RTSX-S and RTSX-SU Reliability Test Vehicles Daniel K. Elftmann Director Product Engineering Richard Katz Head Grunt Office of Logic Design Igor Kleyner Deputy Grunt Office of Logic.
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Transcript RTSX-S and RTSX-SU Reliability Test Vehicles Daniel K. Elftmann Director Product Engineering Richard Katz Head Grunt Office of Logic Design Igor Kleyner Deputy Grunt Office of Logic.
RTSX-S and RTSX-SU
Reliability Test Vehicles
Daniel K. Elftmann
Director Product Engineering
Richard Katz
Head Grunt Office of Logic Design
Igor Kleyner
Deputy Grunt Office of Logic Design
September 8th, 2004
Background
Background
In 2003, some customers reported clusters of failures
Customer failures had some common factors
Stressful designs
I/O and/or power supplies exceeding datasheet limits
Failures occur early in device life
Actel investigation indicated isolated programmed antifuses were failing to a
higher impedance state
Industry investigation
Actel working closely with Industry Tiger Team (ITT) led by The Aerospace Corp.
Participants include Lockheed Martin, Boeing, General Dynamics, Northrop Grumman
Space Technology, JPL, NASA
A series of experiments are being conducted to investigate the customer failures
Remainder of presentation describes the two different Test Vehicles being used for the
following experiments
Industry Tiger Team Design
NASA Test Design
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Industry Tiger Team Design
Top Level Block Diagram
zoom_sel_n
zoom[1:0]
1,146 Stage
Slow Ring
Oscillator
2
delay_out
ResetSyncD
Reset_n
Set_n
Clksel[2:0]
Clk_ext
ShiftFreq[1:0]
A_Pattern_type
A_Pattern_length[2:0]
707 Bit
Array
Shift
Register
3
2
3
A_Monitor
OE
Clk_o_sel
A0S
B1
S
IO_Pattern_type
IO_Pattern_length[2:0]
TOG_n
140 Bit
I/O
Shift
Register
3
IO_pin[1]
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Freq_out
IO_Monitor
IO_pin[139]
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Industry Tiger Team Design
1,146 Stage Slow Ring Oscillator
ResetSyncD
zoom[1]
zoom[0]
Monitor
zoom_sel_n
S
A0
D
B1
S
S
A0
SET
CLR
Q
Delay_out
Q
B1
S
0
1
2
3
S
A0
B1
S
R-Cell CLR has
priority over SET
ResetSyncD
Delay Line TPDL
Delay_out
Delay Line TPDH
Synchronized Reset input assures clean startup of slow ring oscillator
Delta Read & Record must be done via frequency measurement
No mechanism to break ring and measure delay directly
Zoom Debug feature
Allows for enhanced isolation of delays during debug only
Long oscillator frequency stabilization time of ~15 minutes at startup
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Industry Tiger Team Design
Slow Oscillator Startup
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
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Industry Tiger Team Design
140 Bit I/O Shift Register
I/O Reset Block
IO_SetSyncD
Set_n
Startup
Synchronizer
Reset_n
3
Clksel[2:0]
Clk_ext
IO_Clock
2
ShiftFreq[1:0]
IO_Pattern_length[2:0]
IO_Pattern_type
50MHz
Ring
Oscillator
D=0
IO_ResetSyncD
Shift
Enable
Control
IO_Shift_enable_n
Monitor
3
Pattern
Generator
I/O Weave Shift
Register
Serial
Pattern
Checker
IO_Monitor
Monitor Pin Behavior
Startup
Test OK
Error
Independent controls to set
Pattern generator toggle rate for internal R-Cells
16 unique patterns possible, with range of toggle rates (more later)
Clock generated via internal 15 stage ring oscillator (~50MHz)
Dedicated Startup Synchronization circuitry for IO_clock domain
IO_Monitor indicates pass/fail
On-chip self-checking circuitry detects and latches detected errors
Note: not all errors are detectable by self-test
