Linking Simulation and ATPG Vectors
To ATE
With VTRAN and VCAP
Source III, Inc.
www.sourceiii.com
Background:
Logic Simulators and ATPG programs are used
extensively for chip design, validation and to create
high fault-coverage test vectors. Simulators generate
event-based vector data (VCD, EVCD, …) during
simulation. ATPG programs generate standard cyclebased, tester oriented vectors (WGL, STIL).
The Problem:
All of this vector data needs to be translated into
test programs for specific ATE so that the device can be
tested. There are 2 flows depending on whether vector
data is event-based or cycle-based.
1
VCD File
EVCD File
$timescale
1ps
$end
$scope module test_fed $end
$var wire
$var wire
$var wire
$var wire
$var wire
$var wire
.......
$upscope $end
1
1
1
4
1
1
!
"
#
$
%
&
$enddefinitions $end
#0
$dumpvars
0&
x%
bxxxx $
x#
x"
0!
........
$end
#4879
0"
#5000
1"
#5606
1#
b0011 $
#7060
1A
#10000
0+
0/
1*
........
p_mrdy_ $end
p_mintr_ $end
p_tclk $end
p_rxd [3:0] $end
p_rclk $end
p_crs $end
$timescale
1 ns
$end
$scope module
$var port
$var port
$var port
$var port
$var port
$var port
$var port
$var port
. . . . . .
$upscope $end
top $end
1 !
clki $end
1 "
clk2x $end
1 #
vcxo_ctrl $end
1 $
bclko $end
1 %
test $end
1 &
bopt $end
[3:0] A
devid $end
1 (
dsp_only $end
$enddefinitions $end
#0
$dumpports
pa 6 6 !
pX 6 6 "
pX 6 6 #
pX 6 6 $
pa 6 6 %
pb 6 6 &
pXXXX 6666 6666 A
pa 6 6 (
$end
#1
pT 0 0 "
pD 6 0 )
#5
pD 6 0 %
pU 0 6 &
pDDDD 5555 0000 A
pD 6 0 (
pH 0 0 0
pD 6 0 4
........
2
Flow 1: event-based (VCD/EVCD) data to ATE
Simulator
VCD
EVCD
Translator
ATE
Test Program
Event-based vector characteristics
Event entry when any signal transitions
No signal direction information for VCD
Timing is embedded in event data
Translation requirements:
Cyclizing Required (convert event-based to cycle-based)
State character translations
Identify/Specify Timing
Determine Signal Direction
Bidirectional Signal I/O data separation
Significant User input required
3
STIL File
STIL 1.0 ;
Signals {
out0 Out;
SDI0 In { ScanIn; }
SDO1 Out { ScanOut; }
BCK0 In;
. . . . . .
SignalGroups {
Group_1 = 'in0 + in1 + in2 + clk1 + clk2
+ SDI0 + SDI1 + ACK0 + BCK0';
. . . . .
Timing {
WaveformTable TS1 {
Period '90ns' ;
Waveforms {
out0 { HLXT { '0ns' X; '10ns' H/L/X/T; } }
out1 { HLXT { '0ns' X; '10ns' H/L/X/T; } }
BCK0 { 10 { '0ns' D; '60ns' U/D; '70ns' D; } }
. . . . .
ScanStructures {
ScanChain Chain1 {
ScanLength 4 ;
ScanIn SDI0 ;
ScanOut SDO0 ;
ScanCells ........ ;
. . . . .
MacroDefs {
"_scan_op_" {
Shift { V {
SDI0 = #; SDO0 = #;
SDO0 = #; SDO1 = #;
} }
. . . . . .
Pattern "_pattern_" {
W TS4;
V { // 0
Group_1 = NNN00NN00;
Group_3 = XXXXX;
}
C { // 100
Group_1 = NNN000011;
}
Macro "_scan_op_" {
SDI0 = 0010; SDO0 = XXHL;
SDI1 = 0001; SDO1 = XXLL;
}
V { // 500
Group_1 = 010001100;
}
W TS1;
V { // 600
Group_1 = 100000100;
}
Loop 12 {
W TS4
V { // 690
Group_1 = NNN00NN01;
Group_3 = XXXXX;
}
}
. . . . . . .
