CD74HC540 Datasheet, PDF (7/8 Pages) Texas Instruments – High Speed CMOS Logic Octal Buffer and Line Drivers, Three-State

Test Circuits and Waveforms (Continued)
OTHER
INPUTS
TIED HIGH
OR LOW
OUTPUT
DISABLE
IC WITH
THREE-
STATE
OUTPUT
OUTPUT
R_L = 1kΩ
C_L
50pF
V_CC FOR t_PLZ AND t_PZL
GND FOR t_PHZ AND t_PZH
NOTE: Open drain waveforms t_PLZ and t_PZL are the same as those for three-state shown on the left. The test circuit is Output R_L = 1kΩ to
V_CC, C_L = 50pF.
FIGURE 5. HC AND HCT THREE-STATE PROPAGATION DELAY TEST CIRCUIT
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