CD74AC251 Datasheet, PDF (6/8 Pages) Texas Instruments – 8-Input Multiplexer, Three-State

CD74AC251, CD74ACT251
Switching Specifications Input t_r, t_f = 3ns, C_L = 50pF (Worst Case) (Continued)
-40^oC TO 85^oC
-55^oC TO 125^oC
PARAMETER
Three-State Output
Capacitance
SYMBOL
V_CC (V)
MIN
C_O
TYP
MAX
MIN
TYP
MAX
Input Capacitance
C_I
-
Power Dissipation Capacitance
C_PD
-
(Note 11)
-
-
10
-
-
10
-
45
-
-
45
-
NOTES:
8. Limits tested 100%.
9. 3.3V Min is at 3.6V, Max is at 3V.
10. 5V Min is at 5.5V, Max is at 4.5V.
11. C_PD is used to determine the dynamic power consumption per device.
P_D = V_CC2 f_i (C_PD + C_L) where f_i = input frequency, C_L = output load capacitance, V_CC = supply voltage.
UNITS
pF
pF
t_r = 3ns
OUTPUT
DISABLE
t_PLZ
t_f = 3ns
t_PZL
INPUT LEVEL
90%
V_S
10%
GND
OUTPUT: LOW
TO OFF TO LOW
OUTPUT: HIGH
TO OFF TO HIGH
t_PHZ
OUTPUTS
ENABLED
OTHER
INPUTS
(TIED HIGH
OR LOW)
OUTPUT
DISABLE
DUT
WITH
THREE-
STATE
OUTPUT
t_PZH
V_S
0.2V_{CC VOL (≠ GND)}
0.8 V_CC^{VOH (≠ VCC)}
V_S
OUTPUTS
OUTPUTS
DISABLED
ENABLED
GND (t_PHZ, t_PZH)
OPEN (t_PHL, t_PLH)
500Ω†
R_L
2 V_CC (t_PLZ, t_PZL)
(OPEN DRAIN)
C_L
50pF
OUT
500Ω†
R_L
†FOR AC SERIES ONLY: WHEN V_CC = 1.5V, R_L = 1kΩ
FIGURE 1. THREE-STATE PROPAGATION DELAY WAVEFORMS AND TEST CIRCUIT
t_r = 3ns
I_N
90%
V_S
10%
t_f = 3ns
INPUT LEVEL
INVERTING
OUTPUT Y
t_PHL
NON-INVERTING
OUTPUT Y
t_PLH
V_S
t_PLH
V_S
t_PHL
FIGURE 2. PROPAGATION DELAY TIMES
6