MC74VHC595
www.onsemi.com
4
FUNCTION TABLE
Operation
Inputs Resulting Function
Reset
(SCLR
)
Serial
Input
(SI)
Shift
Clock
(SCK)
Reg
Clock
(RCK)
Output
Enable
(OE)
Shift
Register
Contents
Storage
Register
Contents
Serial
Output
(SQH)
Parallel
Outputs
(QA − QH)
Clear shift register L X X L, H, ↓ L L U L U
Shift data into shift
register
H D ↑ L, H, ↓ L D→SR
A
;
SR
N
→SR
N+1
U SR
G
→SR
H
U
Registers remains
unchanged
H X L, H, ↓ X L U ** U **
Transfer shift register
contents to storage
register
H X L, H, ↓ ↑ L U SR
N
³STR
N
* SR
N
Storage register remains
unchanged
X X X L, H, ↓ L * U * U
Enable parallel outputs X X X X L * ** * Enabled
Force outputs into high
impedance state
X X X X H * ** * Z
SR = shift register contents D = data (L, H) logic level ↓ = High−to−Low * = depends on Reset and Shift Clock inputs
STR = storage register contents U = remains unchanged ↑ = Low−to−High ** = depends on Register Clock input
MAXIMUM RATINGS*
Symbol Parameter Value Unit
V
CC
DC Supply Voltage – 0.5 to + 7.0 V
V
in
DC Input Voltage – 0.5 to + 7.0 V
V
out
DC Output Voltage – 0.5 to V
CC
+ 0.5 V
I
IK
Input Diode Current − 20 mA
I
OK
Output Diode Current ± 20 mA
I
out
DC Output Current, per Pin ± 25 mA
I
CC
DC Supply Current, V
CC
and GND Pins ± 50 mA
P
D
Power Dissipation in Still Air, SOIC Packages†
TSSOP Package†
500
450
mW
T
stg
Storage Temperature – 65 to + 150
_C
Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of
these limits are exceeded, device functionality should not be assumed, damage may occur and
reliability may be affected.
†Derating — SOIC Packages: – 7 mW/_C from 65_ to 125_C
TSSOP Package: − 6.1 mW/_C from 65_ to 125_C
RECOMMENDED OPERATING CONDITIONS
Symbol Parameter Min Max Unit
V
CC
DC Supply Voltage 2.0 5.5 V
V
in
DC Input Voltage 0 5.5 V
V
out
DC Output Voltage 0 V
CC
V
T
A
Operating Temperature, All Package Types − 55 + 125
_C
t
r
, t
f
Input Rise and Fall Time V
CC
= 3.3V ±0.3V
V
CC
=5.0V ±0.5V
0
0
100
20
ns/V
Functional operation above the stresses listed in the Recommended Operating Ranges is not
implied. Extended exposure to stresses beyond the Recommended Operating Ranges limits may
affect device reliability.
This device contains protection
circuitry to guard against damage
due to high static voltages or electric
fields. However, precautions must
be taken to avoid applications of any
voltage higher than maximum rated
voltages to this high−impedance cir-
cuit. For proper operation, V
in
and
V
out
should be constrained to the
range GND v (V
in
or V
out
) v V
CC
.
Unused inputs must always be
tied to an appropriate logic voltage
level (e.g., either GND or V
CC
).
Unused outputs must be left open.
