Datasheet LM556 (Texas Instruments) - 3

LM556 www.ti.com
SNAS549A – MARCH 2000 – REVISED OCTOBER 2015
5 Pin Configuration and Functions D or NFF Package 14-Pin SOIC or PDIP Top View
1 14 DISCHARGE VCC 2 13 THRESHOLD DISCHARGE 3 12 CTRL VOLTAGE THRESHOLD 4 11 RESET CTRL VOLTAGE 5 10 OUTPUT RESET 6 9 TRIGGER OUTPUT 7 8 GND TRIGGER
Pin Functions PIN I/O DESCRIPTION NAME NO.
CONTROL Controls the threshold and trigger levels. It determines the pulse width of the output VOLTAGE 3 I waveform. An external voltage applied to this pin can also be used to modulate the output (Timer 0) waveform. CONTROL Controls the threshold and trigger levels. It determines the pulse width of the output VOLTAGE 11 I waveform. An external voltage applied to this pin can also be used to modulate the output (Timer 1) waveform. DISCHARGE Open collector output which discharges a capacitor between intervals (in phase with output). 1 I (Timer 0) It toggles the output from high to low when voltage reaches 2/3 of supply voltage. DISCHARGE Open collector output which discharges a capacitor between intervals (in phase with output). 13 I (Timer 1) It toggles the output from high to low when voltage reaches 2/3 of supply voltage. GND 7 O Ground reference voltage OUTPUT 5 O Output driven waveform (Timer 0) OUTPUT 9 O Output driven waveform (Timer 1) RESET Negative pulse applied to this pin to disable or reset the timer. When not used for reset 4 I (Timer 0) purposes, it should be connected to Vcc to avoid false triggering. RESET Negative pulse applied to this pin to disable or reset the timer. When not used for reset 10 I (Timer 1) purposes, it should be connected to Vcc to avoid false triggering. THRESHOLD Compares the voltage applied to the terminal with a reference voltage of 2/3 VCC. The 2 I (Timer 0) amplitude of voltage applied to this terminal is responsible for the set state of the flip-flop. TRIGGER Responsible for transition of the flip-flop from set to reset. The output of the timer depends 6 I (Timer 0) on the amplitude of the external trigger pulse applied to this pin. THRESHOLD Compares the voltage applied to the terminal with a reference voltage of 2/3 VCC. The 12 I (Timer 1) amplitude of voltage applied to this terminal is responsible for the set state of the flip-flop. TRIGGER Responsible for transition of the flip-flop from set to reset. The output of the timer depends 8 I (Timer 1) on the amplitude of the external trigger pulse applied to this pin. VCC 14 I Supply voltage with respect to GND Copyright © 2000–2015, Texas Instruments Incorporated Submit Documentation Feedback 3 Product Folder Links: LM556 Document Outline 1 Features 2 Applications 3 Description Table of Contents 4 Revision History 5 Pin Configuration and Functions 6 Specifications 6.1 Absolute Maximum Ratings 6.2 ESD Ratings 6.3 Recommended Operating Conditions 6.4 Thermal Information 6.5 Electrical Characteristics 6.6 Typical Characteristics 7 Detailed Description 7.1 Overview 7.2 Functional Block Diagram 7.3 Feature Description 7.3.1 Operating Characteristics 7.3.2 Timing from Microseconds Through Hours 7.4 Device Functional Modes 7.4.1 Monostable Mode 7.4.2 Astable (Free-Running) Mode 8 Application and Implementation 8.1 Application Information 8.2 Typical Application 8.2.1 Design Requirements 8.2.2 Detailed Design Procedure 8.2.3 Application Curve 9 Power Supply Recommendations 10 Layout 10.1 Layout Guidelines 10.2 Layout Example 11 Device and Documentation Support 11.1 Documentation Support 11.1.1 Related Documentation 11.2 Community Resources 11.3 Trademarks 11.4 Electrostatic Discharge Caution 11.5 Glossary 12 Mechanical, Packaging, and Orderable Information