![](/html/Motorola/902948/page4.png)
MC74HCT240A
INPUT
A OR B
tPHL
OUTPUT
YA OR YB
tTHL
tr
2.7 V
1.3 V
0.3 V
90%
1.3 V
10%
Figure 1.
SWITCHING WAVEFORMS
tf
3V
GND
tPLH
tTLH
ENABLE
A OR B
OUTPUT Y
OUTPUT Y
1.3 V
tPZL tPLZ
1.3 V
tPZH tPHZ
1.3 V
Figure 2.
3V
GND
HIGH
IMPEDANCE
10% VOL
90% VOH
HIGH
IMPEDANCE
DEVICE
UNDER
TEST
TEST POINT
OUTPUT
CL*
DEVICE
UNDER
TEST
TEST POINT
OUTPUT
1 kΩ
CL*
CONNECT TO VCC WHEN
TESTING tPLZ AND tPZL.
CONNECT TO GND WHEN
TESTING tPHZ AND tPZH.
* Includes all probe and jig capacitance
Figure 3. Test Circuit
LOGIC DETAIL
TO THREE OTHER
A OR B INVERTERS
* Includes all probe and jig capacitance
Figure 4. Test Circuit
INPUT
A OR B
ONE OF 8
INVERTERS
VCC
YA
OR
YB
OUTPUT ENABLES
ENABLE A OR ENABLE B
MOTOROLA
4
High–Speed CMOS Logic Data
DL129 — Rev 6