}
4
WGL File
waveform design
signal
"si" : input;
"se" : input;
"pi1" : input;
"pi2" : input;
"pi3" : input;
"ck_Epulse" : input;
"ck_Ppulse" : input;
"po" : output;
"so" : output;
end
timeplate "_default_WFT_" period 100ns
"si" := input [0ps:S];
"se" := input [0ps:S];
"ck_Ppulse" := input [0ps:Z, 50ns:D, 60ns:S, 80ns:D];
"ck_Epulse" := input [0ps:D, 20ns:S, 40ns:D, 50ns:Z];
"po" := output [0ps:X, 35ns:Q'window, 55ns:X];
"so" := output [0ps:X, 10ns:Q'edge];
. . . . . .
end
scancell
"Flop1"; "Flop2";
ccG ["Flop2", "Flop1" ];
end
scanstate
{ non_tester_ready_master_data }
{ scan_test }
ccU0 := ccG(XX);
ccL0 := ccG(01);
ccU1 := ccG(10);
ccL1 := ccG(01);
. . . . .
pattern group_ALL ("si", "se", "pi1", "pi2", "pi3",
"ck_Epulse", "ck_Ppulse", "po", "so")
{ test_setup }
vector("_default_WFT_") := [ X X X X X 0 0 X X ];
vector("_default_WFT_") := [ X X X X X 0 0 1 0 ];
vector("_default_WFT_") := [ 1 0 X X X 0 0 X 1 ];
repeat 25
vector("_default_WFT_") := [ X X X X X 0 0 X X ];
{ scan_test }
{ pattern 0 }
{ load_unload }
scan("_default_WFT_") := [ - 1 X X X 0 1 X - ],
output [cc:ccU0], input [cc:ccL0];
{ vector_capture }
vector("_other_WFT_") := [ 1 0 1 1 1 1 1 X X ];
. . . . .
end
end
scanchain
cc ["si", "Flop1", "Flop2", "so" ];
end
5
Flow 2: cycle-based (WGL/STIL) data to ATE
ATPG
WGL
STIL
Translator
ATE
Test Program
Cycle-based vector characteristics
All signal name and direction information included
All timing and waveform information included
High-level language constructs may be used
Possible scan data defined
Translation requirements:
Flatten or maintain scan
State character translations
Minimal User input required
6
VTRAN
Vector data translation for Simulation & Test
7
VTRAN overview
• Bridging simulation & test formats
 Simulation & ATPG-generated translations
 Comprehensive vector processing options
• Large number of canned readers
 STIL, WGL, VCD/EVCD, TDL_91, TSTL2, FSDB, FTDL
nanosim, VCL, … + User-Programmed Reader
• Numerous formatters for testers & EDA
 STIL, WGL, Verigy, Credence, Teradyne, Advantest, IMS,
Verilog testbench, VHDL testbench, TSTL2, ….
• Nearly 20 years of success in hundreds of customer
applications
 OEM’ed by Synopsys and Cadence for over 15 years
 Used by Qualcomm, TI, Broadcom, Apple, Microsoft, Marvell,
TSMC, Xilinx, Nvidia, Micron, AMD, AMI, Cisco, …
8
VTRAN basic Flow
VTRAN
Tools
ATPG
Simulators
Vector
Formats
VCD/EVCD
WGL
STIL
…
OVF
TVF
Original
Vector File
Target
Vector File
Test Program
Verigy
Advantest
Teradyne . . .
Circuit Simulator
SPICE, HSPICE
Synopsys
TimeMill
PowerMill
NanoSim . . .
Processing
Command
File
Logic Simulation/
verification
VerilogTestbench
VHDL Testbanch
STIL
WGL
TSTL2 …
9
VCD/EVCD-to-ATE VTRAN FLOW
(errors)
VTRAN
Simulation
VCD/
EVCD
•Cyclize vectors
•State Trans
•Define Timing
•Signal Direction
•Masking
•other processing
Virtual
Test Program
Verification
VTRAN
ReadBack
ATE-to-Testbench
ATE Test
Program &
Timing
Verilog
Verification
Testbench
OK ?
