74VHCT20A
DUAL 4-INPUT NAND GATE
■ HIGH SPEED: t
■ LOW POWER DISSIPATION:
I
= 2 µA (MAX.) at TA=25°C
CC
■ COMPA TIBLE WITH TTL OUTPUTS:
V
= 2V (MIN.), V
IH
■ POWER DOWN PROTECTION ON INPUTS
= 5 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
■ OPERATING VOLTAGE RANGE:
V
CC
■ PIN AND FUNCTION COMPATIBLE WITH
PHL
(OPR) = 4.5V to 5.5V
74 SERIES 20
■ IMPROVED LATCH-UP IMMUNITY
DESCRIPTION
The 74VHCT20A is an advanced high-speed
CMOS DUAL 4-INPUT NAND GATE fabricated
with sub-micron silicon gate and double-layer
metal wiring C
2
MOS technology.
The internal circuit is composed of 3 stages
including buffer ou tput, which provides high noise
immunity and stable output.
TSSOPSOP
ORDER CODES
PACKAGE TUBE T & R
SOP 74VHCT20AM 74VHCT20AMTR
TSSOP 74VHCT20ATTR
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 us ed to interf ac e 5V to 3V since al l
inputs are equipped with TTL threshold.
All inputs and outputs are equipped with
protection circuits against stat ic discharge, giving
them 2KV ESD immunity and transient excess
voltage.
PIN CONNECTION AND IEC LOGIC SYMBOLS
1/7June 2001
74VHCT20A
INPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
PIN No SYMBOL NAME AND FUNCTION
1, 9 1A to 2A Data Inputs
2, 10 1B to 2B Data Inputs
3, 11 N.C. Not Connected
4, 12 1C to 2C Data Inputs
5, 13 1D to 2D Data Inputs
6, 8 1Y to 2Y Data Outputs
7 GND Ground (0V)
14
TRUTH TABLE
ABCDY
LXXXH
XLXXH
XXLXH
XXXLH
HHHHL
X : Don‘t Care
V
CC
Positive Supply Voltage
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) V
CC
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
= 0V
-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
RECOMMENDED OPERATING CONDITIONS
Symbol Parameter Value Unit
V
V
V
V
T
dt/dv
1) V
CC
2) High or Low State
3) V
from 0.8V to 2V
IN
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
= 0V
= 5.0 ± 0.5V)
CC
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
V
2/7
DC SPECIFICATIONS
Symbol Parameter
V
V
V
V
I
I
OPD
High Level Input
IH
Voltage
Low Level Input
IL
Voltage
High Level Output
OH
Voltage
Low Level Output
OL
Voltage
I
Input Leakage
I
Current
Quiescent Supply
CC
Current
I
Additional Worst
CC
Case Supply
Current
Output Leakage
Current
Test Condition Value
T
= 25°C
V
CC
(V)
4.5 to
5.5
A
Min. Typ. Max. Min. Max. Min. Max.
222V
4.5 to
5.5
4.5
4.5
4.5
4.5
0 to
5.5
5.5
IO=-50 µA
I
=-8 mA
O
IO=50 µA
=8 mA
I
O
V
= 5.5V or GND
I
= VCC or GND
V
I
4.4 4.5 4.4 4.4
3.94 3.8 3.7
0.0 0.1 0.1 0.1
One Input at 3.4V,
other input at V
5.5
CC
or GND
= 5.5V
0
V
OUT
74VHCT20A
-40 to 85°C -55 to 125°C
0.8 0.8 0.8 V
0.36 0.44 0.55
± 0.1 ± 1.0 ± 1.0 µA
22020µA
1.35 1.5 1.5 mA
0.5 5.0 5.0 µA
Unit
V
V
AC ELECTRICAL CHARACTERISTICS (Input t
= tf = 3ns)
r
Test Condition Value
= 25°C
Symbol Parameter
t
Propagation Delay
PLH
PHL
Time
t
(*) Vol tage range is 5.0V ± 0.5V
V
(*)
(V)
C
(pF)
L
CC
5.0 15 5.0 7.0 1.0 8.0 1.0 8.0
5.0 50 5.5 8.0 1.0 9.0 1.0 9.0
T
A
-40 to 85°C -55 to 125°C
Min. Typ. Max. Min. Max. Min. Max.
Unit
ns
CAPACITIVE CHARACTERISTICS
Test Condition Value
= 25°C
Symbol Parameter
T
A
Min. Typ. Max. Min. Max. Min. Max.
C
C
Input Capacitance
IN
Power Dissipation
PD
Capacitance
6101010pF
15 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. (R efer to Test Circuit). Average curre nt can be obtai ned by the following equa t i on. I
CC(opr)
-40 to 85°C -55 to 125°C
= CPD x VCC x fIN + ICC/2 (per gate)
Unit
3/7