Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

74ACTQ16244 Datasheet(PDF) 5 Page - Fairchild Semiconductor

Part No. 74ACTQ16244
Description  16-Bit Buffer/Line Driver with 3-STATE Outputs
Download  7 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  FAIRCHILD [Fairchild Semiconductor]
Homepage  http://www.fairchildsemi.com
Logo 

74ACTQ16244 Datasheet(HTML) 5 Page - Fairchild Semiconductor

   
Zoom Inzoom in Zoom Outzoom out
 5 / 7 page
background image
5
www.fairchildsemi.com
FACT Noise Characteristics
The setup of a noise characteristics measurement is critical
to the accuracy and repeatability of the tests. The following
is a brief description of the setup used to measure the
noise characteristics of FACT.
Equipment:
Hewlett Packard Model 8180A Word Generator
PC-163A Test Fixture
Tektronics Model 7854 Oscilloscope
Procedure:
1. Verify Test Fixture Loading: Standard Load 50 pF,
500
:.
2. Deskew the HFS generator so that no two channels
have greater than 150 ps skew between them. This
requires that the oscilloscope be deskewed first. It is
important to deskew the HFS generator channels
before testing. This will ensure that the outputs switch
simultaneously.
3. Terminate all inputs and outputs to ensure proper load-
ing of the outputs and that the input levels are at the
correct voltage.
4. Set the HFS generator to toggle all but one output at a
frequency of 1 MHz. Greater frequencies will increase
DUT heating and affect the results of the measure-
ment.
VOHV and VOLP are measured with respect to ground reference.
Input pulses have the following characteristics: f
1MHz, tr
3ns,
tf
3 ns, skew
 150 ps.
FIGURE 1. Quiet Output Noise Voltage Waveforms
5. Set the HFS generator input levels at 0V LOW and 3V
HIGH for ACT devices and 0V LOW and 5V HIGH for
AC devices. Verify levels with an oscilloscope.
VOLP/VOLV and VOHP/VOHV:
• Determine the quiet output pin that demonstrates the
greatest noise levels. The worst case pin will usually be
the furthest from the ground pin. Monitor the output volt-
ages using a 50
: coaxial cable plugged into a standard
SMB type connector on the test fixture. Do not use an
active FET probe.
• Measure VOLP and VOLV on the quiet output during the
worst case transition for active and enable. Measure
VOHP and VOHV on the quiet output during the worst
case active and enable transition.
• Verify that the GND reference recorded on the oscillo-
scope has not drifted to ensure the accuracy and repeat-
ability of the measurements.
VILD and VIHD:
• Monitor one of the switching outputs using a 50
: coaxial
cable plugged into a standard SMB type connector on
the test fixture. Do not use an active FET probe.
• First increase the input LOW voltage level, VIL, until the
output begins to oscillate or steps out a min of 2 ns.
Oscillation is defined as noise on the output LOW level
that exceeds VIL limits, or on output HIGH levels that
exceed VIH limits. The input LOW voltage level at which
oscillation occurs is defined as VILD.
• Next decrease the input HIGH voltage level, VIH, until
the output begins to oscillate or steps out a min of 2 ns.
Oscillation is defined as noise on the output LOW level
that exceeds VIL limits, or on output HIGH levels that
exceed VIH limits. The input HIGH voltage level at which
oscillation occurs is defined as VIHD.
• Verify that the GND reference recorded on the oscillo-
scope has not drifted to ensure the accuracy and repeat-
ability of the measurements
FIGURE 2. Simultaneous Switching Test Circuit


Html Pages

1  2  3  4  5  6  7 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn