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Introduction
1.6 Design for Test (DFT) Methodology
Samsung ASIC
1-21
STD130
1.6
Design for Test (DFT)
Methodology
Samsung’s libraries are designed with DFT in mind. Samsung’s DFT
methodology includes the ability to include full or partial scan path testing,
boundary-scan JTAG for board level testing, Memory BIST, and analog testing.
A brief description of the features of Samsung’s scan, BIST, and JTAG as well as
a more detailed discussion of boundary scan architecture follows.
1.6.1 SCAN DESIGN
Multiplexed scan flip-flops that minimize area and delay overhead needed to
implement scan design.
Automated design rule checking, scan insertion, and test pattern generation
High fault coverage on synchronous designs
1.6.2 BIST (BUILT-IN SELF-TEST)
Efficient test solution for compiled memory macrocells
At speed and parallel testing of multiple memories
Combination with internal scan design and core testing
1.6.3 BOUNDARY SCAN
IEEE Std 1149.1
JTAG boundary scan registers implemented with primitive cells
Boundary Scan Description Language (BSDL) for board testing
May be combed with internal scan design and core testing
JTAG Boundary Scan Architecture
Boundary scan architecture contains a TAP (Test Access Port), a TAP controller,
an instruction register, and a group of test data registers. The instruction and test
data registers are separate shift-register-based paths connected in parallel with
a common serial data input and a common serial data output. The common serial
data input and output are connected to the TAP, TDI and TDO signals. The TAP
controller selects the alternative instruction and test data register paths between
TDI and TDO. A schematic view of the top level design of the JTAG test logic
architecture is shown in the Figure 1-14.