9 Threads found on edaboard.com: Negedge Dft
How to stitch a couple of negedge flops in the design where most of the flops are posedge?
How to balance chains where only few flops are negedge but most flops are posedge?
Is it possible to combine posedge and negedge flops in the same chain?
ASIC Design Methodologies and Tools (Digital) :: 06-27-2015 10:46 :: ivlsi :: Replies: 4 :: Views: 642
I am working on scan insertion. I have some querries on the same.
My understanding is lockup latch is not needed when we have negedge flop followed by pos edge flop. But when we have pos edge flop followed by neg edge flop, can I use lockup latch between pos edge -> lockup latch -> neg edge ? Will this work ?
or lockup latches are used on
ASIC Design Methodologies and Tools (Digital) :: 10-17-2013 06:17 :: abc_81 :: Replies: 4 :: Views: 557
i have selected the scan style as -clocked scan in dft compiler, instead of mux based design
my flip-flop module is as below,
The above code fails in the compile -scan with the error "No SCAN equivalent Found"
ASIC Design Methodologies and Tools (Digital) :: 01-23-2012 04:44 :: vaishna :: Replies: 0 :: Views: 667
Hi, you define scan clock to be clk_i. Does clk_i drive the clock pins of your flops directly? Or is there some gating function that enables clk?
I this RTL verilog is very simple as below,
ASIC Design Methodologies and Tools (Digital) :: 11-17-2010 00:34 :: charles_hoho :: Replies: 9 :: Views: 4283
You'd better not to use registers with different clock edges. Instead, you should generated a inverted clocks before the negedge register and then this register will be implementation into a posedge register.
ASIC Design Methodologies and Tools (Digital) :: 10-13-2010 02:36 :: Creese :: Replies: 5 :: Views: 6118
In one design, there are both posedge and negedge FFs. for the dft design, if i want to put all the negedge FFs at the begining of the scan chain, how can i make the constrain in the script?
ASIC Design Methodologies and Tools (Digital) :: 12-03-2007 22:24 :: zjwang :: Replies: 3 :: Views: 1147
Synopsys document said,
For edge-sensitive scan shift style in mixed phases design( posedge and negedge sensitive register co-existing),
" for a positive pulse, the rising-edge-triggered filp-flop must be clocked first; for a negative pulse, the rising-edge-triggered flip-flop must be clocked first."
Why should this rule be met? And what
ASIC Design Methodologies and Tools (Digital) :: 08-19-2005 02:03 :: qjlsy :: Replies: 5 :: Views: 1474
The clock is not always on. Just give the posedge or negedge of the clock in some conditions. I know they will emply functional pattern, or BIST to running test.
Another, how to do dft IN FPGA chip. Before vendor shipping the chip, chip test should be done. We can make scan chain in FPGA? I don't think so.
I want to know detail about this.
ASIC Design Methodologies and Tools (Digital) :: 04-14-2005 08:39 :: FLEXcertifydll :: Replies: 2 :: Views: 806
I have generated a dft ready gate_level netlist, with TestMode connected to "Dummy 0 Clip Cell". When TestMode = 1, the negedge clocked F.F. is changed to posedge clocked F.F., a clock mux is used.
When I analysis timing, PrimeTime knows the F.F. is negedge, but DesignCompiler does not know it, and I must do set_case_analysis to get (...)
ASIC Design Methodologies and Tools (Digital) :: 03-06-2005 02:11 :: seanwu :: Replies: 0 :: Views: 912