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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Industry Tiger Team Design
Ring Oscillator
Optional Buffer: D = 1 installed
D = 0 do not install
Clk_ext
U1 U2
U14 U15
1
0
S
D
Q
CLKINT
2
E
Clock_out
CLR
D
Q
4
E
CLR
D
Q
8
E
CLR
D
Q
16
E
CLR
D
Q
32
Sliding
Decoder
E
CLR
D
Q
64
E
CLR
Reset_n
clksel[2]
clksel[1]
clksel[0]
Division
ClkSel[2:0] Factor
000
001
010
011
100
101
110
111
na
2
2
4
1
16
32
64
Approximate
Frequency
(MHz)
Clk_ext
25.00
25.00
12.50
50.00
3.13
1.56
0.78
Ring Oscillator instantiated twice
1st drives Array SR, 2nd drives I/O SR
Additional delay stage inserted in Array oscillator to keep two oscillators out of sync
Ring Oscillators frequency dependent on Temperature & VCCA voltage
Ring Oscillators NOT recommended for flight designs
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Industry Tiger Team Design
Shift Enable Control
Independent Shift Enable
circuits instantiated in each
of the 2 sequential blocks
to pace R-Cell toggling
ShiftEnable_n
0
0
ShiftEnable_n fanout = 16
R-Cell U0 fan out managed
via register replication
2
ShiftFreq
0
1
2
3
Clock
A
B
C
D
1
2
3
U0
D
Q
D
SET
Q
D
SET
Q
SET
D
Q
CLR
U1
U2
U3
Both Array shift register & ResetSyncD
I/O shift register blocks set
by same input configuration
pin settings:
Clock
ResetSyncD
If ShiftFreq==00: Every Cycle
ShiftEnable_n
If ShiftFreq==01: Every 2nd Cycle
ShiftEnable_n
If ShiftFreq==10: Every 3rd Cycle
ShiftEnable_n
If ShiftFreq==11: Every 4th Cycle
ShiftEnable_n
Asserted active low enable is consistent with SX-A/S R-CELL enable polarity
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Industry Tiger Team Design
Pattern Generator
SetSyncD
0
Serial_Feedback
Pattern_Length[2:0]
1
2
4
3
5
6
7
0
1
3
4
5
6
7
01
2
3
D
E
SET
CLR
Q
D
E
SET
Q
CLR
D
E
SET
Q
CLR
D
E
SET
Q
D
E
CLR
SET
Q
CLR
D
E
SET
CLR
Q
D
E
SET
CLR
Q
D
E
SET
CLR
Q
D
E
SET
Q
Serial_Pattern
CLR
Pattern_type
Clock
ResetSyncD
ShiftEnable_n
Pattern Pattern
Type
Length
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
000
001
010
011
100
101
110
111
000
001
010
011
100
101
110
111
Code
Length
1 0 0 1
1 0 0 0 1 0 0 0 1
One hot I/O at a time switching
1 0 0 0 0 0 1 0 0 0 0 0 1
1 0 0 0 0 0 0 1 0 0 0 0 0
1 0 0 0 0 0 0 0 1 0 0 0 0 0
1 0 0 0 0 0 0 0 0 1 0 0 0 0
1 0 0 0 0 0 0 0 0 0 1 0 0 0
1 0 1 1 0 1 0 0
1 0 0 1 1 0 1 1 1 0 1 1
Wave of 0's followed by wave of
1 0 0 0 0 1 1 0 0 0 1 1 1
1 0 0 0 0 0 1 1 0 0 0 0 1
1 0 0 0 0 0 0 1 1 0 0 0 0 0
1 0 0 0 0 0 0 0 1 1 0 0 0 0
1 0 0 0 0 0 0 0 0 1 1 0 0 0
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
in entire I/O ring
0 0 0 0 0 1 0
0 1 0 0 0 0 0 0
0 0 1 0 0 0 0
0 0 0 0 1 0 0 0
0 0 0 0 0 0 1 0
0
1
0
0
0
0
0
0
0
0
0 0 1
0 0 0
0 1 0 0
0 0 0
0 0 0
0
0
1
0
0 1 0 0 0 0 0 0 1
0 0 0 0 1 0 0 0 0
0 0 0 0 0 0 0 0 1 0
0 0 1 0 0 0 0 0 0 0
0 0 1 0 0 0
1's
0 0
1 1
1
0 0
0 0
1 1 1 1 0 1 1 1 1 1 0 1 1 1 1 0 0 1 1 1
0 0 0
1 1 0
1 1
0 0
1 1 1 1 0 0 1 1 1 1 1 0 1 1 1 1 1 1
0 0 0 1 1 1 1 0 0 0 1 1 1 1 1 0 0 1 1
1 0 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 1 0
1 1 1 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 1 1
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2
3
#Bits+9
5
6
7
8
9
2
3
#Bits+9
5
6
7
8
9
Switching
Bits
Rate
2
2
2
2
2
2
2
2
1
1
1
1
1
1
1
1
Wednesday, September 8th, 2004
100.00%
66.67%
N/A
40.00%
33.33%
28.57%
25.00%
22.22%
50.00%
33.33%
N/A
20.00%
16.67%
14.29%
12.50%
11.11%
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Industry Tiger Team Design
I/O Weave Shift Register
I/O Weave block three modes of operation
Mode 1: I/O Bypass (OE=‘0’ TOG_n=‘X’)
Operates as shift register bypassing the I/Os thru 2-1 multiplexers
