Datasheet NA555, NE555, SA555, SE555 (Texas Instruments)

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NA555, NE555, SA555, SE555
SLFS022I – SEPTEMBER 1973 – REVISED SEPTEMBER 2014
xx555 Precision Timers 1 Features 3 Description
These devices are precision timing circuits capable of • Timing From Microseconds to Hours 1 producing accurate time delays or oscillation. In the • Astable or Monostable Operation time-delay or mono-stable mode of operation, the • Adjustable Duty Cycle timed interval is controlled by a single external • TTL-Compatible Output Can Sink or Source resistor and capacitor network. In the a-stable mode of operation, the frequency and duty cycle can be Up to 200 mA controlled independently with two external resistors • On Products Compliant to MIL-PRF-38535, and a single external capacitor. All Parameters Are Tested Unless Otherwise The threshold and trigger levels normally are two- Noted. On All Other Products, Production thirds and one-third, respectively, of VCC. These Processing Does Not Necessarily Include levels can be altered by use of the control-voltage Testing of All Parameters. terminal. When the trigger input falls below the trigger level, the flip-flop is set, and the output goes high. If
2 Applications
the trigger input is above the trigger level and the • Fingerprint Biometrics threshold input is above the threshold level, the flip- flop is reset and the output is low. The reset (RESET) • Iris Biometrics input can override all other inputs and can be used to • RFID Reader initiate a new timing cycle. When RESET goes low, the flip-flop is reset, and the output goes low. When the output is low, a low-impedance path is provided between discharge (DISCH) and ground. The output circuit is capable of sinking or sourcing current up to 200 mA. Operation is specified for supplies of 5 V to 15 V. With a 5-V supply, output levels are compatible with TTL inputs.
Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM)
PDIP (8) 9.81 mm × 6.35 mm SOP (8) 6.20 mm × 5.30 mm xx555 TSSOP (8) 3.00 mm × 4.40 mm SOIC (8) 4.90 mm × 3.91 mm (1) For all available packages, see the orderable addendum at the end of the datasheet.
4 Simplified Schematic VCC RESET 8 CONT 4
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1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. Document Outline 1 Features 2 Applications 3 Description 4 Simplified Schematic Table of Contents 5 Revision History 6 Pin Configuration and Functions 7 Specifications 7.1 Absolute Maximum Ratings 7.2 Handling Ratings 7.3 Recommended Operating Conditions 7.4 Electrical Characteristics 7.5 Operating Characteristics 7.6 Typical Characteristics 8 Detailed Description 8.1 Overview 8.2 Functional Block Diagram 8.3 Feature Description 8.3.1 Mono-stable Operation 8.3.2 A-stable Operation 8.3.3 Frequency Divider 8.4 Device Functional Modes 9 Applications and Implementation 9.1 Application Information 9.2 Typical Applications 9.2.1 Missing-Pulse Detector 9.2.1.1 Design Requirements 9.2.1.2 Detailed Design Procedure 9.2.1.3 Application Curves 9.2.2 Pulse-Width Modulation 9.2.2.1 Design Requirements 9.2.2.2 Detailed Design Procedure 9.2.2.3 Application Curves 9.2.3 Pulse-Position Modulation 9.2.3.1 Design Requirements 9.2.3.2 Detailed Design Procedure 9.2.3.3 Application Curves 9.2.4 Sequential Timer 9.2.4.1 Design Requirements 9.2.4.2 Detailed Design Procedure 9.2.4.3 Application Curves 10 Power Supply Recommendations 11 Device and Documentation Support 11.1 Related Links 11.2 Trademarks 11.3 Electrostatic Discharge Caution 11.4 Glossary 12 Mechanical, Packaging, and Orderable Information