3

INDUSTRIALTEMPERATURERANGE

IDT74FST6800

10-BIT BUS SWITCH WITH PRECHARGED OUTPUTS

Symbol

Parameter

Test Conditions(1)

Min.

Typ.(2)

Max.

Unit

ΔICC

Quiescent Power Supply Current

VCC = Max.

—

0.5

1.5

mA

TTL Inputs HIGH

VIN = 3.4V(3)

ICCD

Dynamic Power Supply

VCC = Max., Outputs Open

VIN = VCC

—30

40

μA/

Current(4)

Enable Pin Toggling

VIN = GND

MHz/

50% Duty Cycle

Enable

IC

Total Power Supply Current(6)

VCC = Max., Outputs Open

VIN = VCC

—3

4

mA

Enable Pin Toggling

VIN = GND

(Ten Switches Toggling)

fi = 10MHz

VIN = 3.4V

—

3.3

4.8

50% Duty Cycle

VIN = GND

POWER SUPPLY CHARACTERISTICS

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 Icc formula. These limits are guaranteed but not tested.

6. IC = IQUIESCENT + IINPUTS + IDYNAMIC

IC = ICC +

ΔICC DHNT + ICCD (fiN)

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 = Input Frequency

N = Number of SwitchesToggling at fi

All currents are in milliamps and all frequencies are in megahertz

SWITCHING CHARACTERISTICS OVER OPERATING RANGE

FollowingConditionsApplyUnlessOtherwiseSpecified:

Industrial: TA = -40°C to +85°C, VCC = 5.0V ± 5%

Symbol

Description

Condition(1)

Min.(2)

Typ.

Max.

Unit

tPLH

DataPropagationDelay

CL = 50pF

—

—

0.25

ns

tPHL

Ax, Bx to Bx, Ax(3,4)

RL = 500

Ω

tPZH

Switch Turn On Delay

1.5

—

6.5

ns

tPZL

ON to Ax, Bx

tPHZ

Switch Turn Off Delay

1.5

—

5.5

ns

tPLZ

ON to Ax, Bx(3)

NOTES:

1. See test circuit and waveforms.

2. Minimum limits guaranteed but not tested.

3. This parameter is guaranteed by design but not tested.

4. The bus switch contributes no propagation delay other than the RC delay of the on resistance of the switch and the load capacitance. The time constant for the switch alone

is of the order of 0.25 ns for 50 pF load. Since this time is constant and much smaller than the rise/fall times of typical driving signals, it adds very little propagation delay to the

system. Propagation delay of the bus switch when used in a system is determined by the driving circuit on the driving side of the switch and its interaction with the load on

the driven side.