CD54HC646, CD74HCT646

OCTAL BUS TRANSCEIVERS AND REGISTERS

WITH 3-STATE OUTPUTS

SCHS278B – APRIL 2003 – REVISED APRIL 2003

5

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†

Supply voltage range, VCC

–0.5 V to 7 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input clamp current, IIK (VI < 0 or VI > VCC) (see Note 1)

±20 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Output clamp current, IOK (VO < 0 or VO > VCC) (see Note 1)

±20 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Continuous output drain current per output, IO (VO = 0 to VCC)

±35 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Continuous current through VCC or GND

±50 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Package thermal impedance,

θJA (see Note 2) M package

46

°C/W

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storage temperature range, Tstg

–65

°C to 150°C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTES:

1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.

2. The package thermal impedance is calculated in accordance with JESD 51-7.

recommended operating conditions for CD54HC646 (see Note 3)

MIN

MAX

UNIT

VCC

Supply voltage

2

6

V

VCC = 2 V

1.5

VIH

High-level input voltage

VCC = 4.5 V

3.15

V

VCC = 6 V

4.2

VCC = 2 V

0.5

VIL

Low-level input voltage

VCC = 4.5 V

1.35

V

VCC = 6 V

1.8

VI

Input voltage

0

VCC

V

VO

Output voltage

0

VCC

V

VCC = 2 V

1000

tt

Input transition (rise and fall) time

VCC = 4.5 V

500

ns

VCC = 6 V

400

TA

Operating free-air temperature

–55

125

°C

NOTE 3: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,

Implications of Slow or Floating CMOS Inputs, literature number SCBA004.

recommended operating conditions for CD74HCT646 (see Note 3)

MIN

MAX

UNIT

VCC

Supply voltage

4.5

5.5

V

VIH

High-level input voltage

2

V

VIL

Low-level input voltage

0.8

V

VI

Input voltage

VCC

V

VO

Output voltage

VCC

V

tt

Input transition (rise and fall) time

500

ns

TA

Operating free-air temperature

–55

125

°C

NOTE 4: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,

Implications of Slow or Floating CMOS Inputs, literature number SCBA004.