No I/Os toggle and are tri-stated
Middle Cell
#I/Os - 2
First Cell
Used Once
I/Os placed
sequentially around
device in order of
shift register
Middle Cell
#I/Os - 2
Last Cell
Used Once
IO_SetSyncD
IO_Serial_Pattern
1
0
1
S
D
SET
Q
S
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
Q
S
1
0
S
0
1
S
D
SET
Q
S
E
CLR
Q
S
1
0
S
0
S
D
SET
Q
IO_Feedback
S
E
CLR
Q
IO_Clock
IO_ShiftEnable_n
IO_ResetSyncD
TOG_n
OE
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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Industry Tiger Team Design
I/O Weave Shift Register
I/O Weave block three modes of operation
Mode 2: I/O Weave (OE=‘1’ TOG_n=‘1’)
Operates as shift register toggling I/O pad at pattern generator defined rate
Signal takes path thru output buffer to the pad and back into input buffer
I/O toggle rate controlled by Pattern Generator
Middle Cell
#I/Os - 2
First Cell
Used Once
I/Os placed
sequentially around
device in order of
shift register
Middle Cell
#I/Os - 2
Last Cell
Used Once
IO_SetSyncD
IO_Serial_Pattern
1
0
1
S
D
SET
Q
S
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
Q
S
1
0
S
0
1
S
D
SET
Q
S
E
CLR
Q
S
1
0
S
0
S
D
SET
Q
IO_Feedback
S
E
CLR
Q
IO_Clock
IO_ShiftEnable_n
IO_ResetSyncD
TOG_n
OE
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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Industry Tiger Team Design
I/O Weave Shift Register
I/O Weave block three modes of operation
Mode 3: All I/O Toggle (OE=‘1’ TOG_n=‘0’)
Simultaneously switches all I/Os from 0 to 1 then 1 to 0
Pattern follows shift register chain enabling pattern checker to detect errors at any point in chain
Simultaneous 100% I/O Toggle Rate
Register n+1 <= !n
Middle Cell
#I/Os - 2
First Cell
Used Once
I/Os placed
sequentially around
device in order of
shift register
Middle Cell
#I/Os - 2
Last Cell
Used Once
IO_SetSyncD
IO_Serial_Pattern
1
0
1
S
D
SET
Q
S
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
S
1
0
S
0
1
S
D
SET
Q
S
Q
E
CLR
Q
S
1
0
S
0
1
S
D
SET
Q
S
E
CLR
Q
S
1
0
S
0
S
D
SET
Q
IO_Feedback
S
E
CLR
Q
IO_Clock
IO_ShiftEnable_n
IO_ResetSyncD
TOG_n
OE
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
12
Industry Tiger Team Design
707 Bit Array Shift Register
Array Reset Block
A_SetSyncD
Set_n
Startup
Synchronizer
Reset_n
3
Clksel[2:0]
Clk_ext
A_Clock
2
ShiftFreq[1:0]
A_Pattern_length[2:0]
A_Pattern_type
50MHz
Ring
Oscillator
D=1
A_ResetSyncD
Shift
Enable
Control
A_Shift_enable_n
Monitor
3
Pattern
Generator
Array Shift Register
707 R-Cells
Serial
Pattern
Checker
A_Monitor
Monitor Pin Behavior
Array shift register has independent controls to set
Pattern generator toggle rate for internal R-Cells
Startup
Test OK
Error
Options for the Pattern Generator identical to I/O Shift Register Pattern Generator
Typical setting for Simultaneous Switching Registers (SSR) set at 12.5%
Clock generated via internal 16 stage ring oscillator (~50MHz)
Dedicated Startup Synchronization circuitry for A_Clock domain
A_Monitor indicates pass/fail
On-chip self-checking circuitry detects and latches detected errors
Note: not all errors are detectable by this self-test
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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Industry Tiger Team Design
Aerospace Experiments
Colonel Test
RT54SX32S MEC
with “old” algo
Project 4b1
Temp = ~40°C
VCCA= 2.5V
Project 7
~500 parts
Temp = ~40°C
VCCA= 2.5V
600 hrs
Project 4b2
Temp = ~40°C
VCCA= 2.5V
1000 hrs +
RT54SX32S MEC
with “new” algo
General Test
330 parts
Project 4b2
Temp = ~40°C
VCCA= 2.5V
RT54SX32S MEC
with “old” algo
83 parts
Project 4b2
83 parts
Temp = 85°C
VCCA= 3.0V
1000 hrs +
