Document
74HC595
8-BIT SHIFT REGISTER WITH 8-BIT OUTPUT REGISTER
Description
The 74HC595 is an high speed CMOS device.
An eight bit shift register accpets data from the serial input (DS) on each positive transition of the shift register clock (SHCP). When asserted low the reset function ( ) sets all shift register values to zero and is indepent of all clocks.
Data from the input serial shift register is placed in the output register with a rising pulse on the storages resister clock (STCP). With the output enable ( E asserted low the 3-state outputs Q0-Q7 become active and present th
All registers capture data on rising edge and change output on the falling edge. If both clocks are connected together the input shift register is always one clock cycle ahead of the output register.
Pin Assignments
Q1 Q2 Q3 Q4 Q5 Q6 Q7 GND
( Top View )
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
Vcc Q0 DS OE STCP SHCP MR Q7S
SO-16 / TSSOP-16
Features
Wide Supply Voltage Range from 2.0V to 6.0V Sinks or Sources 8mA at VCC = 4.5V CMOS Low Power Consumption Schmitt Trigger Action at All Inputs Inputs Accept up to 6.0V ESD Protection Tested per JESD 22
Exceeds 200-V Machine Model (A115-A) Exceeds 2000-V Human Body Model (A114-A) Exceeds 1000-V Charged Device Model (C101C) Latch-Up Exceeds 250mA per JESD 78, Class II Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. “Green” Device (Note 3)
Applications
General Purpose Logic Serial to Parallel Data Conversion Capture and Hold Data for Extended Periods of Time Allow Simple Serial Bit Streams from a Microcontroller to Control
as Many Peripheral Lines as Needed Wide Array of Products such as:
Computer Peripherals Appliances Industrial Control
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. 2. See https://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free. 3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
74HC595
Document number: DS35492 Rev. 4 - 2
1 of 11 www.diodes.com
November 2018
© Diodes Incorporated
Pin Descriptions
Pin Number 1 2 3 4 5 6 7 8 9 10
11 12 13
14 15 16
Pin Name Q1 Q2 Q3 Q4 Q5 Q6 Q7 GND Q7S
SHCP STCP
E DS Q0 VCC
Function Parallel Data Output 1 Parallel Data Output 2 Parallel Data Output 3 Parallel Data Output 4 Parallel Data Output 5 Parallel Data Output 6 Parallel Data Output 7 Ground Serial Data Output Master Reset Input Shift Register Clock Input Storage Register Clock Input Output Enable Input Serial Data Input Parallel Data Output 0 Supply Voltage
Logic Diagram
74HC595
Functional Diagram
14 DS 11 SHCP 10 MR
12 STCP
8-Stage Shift Register
Q7S 9
8-Bit Storage Register
13 OE
3-State Outputs
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 15 1 2 3 4 5 6 7
DS SHCP
MR
STCP OE
STAGE 0
D
Q
FF0
CP R
STAGES 1 TO 6
D
Q
STAGE 7
D
Q
FF7
CP R
Q7S
D
Q
LATCH
CP
D
Q
LATCH
CP
Q0
Q1 Q2 Q3 Q4 Q5 Q6
Q7
74HC595
Document number: DS35492 Rev. 4 - 2
2 of 11 www.diodes.com
November 2018
© Diodes Incorporated
74HC595
Functional Description and Timing Diagram
Control SHCP STCP
X
X
L
X
L
X
X
H
X
L
X
L
L
Input DS
L
L
L
H
H
H
Output
Q7S
Qn
L
NC
L
L
L
Z
Q6S
NC
NC
QnS
Q6S
QnS
Function
Low-level asserted on MR clears shift register. Storage register is unchanged. Empty shift register transferred to storage register.
Shift register remains clear; All Q ouputs in Z state. HIGH is shifted into first stage of Shift Register Contents of each register shifted to next register. The content of Q6S has been shifted to Q7S and now appears on device pin Q7S. Contents of shift register copied to storage register. With output now in active state the storage resister contents appear on Q outputs. Contents of shift register copied to output register then shift register shifted.
H=HIGH Voltage State L=LOW Voltage State =LOW to HIGH Transition X= Don’T Care – High or Low (Not Floating) NC= No Change Z= High-Impedance State
SHCP
DS STCP
MR
OE Q0 Q1 Q6 Q7 Q7S
Z-state Z-state Z-state Z-state
74HC595
Document number: DS35492 Rev. 4 - 2
3 of 11 www.diodes.com
November 2018
© Diodes Incorporated
74HC595
Absolute Maximum Ratings (Note 4) (@TA = +25°C, unless otherwise specified.)
Symbol
Description
Rating
Unit
ESD HBM
Human Body Model ESD Protection
2
kV
ESD CDM
Charged Device Model ESD Protection
1
kV
ESD MM
Machine Model ESD Protection
200
V
VCC
Supply Voltage Range
-0.5 to +7.0
V
VI
Input Voltage Range
-0.5 to +7.0
V
Vo
Voltage Applied to Output in High or Low State
-0.3 to VCC +0.5
V
IIK
Input Clamp Current VI < -0.5V
-20
mA
.