Datasheet

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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.
90%
Pulse
Generator
V
DD
DUT
TEST CIRCUIT
Input Offset Voltage
Compensation Adjustment
Low-to-High-Level
Output
VOLTAGE WAVEFORMS
High-to-Low-Level
Output
1 µF
5.1 kΩ
50 Ω
1 kΩ
1 V
−1 V
10 Ω
10 Turn
0.1 µF
C
L
(see Note A)
Overdrive
Input
Overdrive
Input
100 mV
100 mV
50%
50%
10%
t
PLH
t
PHL
t
THL
NOTE A: C
L
includes probe and jig capacitance.
Figure 3. Propagation Delay, Rise, and Fall Times Test Circuit and Voltage Waveforms