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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NASA Design
Top Level Block Diagram
delay_in
delay_sel_n[1:0]
1,236 Stage
Delay Line
2
delay_out
ResetSyncD
Reset_n
Set_n
CLKA
ShiftFreq[1:0]
A_Pattern_type
A_Pattern_length[2:0]
621 Bit
Array
Shift
Register
2
3
A_Monitor
Array_out
OE
HCLK
IO_Pattern_type
IO_Pattern_length[2:0]
TOG_n
144 Bit
I/O
Shift
Register
3
IO_pin[1]
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
IO_Monitor
IO_pin[143]
Wednesday, September 8th, 2004
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NASA Design
Header Bd. Clock & Reset Driver
NASA Office of Logic Design (OLD) designed and built solder in card to
Burn-in Board (BIB) to provide clock and reset to 8 Devices Under Test
(DUT)
Card solders into BIB configuration socket locations
Clocks for DUTs in each column can be controlled to run 180° out of phase
Clocks can be driven up to 64MHz
Jumper selectable clock dividers available on Header Board
HCLK, CLKA, and CLKB frequency independently settable
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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NASA Design
1,236 Stage Delay Line
delay_sel_n[0]
delay_sel_n[1]
1,236 NAND4 gate
Delay Line
Sliding
Decoder
Monitor
D
Q
D
Q
D
Q
D
Q
HCLK
E
CLR
E
CLR
E
E
CLR
CLR
ResetSyncD
2
Delay_in
8
128
D
0
1
2
3
SET
CLR
Q
Delay_out
Q
R-Cell CLR has
priority over SET
Configuration lines select input to delay line during operation
Synchronized Reset input insures clean startup
Direct delay delta read & record measurement possible via Delay_in
No free running oscillator & related self-heating thermal effects, therefore no startup
stabilization issues
Allows for more accurate delay measurements
Zoom feature removed as un-needed, Action Probe circuitry sufficient for debug
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
17
NASA Design
144 Bit I/O Shift Register
I/O Reset Block
IO_SetSyncD
Set_n
Startup
Synchronizer
Reset_n
IO_ResetSyncD
HCLK
2
ShiftFreq[1:0]
Shift
Enable
Control
IO_Shift_enable_n
Monitor
3
IO_Pattern_length[2:0]
IO_Pattern_type
Pattern
Generator
I/O Weave Shift
Register
Serial
Pattern
Checker
IO_Monitor
Monitor Pin Behavior
Changes
Startup
Test OK
Error
Utilizes HCLK vs. 15 stage internal ring oscillator
Industry Tiger Team design does NOT utilize the HCLK resource
HCLK driven by NASA header board add-on card
Dedicated Reset Synchronization circuitry for HCLK clock domain
Increased fan out of Shift Register Enable nets from 16 vs. 29
Exceeds maximum fan out allowed (24) in Designer Software by 20%
Number of I/Os 143 vs. 139
78 configured for 5V CMOS, remainder 5V TTL; Industry Tiger Team design all TTL
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
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NASA Design
621 Bit Array Shift Register
Array Reset Block
A_SetSyncD
Set_n
Startup
Synchronizer
Reset_n
A_ResetSyncD
CLKA
2
ShiftFreq[1:0]
A_Pattern_length[2:0]
A_Pattern_type
Shift
Enable
Control
A_Shift_enable_n
Monitor
3
Pattern
Generator
Array Shift Register
621 R-Cells
Serial
Pattern
Checker
A_Monitor
Array_out
Changes
Utilizes CLKA vs. 16 stage internal ring oscillator
CLKA driven by NASA header board add-on card
Increased fan out of Shift Register Enable nets from 16 vs. 29
Exceeds maximum fan out allowed (24) in Designer Software by 20%
Shift register R-Cells manually placed to improve utilization of Long Vertical Tracks (LVT)
and Long Horizontal Tracks (LHT)
Array_out added to increase observability at tester
Number of bits 621 vs. 707
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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NASA Design
