PDF《74AHC245; 74AHCT245》

L = LOW voltage level;

X = don'

t care;

Z = high-impedance OFF-state. 7. Limiting values [1] The input and output voltage ratings may be exceeded if the input and output current ratings are observed. [2] For SO20 packages: above

70 °C the value of Ptot derates linearly at

8 mW/K. For TSSOP20 packages: above

60 °C the value of Ptot derates linearly at 5.5 mW/K. For DHVQFN20 packages: above

60 °C the value of Ptot derates linearly at 4.5 mW/K. B1

17 data input/output B0

18 data input/output OE

19 output enable input (active LOW) VCC

20 supply voltage Table 2. Pin description …continued Symbol Pin Description Table 3. Function table[1] Control Input/output OE DIR An Bn L L A = B inputs L H inputs B = A H X Z Z Table 4. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground =

0 V). Symbol Parameter Conditions Min Max Unit VCC supply voltage ?0.5 +7.0 V VI input voltage ?0.5 +7.0 V IIK input clamping current VI <

?0.5 V [1] ?20 - mA IOK output clamping current VO <

?0.5 V or VO >

VCC + 0.5 V [1] ?20 +20 mA IO output current VO = ?0.5 V to (VCC + 0.5 V) ?25 +25 mA ICC supply current - +75 mA IGND ground current ?75 - mA Tstg storage temperature ?65 +150 °C Ptot total power dissipation Tamb = ?40 °C to +125 °C [2] -

500 mW 74AHC_AHCT245_5 ? NXP B.V. 2009. All rights reserved. Product data sheet Rev.

05 ―

28 April

2009 5 of

16 NXP Semiconductors 74AHC245;

74AHCT245 Octal bus transceiver;

3-state 8. Recommended operating conditions 9. Static characteristics Table 5. Operating conditions Symbol Parameter Conditions Min Typ Max Unit 74AHC245 VCC supply voltage 2.0 5.0 5.5 V VI input voltage

0 - 5.5 V VO output voltage

0 - VCC V Tamb ambient temperature ?40 +25 +125 °C ?t/?V input transition rise and fall rate VCC = 3.0 V to 3.6 V - -

100 ns/V VCC = 4.5 V to 5.5 V - -

20 ns/V 74AHCT245 VCC supply voltage 4.5 5.0 5.5 V VI input voltage

0 - 5.5 V VO output voltage

0 - VCC V Tamb ambient temperature ?40 +25 +125 °C ?t/?V input transition rise and fall rate VCC = 4.5 V to 5.5 V - -

20 ns/V Table 6. Static characteristics At recommended operating conditions;

voltages are referenced to GND (ground =

0 V). Symbol Parameter Conditions

25 °C ?40 °C to +85 °C ?40 °C to +125 °C Unit Min Typ Max Min Max Min Max 74AHC245 VIH HIGH-level input voltage VCC = 2.0 V 1.5 - - 1.5 - 1.5 - V VCC = 3.0 V 2.1 - - 2.1 - 2.1 - V VCC = 5.5 V 3.85 - - 3.85 - 3.85 - V VIL LOW-level input voltage VCC = 2.0 V - - 0.5 - 0.5 - 0.5 V VCC = 3.0 V - - 0.9 - 0.9 - 0.9 V VCC = 5.5 V - - 1.65 - 1.65 - 1.65 V VOH HIGH-level output voltage VI = VIH or VIL IO = ?50 ?A;

VCC = 2.0 V 1.9 2.0 - 1.9 - 1.9 - V IO = ?50 ?A;

VCC = 3.0 V 2.9 3.0 - 2.9 - 2.9 - V IO = ?50 ?A;

VCC = 4.5 V 4.4 4.5 - 4.4 - 4.4 - V IO = ?4.0 mA;

VCC = 3.0 V 2.58 - - 2.48 - 2.40 - V IO = ?8.0 mA;

VCC = 4.5 V 3.94 - - 3.80 - 3.70 - V VOL LOW-level output voltage VI = VIH or VIL IO =

50 ?A;

VCC = 2.0 V -

0 0.1 - 0.1 - 0.1 V IO =

50 ?A;

VCC = 3.0 V -

0 0.1 - 0.1 - 0.1 V IO =

50 ?A;

VCC = 4.5 V -

0 0.1 - 0.1 - 0.1 V IO = 4.0 mA;

VCC = 3.0 V - - 0.36 - 0.44 - 0.55 V IO = 8.0 mA;

VCC = 4.5 V - - 0.36 - 0.44 - 0.55 V 74AHC_AHCT245_5 ? NXP B.V. 2009. All rights reserved. Product data sheet Rev.

05 ―

28 April

2009 6 of

16 NXP Semiconductors 74AHC245;

74AHCT245 Octal bus transceiver;

3-state II input leakage current VI = 5.5 V or GND;

VCC =

0 V to 5.5 V - - 0.1 - 1.0 - 2.0 ?A IOZ OFF-state output current VI = VIH or VIL;