ST 74VHCT541A User Manual

74VHCT541A

OCTAL BUS BUFFER

WITH 3 STATE OUTPUTS (NON INVERTED)

■ HIGH SPEED: t

■ LOW POWER DISSIPATION:

I

= 4 µA (MAX.) at TA=25°C

CC

■ COMPATIBLE WITH TTL OUTP U TS:

V

= 2V (M IN.), V

IH

■ POWER DOWN PROTECTION ON INPUTS

= 4.1 ns (TYP.) at VCC = 5V

PD

= 0.8V (MAX)

IL

& OUTPUTS

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 8 mA (MIN)

OH

■ BALANCED PROPAGATION DELAYS:

t

≅ t

PLH

PHL

■ OPERATING VOLTAGE RANGE:

V

(OPR) = 4.5V to 5.5V

CC

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 541

■ IMPROVED LATCH-UP IMMUNITY

■ LOW NOISE: V

= 0.9V (MAX.)

OLP

DESCRIPTION

The 74VHCT541A is an advanced high-speed
CMOS OCTAL BUS BUFFER (3-STATE)
fabricated with sub-micron silicon gate and
double-layer metal wiring C

2

MOS technology.
The 3 STATE control gate opera tes as two input
AND such that if either G1

and G2 are high, all

eight outputs are in the high impedance state.

TSSOPSOP

Table 1: Order Codes

PACKAGE T & R

SOP 74VHCT541AMTR

TSSOP 74VHCT541ATTR

In order to enhance PC board layout, the
74VHCT541 offers a pinout having inputs and
outputs on opposite sides of the package.
Power down protection is provided on all inputs
and outputs and 0 to 7V can be accepted on
inputs with no regard to the supply voltage. This
device can be used t o interf ace 5V to 3V s ince al l
inputs are equipped with TTL threshold.
All inputs and outputs are equipped with
protection circuits against static disc harge, giving
them 2KV ESD immunity and transient excess
voltage.

Figure 1: Pin Connection And IEC Logic Symbols

Rev. 4

1/12December 2004

74VHCT541A

Figure 2: Input Equivalent Circuit Table 2: Pin Description

PIN N° SYMBOL NAME AND FUNCTION

1, 19 G1

2, 3, 4, 5, 6,

7, 8, 9

18, 17, 16,
15, 14, 13,

12, 11

10 GND Ground (0V)
20 V

Table 3: Truth Table

INPUT OUTPUT

, G2 Output Enable Inputs

A1 to A8 Data Inputs

Y1 to Y8 Data Outputs

CC

Positive Supply Voltage

G1

G2 An Yn

HXXZ
XHXZ

LLHH
LLLL

X : Don’t Care
Z : High impedance

Table 4: Absolute Maximum Ratings

Symbol Parameter Value Unit

V

V
V
V

I

I

OK

I

I

or I

CC

T

T

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied

1) Output in OFF State

2) High or Low State

Supply Voltage

CC

DC Input Voltage

I

DC Output Voltage (see note 1)

O

DC Output Voltage (see note 2) -0.5 to VCC + 0.5

O

DC Input Diode Current

IK

DC Output Diode Current
DC Output Current

O

DC VCC or Ground Current

GND

Storage Temperature

stg

Lead Temperature (10 sec)

L

-0.5 to +7.0 V

-0.5 to +7.0 V

-0.5 to +7.0 V
V

- 20 mA

± 20 mA
± 25 mA
± 50 mA

-65 to +150 °C

300 °C

2/12

74VHCT541A

Table 5: Recommended Operating Conditions

Symbol Parameter Value Unit

V

V
V
V
T

dt/dv

1) Output in OFF State

2) High or Low State

3) VIN from 0. 8V to 2V

Table 6: DC Specifications

Symbol Parameter

V

IH

V

IL

V

OH

V

OL

I

OZ

I

I

I

CC

+I

CC

I

OPD

Supply Voltage

CC

Input Voltage

I

Output Voltage (see note 1)

O

Output Voltage (see note 2) 0 to V

O

Operating Temperature

op

Input Rise and Fall Time (see note 3) (V

= 5.0 ± 0.5V)

CC

Test Condition Value

= 25°C

T

A

Min. Typ. Max. Min. Max. Min. Max.