ATE
Verification
Simulation
1. Simulation of final design generates VCD/EVCD file.
2. VTRAN performs cyclization, state mapping, makskng and other optional processing to generate ATE test program
3. In Virtual Test Program Verification, VTRAN ReadBack translates ATE test program to verification testbench.
4. Verification Simulation verifies test program – can be run with varying parameter corners.
5. If OK, then ATE test program is ready for tester.
6. If errors, then correlate to design or adjust VTRAN parameters.
10
VTRAN – cyclizing event vector data (vcd/evcd):
For single timeset data – use align_to_cycle
- User specifies cycle time
- User specifies signal sample points
- User specifies timing for output file
- VTRAN translates event- to cycle-based
For multiple timeset data use template_cyclization
- User specifies cycle time, sample points, and
timing for each timeset
- User specifies matching criteria for each timeset
- VTRAN matches timeset criteria to event data
to select the appropriate timesets and performs
event- to cycle-based translation
11
VTRAN Vector Processing
template_cyclization example:
TEMPLATE_CYCLIZATION
CYCLIZATION_SKEW = "0.5" ,
TERMINATE_ON_DEFAULTS = "20",
MATCH_REPORT = "designfile.rpt",
MATCH_TRACE_START = 1 ;
MATCH_TRACE_STOP = 8 ;
VIEW_OUTPUT = "designfile.view" ;
TIMESET SCAN_SHIFT
CYCLE 3.2;
PINTYPE NRZ * @ 0.5, 0.1;
PINTYPE -PRIMARY RZ cpref_clk @ 1.0, 2.0;
PINTYPE STB * @ 3.0, 3.1;
IDENTIFIER (scan_load=1)&(scan_enb=1) ;
ENDTIMESET;
TIMESET CAPTURE
CYCLE 6.4;
PINTYPE NRZ * @ .8, .1;
PINTYPE -PRIMARY RZ cpref_clk @ 2.0, 4.5;
PINTYPE -PRIMARY -ACTIVE_ONLY RO ubf_clk @ 1.5, 4.8;
PINTYPE STB * @ 6.1, 6.2;
IDENTIFIER (scan_load=0)&(scan_enb=1) ;
ENDTIMESET;
TIMESET RUN
CYCLE 4.0;
WEIGHT 1 ;
SAMPLE_POINT all_inputs @ 2.5;
PINTYPE NRZ * @ .4, .1;
PINTYPE -PRIMARY RZ cpref_clk @ 2.0, 3.0;
PINTYPE -PRIMARY RO ubf_clk @ 1.0, 3.2;
PINTYPE STB * @ 3.5, 3.6;
IDENTIFIER scan_enb = 0 ;
ENDTIMESET;
12
VTRAN Vector Processing
Add_Pin examples:
ADD_PIN
newpin
INPUT = 0;
ADD_PIN IOX BIDIRECT = ZX ;
ADD_PIN notclk input = 1 WHEN clk = 0 :
= 0 OTHERWISE ;
ADD_PIN ORpin input
=
=
=
=
1
1
1
0
WHEN pin1
WHEN pin2
WHEN pin3
OTHREWISE
= 1 :
= 1 :
= 1 :
;
ADD_PIN newclk INPUT = 1 ;
PINTYPE RZ newclk @ 25, 50 ; { creates constant clock }
13
VTRAN Vector Processing
mask_pins examples:
Very useful for debugging and cleaning-up test vector sets in
translations from VCD/EVCD event files. Remove spurrious glitches,
mask high-speed transitions, force initialization states.
