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STRENGTH 5
88
I
77
OL
66
55
44
33
V
= 2.5V, +25°C
22
DD_IO
11
V
= 2.38V, +105°C
0
DD_IO
–11
V
= 2.5V, +25°C
DD_IO
–22
V
= 2.38V, +105°C
–33
DD_IO
–44
–55
–66
–77
–88
0
0.4
0.8
1.2
OUTPUT PIN VOLTAGE (V)
Figure 31. Typical Drive Currents at Strength 5
STRENGTH 6
100
90
I
80
OL
70
60
50
40
V
= 2.5V, +25°C
30
DD_IO
20
V
= 2.38V, +105°C
10
DD_IO
0
–10
V
= 2.5V, +25°C
–20
DD_IO
–30
V
= 2.38V, +105°C
–40
DD_IO
–50
–60
–70
–80
–90
–100
0
0.4
0.8
1.2
OUTPUT PIN VOLTAGE (V)
Figure 32. Typical Drive Currents at Strength 6
STRENGTH 7
110
100
I
90
OL
80
70
60
50
40
V
= 2.5V, +25°C
30
DD_IO
20
10
V
= 2.38V, +105°C
0
DD_IO
–10
V
= 2.5V, +25°C
–20
DD_IO
–30
–40
–50
V
= 2.38V, +105°C
DD_IO
–60
–70
–80
–90
–100
–110
0
0.4
0.8
1.2
OUTPUT PIN VOLTAGE (V)
Figure 33. Typical Drive Currents at Strength 7
V
= 2.63V, –40°C
DD_IO
V
= 2.63V, –40°C
DD_IO
I
OH
1.6
2.0
2.4
2.8
V
= 2.63V, –40°C
DD_IO
V
= 2.63V, –40°C
DD_IO
I
OH
1.6
2.0
2.4
2.8
V
= 2.63V, –40°C
DD_IO
V
= 2.63V, –40°C
DD_IO
I
OH
1.6
2.0
2.4
2.8
Rev. C | Page 37 of 48 | December 2006
TEST CONDITIONS
The ac signal specifications (timing parameters) appear in
Table 29 on Page
28. These include output disable time, output
enable time, and capacitive loading. The timing specifications
for the DSP apply for the voltage reference levels in
INPUT
OR
1.25V
OUTPUT
Figure 34. Voltage Reference Levels for AC Measurements
(Except Output Enable/Disable)
Output Disable Time
Output pins are considered to be disabled when they stop driv-
ing, go into a high impedance state, and start to decay from their
output high or low voltage. The time for the voltage on the bus
to decay by ΔV is dependent on the capacitive load, C
load current, I
. This decay time can be approximated by the fol-
L
lowing equation:
t
DECAY
The output disable time t
DIS
t
and t
as shown in
MEASURED_DIS
DECAY
t
is the interval from when the reference signal
MEASURED_DIS
switches to when the output voltage decays ΔV from the mea-
sured output high or output low voltage. t
, and with ΔV equal to 0.4 V.
with test loads C
and I
L
L
REFERENCE
SIGNAL
t
MEASURED_DIS
t
DIS
V
OH (MEASURED)
V
OL (MEASURED)
OUTPUT STOPS
DRIVING
VOLTAGE TO BE APPROXIMATELY 1.25V.
Figure 35. Output Enable/Disable
ADSP-TS201S
Figure
1.25V
and the
L
(
Δ
) I
⁄
C
V
=
L
L
is the difference between
Figure
35. The time
is calculated
DECAY
t
MEASURED_ENA
t
ENA
V
– V
1.65V
OH (MEASURED)
V
+ V
0.85V
OL (MEASURED)
t
t
DECAY
RAMP
OUTPUT STARTS
DRIVING
HIGH IMPEDANCE STATE.
TEST CONDITIONS CAUSE THIS
34.
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