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74HC_HCT240_15 Datasheet, PDF (8/18 Pages) NXP Semiconductors – Octal buffer/line driver; 3-state; inverting
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NXP Semiconductors
74HC240; 74HCT240
Octal buffer/line driver; 3-state; inverting
Table 7. Dynamic characteristics …continued
GND = 0 V; for load circuit see Figure 8.
Symbol Parameter
Conditions
Min
74HCT240
tpd
propagation delay nAn to nYn;
see Figure 6
VCC = 4.5 V
VCC = 5.0 V; CL = 15 pF
ten
enable time
nOE to nYn; VCC = 4.5 V; see
Figure 7
tdis
disable time
nOE to nYn; VCC = 4.5 V; see
Figure 7
tt
transition time
VCC = 4.5 V; see Figure 6
CPD
power dissipation per transceiver;
capacitance
VI = GND to VCC − 1.5 V
[1]
-
-
[2]
-
[3]
-
[4]
-
[5]
-
[1] tpd is the same as tPHL and tPLH.
[2] ten is the same as tPZH and tPZL.
[3] tdis is the same as tPHZ and tPLZ.
[4] tt is the same as tTHL and tTLH.
[5] CPD is used to determine the dynamic power dissipation (PD in µW):
PD = CPD × VCC2 × fi × N + ∑ (CL × VCC2 × 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;
∑ (CL × VCC2 × fo) = sum of outputs.
25 °C
Typ
11
9
13
13
5
30
−40 °C to +125 °C Unit
Max Max
Max
(85 °C) (125 °C)
20
25
-
-
30
38
25
31
12
15
-
-
30 ns
- ns
45 ns
38 ns
18 ns
- pF
11. Waveforms
VI
nAn input
GND
VOH
nYn output
VOL
VM
tPHL
VM
VM
tPLH
VM
mgu781
Measurement points are given in Table 8.
VOL and VOH are typical voltage output drop that occur with the output load.
Fig 6. Input (nAn) to output (nYn) propagation delays and output transition times
74HC_HCT240_3
Product data sheet
Rev. 03 — 2 August 2007
© NXP B.V. 2007. All rights reserved.
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