Philips Semiconductors
Product specification
32-bit buffer/line driver; 5 V input/output
tolerant; 3-state
FEATURES
•
5 V tolerant inputs/outputs for interfacing with 5 V logic
•
Wide supply voltage range of 1.2 to 3.6 V
•
CMOS low power consumption
•
MULTIBYTE™ flow-trough standard pin-out architecture
•
Low inductance multiple power and ground pins for
minimum noise and ground bounce
•
Direct interface with TTL levels
•
Bus hold on data inputs (74LVCH32244A only)
•
Typical output ground bounce voltage:
V
OLP
<0.8 V at V
CC
= 3.3 V; T
amb
= 25
°C
•
Typical output V
OH
undershoot voltage:
V
OHV
>2 V at V
CC
= 3.3 V; T
amb
= 25
°C
•
Power-off disabled outputs, permitting live insertion
•
Plastic fine-pitch ball grid array package.
DESCRIPTION
74LVC32244A;
74LVCH32244A
The 74LVC(H)32244A is a high-performance, low-power,
low-voltage, Si-gate CMOS device, superior to most
advanced CMOS compatible TTL families. Inputs can be
driven from either 3.3 or 5 V devices. In 3-state operation,
outputs can handle 5 V. These features allow the use of
these devices in a mixed 3.3 and 5 V environment.
The 74LVC(H)32244A is a 32-bit non-inverting buffer/line
driver with 3-state outputs. The 3-state outputs are
controlled by the output enable inputs 1OE and 2OE.
A HIGH on input nOE causes the outputs to assume a
high-impedance OFF-state.
To ensure the high-impedance state during power-up or
power-down, input nOE should be tied to V
CC
through a
pull-up resistor; the minimum value of the resistor is
determined by the current-sinking capability of the driver.
The 74LVCH32244A bus hold data input circuit eliminates
the need for external pull-up resistors to hold unused or
floating data inputs at a valid logic level (see Fig.3).
QUICK REFERENCE DATA
Ground = 0 V; T
amb
= 25
°C;
t
r
= t
f
≤
2.5 ns.
SYMBOL
t
PHL
/t
PLH
C
I
C
PD
Note
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
µW).
P
D
= C
PD
×
V
CC2
×
f
i
+
Σ(C
L
×
V
CC2
×
f
o
) where:
f
i
= input frequency in MHz;
f
o
= output frequency in MHz;
C
L
= output load capacitance in pF;
V
CC
= supply voltage in Volts;
Σ(C
L
×
V
CC2
×
f
o
) = sum of the outputs.
PARAMETER
propagation delay nA
n
to nY
n
input capacitance
power dissipation capacitance per buffer
V
I
= GND to V
CC
; note 1
CONDITIONS
C
L
= 50 pF; V
CC
= 3.3 V
TYPICAL
3.0
5.0
25
ns
pF
pF
UNIT
1999 Aug 31
2
京公网安备 11010802033920号
EEWORLD
