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CY7C1381DV25, CY7C1381FV25
CY7C1383DV25, CY7C1383FV25
Document #: 38-05547 Rev. *E Page 13 of 28
the TAP controller, it will directly control the state of the output
(Q-bus) pins, when the EXTEST is entered as the current
instruction. When HIGH, it will enable the output buffers to
drive the output bus. When LOW, this bit will place the output
bus into a High-Z condition.
This bit can be set by entering the SAMPLE/PRELOAD or
EXTEST command, and then shifting the desired bit into that
cell, during the Shift-DR state. During Update-DR, the value
loaded into that shift-register cell will latch into the preload
register. When the EXTEST instruction is entered, this bit will
directly control the output Q-bus pins. Note that this bit is
preset HIGH to enable the output when the device is powered
up, and also when the TAP controller is in the Test-Logic-Reset
state.
Reserved
These instructions are not implemented but are reserved for
future use. Do not use these instructions.
TAP Timing
TAP AC Switching Characteristics
Over the Operating Range
[10, 11]
Parameter Description Min. Max. Unit
Clock
t
TCYC
TCK Clock Cycle Time 50 ns
t
TF
TCK Clock Frequency 20 MHz
t
TH
TCK Clock HIGH time 20 ns
t
TL
TCK Clock LOW time 20 ns
Output Times
t
TDOV
TCK Clock LOW to TDO Valid 10 ns
t
TDOX
TCK Clock LOW to TDO Invalid 0 ns
Setup Times
t
TMSS
TMS Setup to TCK Clock Rise 5 ns
t
TDIS
TDI Setup to TCK Clock Rise 5 ns
t
CS
Capture Setup to TCK Rise 5 ns
Hold Times
t
TMSH
TMS Hold after TCK Clock Rise 5 ns
t
TDIH
TDI Hold after Clock Rise 5 ns
t
CH
Capture Hold after Clock Rise 5 ns
t
TL
Test Clock
(TCK)
123456
Test Mode Select
(TMS)
t
TH
Test Data-Out
(TDO)
t
CYC
Test Data-In
(TDI)
t
TMSH
t
TMSS
t
TDIH
t
TDIS
t
TDOX
t
TDOV
DON’T CARE UNDEFINED
Notes
10.t
CS
and t
CH
refer to the setup and hold time requirements of latching data from the boundary scan register.
11. Test conditions are specified using the load in TAP AC test conditions. t
R
/t
F
= 1 ns.
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