adsp-21266skstz-2b Analog Devices, Inc., adsp-21266skstz-2b Datasheet - Page 39

• Manufacturer Part Number: adsp-21266skstz-2b
• Description: Sharc Embedded Processor
• Manufacturer: Analog Devices, Inc.

OUTPUT DRIVE CURRENTS
Figure 28
ers of the ADSP-2126x. The curves represent the current drive
capability of the output drivers as a function of output voltage.
TEST CONDITIONS
The ac signal specifications (timing parameters) appear in
Table 16 on Page 20
output disable time, output enable time, and capacitive loading.
Timing is measured on signals when they cross the 1.5 V level as
described in
sured between the point that the first signal reaches 1.5 V and
the point that the second signal reaches 1.5 V.
OUTPUT
–20
–30
–40
–10
PIN
Figure 29. Equivalent Device Loading for AC Measurements
40
30
20
10
TO
OUTPUT
Figure 30. Voltage Reference Levels for AC Measurements
0
INPUT
0
shows typical I-V characteristics for the output driv­
OR
Figure
V OL
0.5
1.5V
30. All delays (in nanoseconds) are mea­
3.47V, –45°C
SWEEP (V DDEXT ) VOLTAGE (V)
through
Figure 28. Typical Drive
1
(Includes All Fixtures)
3.11V, 125°C
30pF
1.5
Table 37 on Page
V OH
2
3.11V, 125°C
50�
2.5
3.3V, 25°C
3
38. These include
3.3V, 25°C
3.47V, –45°C
1.5V
3.5
Rev. E | Page 39 of 48 | July 2008
1.5V
CAPACITIVE LOADING
Output delays and holds are based on standard capacitive loads:
30 pF on all pins (see
how output delays and holds vary with load capacitance (note
that this graph or derating does not apply to output disable
delays). The graphs of
not be linear outside the ranges shown for Typical Output Delay
vs. Load Capacitance and Typical Output Rise Time (20% to
80%, V = Min) vs. Load Capacitance.
ADSP-21261/ADSP-21262/ADSP-21266
12
10
0
8
6
4
2
12
10
8
6
4
2
0
0
0
Figure 32. Typical Output Rise/Fall Time
Figure 31. Typical Output Rise Time
y = 0.0467x + 1.6323
50
y = 0.049x + 1.5105
(20% to 80%, V
(20% to 80%, V
50
Figure
Figure
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
29).
100
31,
100
y = 0.0482x + 1.4604
y = 0.045x + 1.524
Figure 32
Figure
DDEXT
DDEXT
= Max)
= Min)
RIS
150
150
32, and
RISE
E
shows graphically
FALL
FALL
Figure 33
200
200
250
may
250