P4C150
AC TEST CONDITIONS
Input Pulse Levels
GND to 3.0V
Input Rise and Fall Times
3ns
Input Timing Reference Level
1.5V
Output Timing Reference Level
1.5V
Output Load
See Figures 1 and 2
TRUTH TABLE
Mode
RS CS OE WE Output
Not Selected
X H X X High Z
RESET
L L X H High Z
Output Disabled H L H H High Z
READ
WRITE
H LL H
D
OUT
H L X L High Z
D OUT
255Ω
+5
480Ω
300pF(5pF* for tHZ, tLZ, tOHZ,
tOLZ, tWZ and tOW)
DOUT
R TH = 166.5 Ω
VTH = 1.73 V
30pF(5pF* for tHZ, tLZ, tOHZ,
tOLZ, tWZ and tOW )
Figure 1. Output Load
* including scope and test fixture.
Figure 2. Thevenin Equivalent
Note:
Due to the ultra-high speed of the P4C150, care must be taken when
testing this device; an inadequate setup can cause a normal functioning
part to be rejected as faulty. Long high-inductance leads that cause
supply bounce must be avoided by bringing the VCC and ground planes
directly up to the contactor fingers. A 0.01 µF high frequency capacitor
is also required between VCC and ground. To avoid signal reflections,
proper termination must be used; for example, a 50Ω test environment
should be terminated into a 50Ω load with 1.73V (Thevenin Voltage) at
the comparator input, and a 116Ω resistor must be used in series with
DOUT to match 166Ω (Thevenin Resistance).
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