MASK_PINS gpio1 @ 0, 700 ;
// cycle time = 100ns
gpio1 input state stream:
1100010111000000
gpio1 output state stream:
XXXXXXX111000000
MASK_PINS mask_character=1 gpio1 @ CONDITION err0=0 ;
err0 input state stream:
1111110000011111
gpio input state stream:
1110000000000000
gpio output state stream:
1110001111100000
MASK_PINS gpio1 @ TRANSITION 0->1, -4, +2 ;
gpio1 input state stream: 0000000011111111
gpio1 output state stream:
0000XXXXXX111111
MASK_PINS gpio1 @ SEQUENCE “00011111000”, “00XX1111XX0” ;
gpio1 input state stream:
1111000111110001
gpio1 output state stream:
111100XX1111XX01
14
VTRAN Vector Processing
mask_pins examples (continued):
MASK_PINS gpio1 @ CONTROL_TRANSITION ctrl1 0->1, -2, +3 ;
ctrl1 input state stream: 0000000011111111
gpio1 input state stream: 0011000011000111
gpio1 result state stream:
001100XXXXXX0011
MASK_PINS gpin1 @ TIMESET tset1 ;
MASK_PINS mask_character = “~pinA” pinX @ 1 ;
pinA input state stream: 0001110001110000
pinX
result state stream:
1110001110001111
MASK_PINS pinA @ CONDITION (err0=0)&(rel(-1)=0)&(err0(+1)=1) ;
err0 input state stream:
1111110000011111
rel input state stream:
1111111100000000
pinA input state stream: 0001110001110000
pinA
input
state stream:
0001110001X10000
15
VTRAN Vector Processing
Using Registers:
The REGISTER command supports the concept of a memory, or
register, element that can be used in a compound logic expression. The
basic idea is to provide a means whereby the occurance of an event
(logic condition or time) can be remembered and used as part of a logic
expression for other vtran statements.
REGISTER R1 init=0, set @ TIME 0 :
clear @ CONDITION (Reset=0)&(Run=1);
REGISTER Rmask init = 0, set @ CONDITION Pak=1 :
clear @ CONDITION (Pak=0)&(enb=1) ;
MASK_PINS all_outputs @ CONDITION Rmask=1 ;
16
VTRAN Vector Processing
bidirect_control examples:
For VCD translations, it is necessary to provide a mechanism by which
VTRAN can determine the direction of state data on bidirectional
signals. This is not necessary for EVCD, WGL or STIL files.
BIDIRECT_CONTROL gpio[12:0] = input WHEN dirctl = 0 ;
gpio bus is in input mode when dirctl is a logic 0
BIDIRECT_CONTROL gpio[6:0] = output WHEN (enb=1)&(dirctl=1) ;
gpio bus is in output mode when both enb and dirctl are logic 1
BIDIRECT_CONTROL gpio[8:5] = input WHEN dir = 0, DEFAULT_INPUT = N ;
gpio bus is in input mode when dir is logic 1, when in output
mode input track is N state.
17
Example VTRAN command script
OVF_BLOCK
BEGIN
{ Specify how to read input file }
orig_file = "sbc2.vcd";
SCRIPT_FORMAT verilog_vcd;
BIDIRECTS PAD_ICE_DATA[7:0];
INPUTS PAD_ICE_ADDR[15:0];
INPUTS PAD_ICE_EN_B;
BIDIRECTS PAD_PORTA;
BIDIRECTS PAD_PORTB[4:0];
OUTPUTS PAD_ICE_RST_O;
OUTPUTS PAD_ICE_IRQ_O;
INPUTS PAD_ICE_DATA[7:0];
INPUTS PAD_PORTB_ctl[4:0];
. . . .
PROC_BLOCK
BEGIN
{ Processing to be done on vectors }
cycle 100;
{10 MHz cycle}
BIDIRECT_CONTROL PAD_PORTA=input WHEN PAD_PORTA_ctl=1;
BIDIRECT_CONTROL PAD_ICE_DATA=input WHEN PAD_ICE_DATA_ctl=1;
BIDIRECT_CONTROL PAD_PORTB[4]=input WHEN PAD_PORTB_ctl[4]=1;
BIDIRECT_CONTROL PAD_PORTB[3]=input WHEN PAD_PORTB_ctl[3]=1;
. . . .
