INDUSTRIAL TEMPERATURE RANGE
4
IDT74FCT521AT/CT
FAST CMOS 8-BIT IDENTITY COMPARATOR
Symbol Parameter Test Conditions
(1)
Min. Typ.
(2)
Max. Unit
ΔI
CC Quiescent Power Supply Current VCC = Max. — 0.5 2 mA
TTL Inputs HIGH VIN = 3.4V
(3)
ICCD Dynamic Power Supply VCC = Max. VIN = VCC — 0.15 0.25 mA/
Current
(4)
Outputs Open VIN = GND MHz
One Input Toggling
50% Duty Cycle
I
C Total Power Supply Current
(6)
VCC = Max. VIN = VCC — 1.5 3.5 mA
Outputs Open VIN = GND
fi = 10MHz VIN = 3.4V — 1.8 4.5
One Bit Toggling V
IN = GND
50% Duty Cycle
NOTES:
1. For conditions shown as Min. or Max., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC = 5.0V, +25°C ambient.
3. Per TTL driven input; (V
IN = 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 ΔICC 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 Input Transition Pair (HLH or LHL)
fCP = Clock Frequency for Register Devices (Zero for Non-Register Devices)
fi = Output Frequency
Ni = Number of Outputs at fi
All currents are in milliamps and all frequencies are in megahertz.
POWER SUPPLY CHARACTERISTICS
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
74FCT521AT 74FCT521CT
Symbol Parameter Condition
(1)
Min.
(2)
Max. Min.
(2)
Max. Unit
tPLH Propagation Delay CL = 50pF 1.5 7.2 1.5 4.5 ns
tPHL Ax or Bx to OA = B RL = 500Ω
tPLH Propagation Delay 1.5 6 1.5 4.1 ns
tPHL IA = B to OA = B
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