Final Design Summary
Utilization
Post-Combiner device utilization:
SEQUENTIAL
Used: 1080 Total: 1080
COMB
Used: 1800 Total: 1800
LOGIC
Used: 2880 Total: 2880
IO w/ Clocks
Used: 168 Total: 170
CLOCK
Used: 2 Total: 2
HCLOCK
Used: 1 Total: 1
(100.00%)
(100.00%)
(100.00%) (seq+comb)
(78 CMOS) (89 TTL)
Fan out
23 nets have fan out of 29
1 net with fan out of 28
Timing Analysis
Maximum frequency (@ 125C, VCCA = 2.25V, VCCI = 4.5V, Speed –1)
Array Clk => 72MHz
IO Clk => 71MHz
Hold time analysis (@ -55C, VCCA = 2.75V, VCCI = 5.5V, Speed –1)
Shortest path slack => 0.51ns
NASA design bounds user applications better than
Industry Tiger Team design
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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NASA Experiments
Test Protocol
RT54SX32S MEC
“Modified New Algo”
Parts to be tested in 500 hour steps
Stress levels increased for each step.
Voltage, # SSOs, amount of SSU, time
Internal circuit loading fixed at 120% of max load
Each step is 250 hours of HTOL followed by 250 hours of LTOL
HOT
300 parts
Project KH1
Temp = 125°C
VCCA= 2.75V
RTSX32SU UMC
300 parts
RT54SX32S MEC
“Modified New Algo”
250 hrs
Increasing VCCA/VCCI Voltage
Increasing SSO
Increasing SSU
Increased time
COLD
300 parts
Project KC1
Temp = -55°C
VCCA= 2.75V
RTSX32SU UMC
300 parts
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Increasing VCCA/VCCI Voltage
Increasing SSO
Increasing SSU
Increased time
250 hrs
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21
Appendix: RTSXS-U Test Data
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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ITT Design
Actel RTSX-SU (UMC) Data set
This data set includes the following for RTSXS-U:
2 sets of experiments were completed (P7, P4B2)
RTOL = Room Temperature Operating Life
TC = Temperature Cycle (-65°C to 150°C)
Industry Tiger Team Design - Summary
Product
Number of units
RTSX32S-U
366
RTSX72S-U
100
RTSX32S-U
198
Total
RTSX32S-U
RTSX72S-U
466
Total
136
Failures
0
0
68
68
0
Unit hours
104288
16800
33264
Type
RTOL
RTOL
RTOL
Expt
P7
P7
P4B2*
TC
TC
NA
NA
154352
0
0
6800
6800
13600
* These 198 Units completed 168 hours of P7 before being put into the P4B2 configuration
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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23
ITT Design
P7 Data
Configuration Details:
No I/O’s toggle, Array toggle rate = I/O toggle rate = 12.5%
3 monitor pins toggling - Visual readout using LED
Undershoot less than -0.4V
Industry Tiger Team Design - P7
Product
Number of units
RTSX32S-U
100
RTSX32S-U
266
RTSX72S-U
100
Total
Failures
0
0
0
466
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
#of hours
596
168
168
Unit hours
59600
44688
16800
Type
RTOL
RTOL
RTOL
121088
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ITT Design
P4B2 Data
Configuration Details:
I/O toggle rate = 50% (70 I/Os), Array toggle rate = 12.5%
~2V undershoot
Industry Tiger Team Design - P4B2
Product
Number of units
RTSX32S-U
198*
Total
Failures
0
#of hours
168
198
Unit hours
33264
Type
RTOL
33264
* These 198 Units completed 168 hours of P7 before being put into the P4B2 configuration
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
Paper #172
Wednesday, September 8th, 2004
25
NASA/Actel Team
NASA
Igor Kleyner
Rich Katz
Actel
Manish Babladi
Marco Cheung
Paul Louris
Minal Sawant
Dan Elftmann
MAPLD 2004: RTSX-S and RTSX-SU Reliability Test Vehicles
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Wednesday, September 8th, 2004
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