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INDUSTRIALTEMPERATURERANGE
4
IDT74FCT621T/AT
FASTCMOSOCTALBUSTRANSCEIVER(OPENDRAIN)
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
IDT74FCT621T
IDT74FCT621AT
Symbol
Parameter
Condition(1)
Min.(2)
Max.
Min.(2)
Max.
Unit
tPLH
Propagation Delay, A to B
CL = 50pF
5.5
13
5.5
12
ns
tPHL
RL = 500
Ω
1.5
8.5
1.5
6.8
tPLH
Propagation Delay, B to A
5.5
12.5
5.5
12
ns
tPHL
1.5
8
1.5
6.4
tPLH
Propagation Delay,
GBA to A
5.5
14
5.5
13
ns
tPHL
1.5
8.5
1.5
6.8
tPLH
Propagation Delay,
GAB to B
5.5
14
5.5
13
ns
tPHL
1.5
8
1.5
6.4
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
Test Conditions(1)
Min.
Typ.(2)
Max.
Unit
ΔICC
Quiescent Power Supply Current
VCC = Max.
—
0.5
2
mA
TTL Inputs HIGH
VIN = 3.4V
(3)
ICCD
Dynamic Power Supply Current
(4)
Vcc = Max.
VIN = VCC
—
0.15
0.25
mA/MHz
OutputsOpen
VIN = GND
GBA = GAB = GND or VCC
OneInputToggling
50% Duty Cycle
IC
Total Power Supply Current
(6,7)
Vcc = Max.
VIN = VCC
—
1.5
3.5
mA
OutputsOpen
VIN = GND
GBA = GAB = GND or VCC
One Bit Toggling
VIN = 3.4V
—
1.8
4.5
at fi =10MHz
VIN = GND
50% Duty Cycle
Vcc = Max.
VIN = VCC
—3
6
(5)
OutputsOpen
VIN = GND
GBA = GAB = GND or VCC
EightBitsToggling
VIN = 3.4V
—
5
14
(5)
at fi = 2.5MHz
VIN = GND
50% Duty Cycle
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at VCC = 5.0V, +25°C ambient.
3. Per TTL driven input (VIN = 3.4V); all other inputs at VCC or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. Values for these conditions are examples of the ICC formula. These limits are guaranteed but not tested.
6. IC = IQUIESCENT + IINPUTS + IDYNAMIC
IC = ICC +
ΔICC DHNT + ICCD (fCP/2 + fiNi)
ICC = Quiescent Current
ΔICC = Power Supply Current for a TTL High Input (VIN = 3.4V)
DH = Duty Cycle for TTL Inputs High
NT = Number of TTL Inputs at DH
ICCD = Dynamic Current Caused by an Output Transition Pair (HLH or LHL)
fCP = Clock Frequency for Register Devices (Zero for Non-Register Devices)
fi = Input Frequency
Ni = Number of Inputs at fi
All currents are in milliamps and all frequencies are in megahertz.
7. This test is performed with outputs tied to GND through a pull-down resistor.