3U1=-1E-3, LX3U1=-5E-4, WX3U1=1E-3
+ TOX=1E-2, TEMP=25, VDD=5
+ CGDO=2.4E-10, CGSO=2.4E-10, CGBO=3.8E-
10
+ XPART=1
+ N0=1, LN0=0, WN0=0
+ NB=0, LNB=0, WNB=0
+ ND=0, LND=0, WND=0
* p+ diffusion
+ RSH=2, CJ=9.5E-4, CJSW=2.5E-10
+ JS=1E-8, PB=0.85, PBSW=0.85
+ MJ=0.44, MJSW=0.24, WDF=0
*, DS=0
30 SECTION 13 SIMULATION ASICS... THE COURSE