222V

0.8 0.8 0.8 V

4.4 4.5 4.4 4.4

3.94 3.8 3.7

0.0 0.1 0.1 0.1

0.36 0.44 0.55

±0.25 ± 2.5 ± 2.5 µA

± 0.1 ± 1.0 ± 1.0 µA

44040µA

1.35 1.5 1.5 mA

0.5 5.0 5.0 µA

High Level Input
Voltage

Low Level Input
Voltage

High Level Output
Voltage

Low Level Output
Voltage

High Impedance
Output Leakage
Current

Input Leakage
Current

Quiescent Supply
Current

Additional Worst
Case Supply
Current

Output Leakage
Current

V

CC

(V)

4.5 to

5.5

4.5 to

5.5

4.5

4.5

4.5

4.5

4.5 to

5.5

0 to

5.5

5.5

5.5

0

=-50 µA

I

O

=-8 mA

I

O

IO=50 µA

I

=8 mA

O

= VIH or V

V

I

IL

VO = 0V to 5.5V

V

= 5.5V or GND

I

= VCC or GND

V

I

One Input at 3.4V,
other input at V

CC

or GND

= 5.5V

V

OUT

4.5 to 5.5 V
0 to 5.5 V
0 to 5.5 V

CC

-55 to 125 °C
0 to 20 ns/V

-40 to 85°C -55 to 125°C

V

Unit

V

V

Table 7: AC Electrical Characteristics (Input t

Test Condition Value

Symbol Parameter

t

Propagation Delay

PLH
PHL

PZL

PZH

PLZ

PHZ

Time
Output Disable

Time
Output Enable

Time

t
t

t
t

t

(*) Voltage range is 5.0V ± 0.5V

V

(*)

(V)

C

(pF)

L

CC

5.0 15 4.1 6.0 1.0 6.5 1.0 6.5

5.0 50 6.2 8.5 1.0 9.5 1.0 9.5

5.0 15

5.0 50 7.5 10.0 1.0 12.0 1.0 12.0

RL = 1K

5.0 50 RL = 1K

= tf = 3ns)

r

= 25°C

T

A

-40 to 85°C -55 to 125°C

Min. Typ. Max. Min. Max. Min. Max.

Ω

Ω 7.0 10.0 1.0 12.0 1.0 12.0 ns

5.0 7.0 1.0 8.0 1.0 8.0

Unit

ns

ns

3/12

74VHCT541A

Table 8: Capacitive Characteristics

Test Condition Value

= 25°C

Symbol Parameter

T

A

Min. Typ. Max. Min. Max. Min. Max.

C

C

C

Input Capacitance

IN

Output

OUT

Capacitance
Power Dissipation

PD

Capacitance

610 10 10pF
8pF

16 pF

(note 1)

1) CPD is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I

Table 9: Dynamic Switching Characteristics

Test Condition Value

= 25°C

Symbol Parameter

V
V

Dynamic Low

OLP

Voltage Quiet

OLV

Output (note 1, 2)
Dynamic High

V

IHD

Voltage Input
(note 1, 3)

Dynamic Low

V

ILD

Voltage Input
(note 1, 3)

V

CC

(V)

5.0

= 50 pF

5.0 2.0

C

L

5.0 0.8

T

A

Min. Typ. Max. Min. Max. Min. Max.

0.9 1.1

-1.1 -0.9

-40 to 85°C -55 to 125°C

= CPD x VCC x fIN + ICC/8 (per c ircuit )

CC(opr)

-40 to 85°C -55 to 125°C

Unit

Unit

V

1) Worst case package.

2) Max number of outp ut s defined as (n). Data inpu t s are driven 0V to 3.0V, (n-1) outputs switc hi ng and one output at GND.

3) Max number of data inputs (n) switching. (n-1) switching 0V to 3.0V. Inputs under test switching: 3.0V to threshold (V
(V

), f=1MHz.

IHD

ILD

), 0V to thresho l d

4/12