Datasheet

 
    
SLCS115E − DECEMBER 1986 − REVISED JULY 2003
9
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251−1443
PARAMETER MEASUREMENT INFORMATION
Propagation delay time is defined as the interval between the application of an input step function and the instant
when the output reaches 50% of its maximum value. Propagation delay time, low-to-high-level output, is
measured from the leading edge of the input pulse, while propagation delay time, high-to-low-level output, is
measured from the trailing edge of the input pulse. Propagation delay time measurement at low input signal
levels can be greatly affected by the input offset voltage. The offset voltage should be balanced by the
adjustment at the inverting input (as shown in Figure 3) so that the circuit is just at the transition point. Then a
low signal, for example, 105 mV or 5 mV overdrive, causes the output to change state.
DUT
V
DD
C
L
(see Note A)
Pulse
Generator
10 Ω
10 Turn
1 V
− 1 V
1 kΩ
50 Ω
1 µF
0.1 µF
TEST CIRCUIT
100 mV
Input
Overdrive
50%
t
PLH
100 mVInput
Overdrive
90%
50%
10%
t
f
t
PHL
Low-to-High-
Level Output
High-to-Low-
Level Output
VOLTAGE WAVEFORMS
5.1 kΩ
Input Offset Voltage
Compensation
Adjustment
90%
t
r
10%
NOTE A: C
L
includes probe and jig capacitance.
Figure 3. Propagation Delay, Rise Time, and Fall Time Circuit and Voltage Waveforms