Datasheet

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  
SLAS491A − AUGUST 2005 − REVISED OCTOBER 2005
48
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted) (continued)
JTAG and Spy-Bi-Wire Interface
PARAMETER
TEST
CONDITIONS
VCC MIN TYP MAX UNIT
f
SBW
Spy-Bi-Wire input frequency 2.2 V / 3 V 0 20 MHz
t
SBW,Low
Spy-Bi-Wire low clock pulse length 2.2 V / 3 V 0.025 15 us
t
SBW,En
Spy-Bi-Wire enable time
(TEST high to acceptance of first clock edge, see
Note 1)
2.2 V/ 3 V 1 us
t
SBW,Ret
Spy-Bi-Wire return to normal operation time 2.2 V/ 3 V 15 100 us
f
TCK
TCK input frequency − 4-wire JTAG (see Note 2)
2.2 V 0 5 MHz
f
TCK
TCK input frequency − 4-wire JTAG (see Note 2)
3 V 0 10 MHz
R
Internal
Internal pull-down resistance on TEST 2.2 V/ 3 V 25 60 90 kΩ
NOTES: 1. Tools accessing the Spy-Bi-Wire interface need to wait for the maximum t
SBW,En
time after pulling the TEST/SBWCLK pin high
before appling the first SBWCLK clock edge.
2. f
TCK
may be restricted to meet the timing requirements of the module selected.
JTAG Fuse (see Note 1)
PARAMETER
TEST
CONDITIONS
VCC MIN TYP MAX UNIT
V
CC(FB)
Supply voltage during fuse-blow condition T
A
= 25°C 2.5 V
V
FB
Voltage level on TEST for fuse-blow 6 7 V
I
FB
Supply current into TEST during fuse blow 100 mA
t
FB
Time to blow fuse 1 ms
NOTES: 1. Once the fuse is blown, no further access to the JTAG/Test, Spy-Bi-Wire, and emulation feature is possible and JTAG is switched
to bypass mode.