TVF_BLOCK
BEGIN
{ specify output file format }
tester_format HP93000 ,
-auto_group,
-DVC_OUTPUTS_FNZ,
XMODE = "ts1 3",
XMODE_MAP = "sbc2.map",
PIN_CONFIG_FILE = "sbc2.pin",
PINSCALE = "128",
TIME_STAMPS = "ON",
DVC_FILE = "sbc2.dvc"
REPEAT_THRESHOLD = "4"
;
TARGET_FILE = "sbc2.avc"; {output file }
END;
END;
ALIGN_TO_CYCLE 100, ALL_INPUTS @ 10, ALL_OUTPUTS @ 95 ,
PAD_XIN @ 40, PAD_XCIN @ 30;
PINTYPE
PINTYPE
PINTYPE
PINTYPE
NRZ * @ 10 ;
STB * @ 95 ;
RO PAD_XIN @ 30, 50;
SBC PAD_XCIN @ 20, 40;
STATE_TRANS outputs '0'->'L', '1'->'H', '-'->'X',
'x'->'X', 'z'->'X' 'Z'->'X';
STATE_TRANS pure_inputs 'X'->'0', 'x'->'0', 'z'->'Z';
STATE_TRANS bidir_inputs 'X'->'0', 'x'->'0', 'z'->'Z';
END;
18
VTRAN ReadBack modules:
This is an important feature for all tester interfaces,
particularly for translations from event-based vector files like
VCD and EVCD.
• Significant user input can result in errors
• Validates the VTRAN-generated test program
• Uses Virtual ATE testbench simulation
• Debug test program before silicon
• Saves costly ATE test time
VTRAN-generated
ATE test program
OK ?
Virtual
Test Program
Verification
VTRAN
ReadBack
ATE-to-Testbench
Verilog
Verification
Testbench
Verification
Simulation
19
STIL/WGL-to-ATE VTRAN FLOW
(errors)
VTRAN
ATPG
Synopsys
Cadence
Mentor
STIL/
WGL
•Scan data
•Multiple timesets
•ATE parameters
Virtual
Test Program
Verification
VTRAN
ReadBack
ATE-to-Testbench
ATE Test
Program &
Timing
Verilog
Verification
Testbench
OK ?
ATE
Verification
Simulation
1. ATPG run on final design generates STIL/WGL file.
2. VTRAN handles scan data and multiple timesets to generate ATE test program. Minimal user input required.
3. For Virtual Test Program Verification, VTRAN ReadBack translates ATE test program to verification testbench.
4. Verification Simulation verifies test program – can be run with varying parameter corners.
5. If OK, then ATE test program is ready for tester.
6. If errors, then correlate to design or ATPG for remedies.
20
VTRAN Support for Verigy 9300
 Generates ASCII format file (for v2b utility)
 Supports scan data (can also flatten scan)
 Supports multiple timesets
 Full support forRepeats and Loops from STIL/WGL files.
 Also discovers Repeats and Loops in VCD/EVCD files for
compression.
• Repeat_Threshold feature
• Loop_Threshold feature
 X-mode support
• Up to 8X
• Selectable by individual timeset
• Cumulative timing and pin-maps for multiple vector files
• Pinscale support
• Padding via default or padding file
• Create Signal Groups
21
VTRAN Support for Verigy 93000 (cont.)
 File merging
• Can merge parallel vector files with overlapping or non-overlapping
signals
• Can merge sequential vector files
 ReadBack module for test program validation via Verilog or
VHDL testbench.
 Actively adding new support features.
22
VTRAN Support for Terdyne testers
 Catalyst, J750, J971/973, UltraFLEX supported
 Support for scan data and multiple timesets
 Full support Repeats and Loops from STIL/WGL files. Also
discovers Repeats and Loops in VCD/EVCD files for
compression.
 For J750 and uFLEX supports Basic Timing and Formulas
as well as standard tsets/esets files.
 File merging
 ReadBack modules for test program verification via Verilog
testbench.
 uFLEX supports dual mode and x2/x4/x8/extended scan
types.
23
VTRAN Support for other testers
 Advantest T66xx, T33xx and T2000
 Credence (SWAV) and Saphire (STIL)
 Q-Star IDDQ tester
 HP94000
 IMS
 Trillium
 LTX
 Schlumberger ITS9000
 ASIC formats: TDL_91, TSTL2, FTDL
 Others under development per customer requests.
