Nexperia

74AHCT240

Octal buffer/line driver; inverting; 3-state

10. Dynamic characteristics

Table 7. Dynamic characteristics

Voltages are referenced to GND (ground = 0 V); for test circuit see Fig. 7.

25 °C

-40 °C to

+85 °C

-40 °C to

+125 °C

Symbol Parameter Conditions

Min Typ [1] Max

Min

Max

Min

Max

Unit

nAn to nYn; see Fig. 5

[2]

VCC = 4.5 V to 5.5 V; CL = 15 pF

-

3.0

5.8

1.0

6.8

1.0

8.5 ns

tpd

propagation

delay

VCC = 4.5 V to 5.5 V; CL = 50 pF

-

4.4

8.4

1.0

9.5

1.0

11.9 ns

nOE to nYn; see Fig. 6

[2]

VCC = 4.5 V to 5.5 V; CL = 15 pF

-

3.4

7.5

1.0

9.0

1.0

14.4 ns

ten

enable time

VCC = 4.5 V to 5.5 V; CL = 50 pF

-

4.5

9.5

1.0

11.5

1.0

14.4 ns

nOE to nYn; see Fig. 6

[2]

VCC = 4.5 V to 5.5 V; CL = 15 pF

-

3.9

6.1

1.0

6.7

1.0

8.3 ns

tdis

disable time

VCC = 4.5 V to 5.5 V; CL = 50 pF

-

6.2

8.7

1.0

9.2

1.0

11.5 ns

CPD

power

dissipation

capacitance

VI = GND to VCC; CL = 50 pF;

fi = 1 MHz

[3]

-

9

-

-

-

-

-

pF

[1] Typical values are measured at nominal supply voltage (VCC = 5.0 V).

[2] tpd is the same as tPLH and tPHL; ten is the same as tPZH and tPZL; tdis is the same as tPLZ and tPHZ.

[3] CPD is used to determine the dynamic power dissipation (PD in μW).

PD = CPD × VCC 2 × fi × N + Σ(CL × VCC 2 × fo) where:

fi = input frequency in MHz;

fo = output frequency in MHz;

CL = output load capacitance in pF;

VCC = supply voltage in V;

N = number of inputs switching;

Σ(CL × VCC 2 × fo) = sum of outputs.

74AHCT240

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© Nexperia B.V. 2020. All rights reserved

Product data sheet

Rev. 6 — 29 June 2020

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