74HC594 8-BIT SHIFT REGISTER WITH 8-BIT OUTPUT REGISTER Description Pin Assignments The 74HC594 is a high speed CMOS device. ( Top View ) An eight bit shift register accepts data from the serial input (DS) on 16 1 Q1 Vcc each positive transition of the shift register clock (SHCP). When 2 15 Q0 asserted low, the shift regisister reset function (SHR) sets all shift Q2 register values to zero and is independent of all clocks. Also when 3 14 DS Q3 asserted low, the storage register reset function (STR) sets all shift 4 13 Q4 STR register values to zero and is independent of all clocks. 5 12 Q5 STCP Data from the input serial shift register is placed in the output register 6 11 Q6 SHCP with a rising pulse on the storages resister clock (STCP). The storage resister includes output Q7S which is used for cascading 7 10 Q7 SHR information between devices. As the information moves into the 9 8 GND Q7S storage register, it is asserted on the push-pull outputs Q0-Q7. SO-16 / TSSOP-16 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. Applications Features General Purpose Logic Wide Supply Voltage Range from 2.0V to 6.0V Serial to Parallel Data conversion Sinks or sources 8mA at V = 4.5V CC Capture and hold data for extended periods of time. CMOS low power consumption Allow simple serial bit streams from a microcontroller to control as Schmitt Trigger Action at All Inputs many peripheral lines as needed. Inputs accept up to 6.0V Wide array of products such as: ESD Protection Tested per JESD 22 Computer Peripherals Exceeds 200-V Machine Model (A115-A) Appliances Exceeds 2000-V Human Body Model (A114-A) Industrial Control 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) Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See 74HC594 Pin Descriptions Functional Diagram Pin Number Pin Name Description 1 Q1 Parallel Data Output 1 2 Q2 Parallel Data Output 2 3 Q3 Parallel Data Output 3 4 Q4 Parallel Data Output 4 5 Q5 Parallel Data Output 5 6 Q6 Parallel Data Output 6 7 Q7 Parallel Data Output 7 8 GND Ground 9 Q7S Serial Data Output 10 Shift Register Reset active low SHR 11 SHCP Shift Register Clock Input 12 STCP Storage Register Clock Input 13 Storage Register Reset active low STR 14 DS Serial Data input 15 Q0 Parallel Data Output 0 16 V Supply Voltage CC Logic Diagram STAGE 0 STAGES 1 TO 6 STAGE 7 DS DQ DQ DQ FF0 FF7 CP CP R R SHCP SHR DQ DQ LATCH LATCH CP CP R R STCP STR Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 2 of 10 June 2013 74AHC594 Diodes Incorporated www.diodes.com Document number: DS35484 Rev. 3 - 2