24
VTRAN Additional Processing Features
Merging Multiple Input Files:
Multiple input files can be merged using VTRAN with the MERGE_FILE
directive in the OVF_BLOCK :
OVF_BLOCK
BEGIN
TABULAR_FORMAT WGL –cycle ;
MERGE_FILE –concatenate
ORIG_FILE = “SET1.wgl”;
END_MERGE;
MERGE_FILE
ORIG_FILE = “SET2.wgl”;
END_MERGE;
MERGE_FILE
ORIG_FILE = “SET3.wgl”;
END_MERGE;
END;
PROC_BLOCK
BEGIN
. . .
25
VTRAN Additional Processing Features
IDDQ Control & Vector Insertion:
A general-purpose IDDQ vector insertion capability which provides for the
insertion of up to 3 control/data signals and any number of IDDQ vectors into
WGL or STIL files that have been generated with IDDQ markers.
IDDQ
IDDQfile = "iddqfname",
Keyword = "measureIDDQ"
Q_CLK = "1", { optional }
Q_MD = "1" { optional }
;
26
VTRAN comparison to competitors:
VTRAN/VCAP
Wavewizard
TSSI
User Interface
script
GUI
GUI
Learning Curve
1-2 days
1-2 weeks
2 weeks
Readers
> 20
3 or 4
3 or 4
Vector
Conditioning
Excellent
Fair
Good
Timing Analysis
Tool
Yes
Yes
Yes
Virtual Test
Included
Extra
Extra
Cost
Low
Medium
High
27
VTRAN SUMMARY
 Comprehensive Translation Support - VTRAN™ supports over 30
vector and ATE formats including WGL, STIL, TDL_91, VCD/EVCD,
Teradyne, Verigy, Cadence, LTX, Advantest, IMS and many more.
 Ease of Use - VTRAN™ has a typical learning time of 2-6 hours for
many translation applications.
 Text/Srcipt Based - VTRAN™ is a batch compiler that is driven by a
command script created by the user. User maintains full control over the
process.
 Over 25 Years in Business - VTRAN™ was introduced in 1990.
Thousands of successful translations done.
 Large Customer Base - Texas Instruments, AMD, Apple, Microsoft,
Broadcom, Synopsys (OEM), Cadence (OEM), Infineon, Honeywell, Marvell,
NXP, Qualcomm,...
 Excellent Documentation - Vtran™ User's Guide , INTERFACES
directory with numerous example translations, Extensive Application
Notes - all available online.
28
VTRAN SUMMARY (continued)
 Powerful Editing Features - Adding/Deleting signals, Masking
signals (equation-based, sequence-based, time-based), name aliasing,....
 Powerful Vector Processing Features - Repeat count control
(expansion, accumulation, max count), Loop control (expension,
accumulation, max count), File Merging, Insert Statements, Data Shifting,
Event Registers, Cyclization,....
 Blazing Speed - VTRAN™ can translate GigaByte files in minutes.
 Outstanding Technical Support - Source III is highly responsive to
all customer needs. New features are often added within days to meet
customer needs. We provide you with personlized technical support.
 Low Cost!! - VTRAN™ is the lowest cost, full-feature, validated vector
translation program on the market.
29
VCAP
Vector Analysis Program
VCAP Extracts edge timing, waveform behavior and
statistical information from event-based files like VCD and
EVCD. It can serve as a front-end to VTRAN for cyclization.
Reports
VCD/
EVCD
VCAP
Timing file
for VTRAN
30
VCAP Analysis Features:
Handles wide variety of event-based vector formats
•VCD, EVCD
•Nanosim, Novas FSDB, Mentor Log files, tabular,
…
Checks for Max Delays
Analyses signal timing & behavior for single timeset
Checks for signal glitches
Illegal state checking
Checks for simultaneous transitions
Checks for output signal stability
Generate timing file for direct import into VTRAN
31
Thank You for your attention !
QUESTIONS ?
32