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LM555/LM555C Timer

May 1997

LM555/LM555C Timer
General Description
The LM555 is a highly stable device for generating accurate time delays or oscillation. Additional terminals are provided for triggering or resetting if desired. In the time delay mode of operation, the time is precisely controlled by one external resistor and capacitor. For astable operation as an oscillator, the freerunning frequency and duty cycle are accurately controlled with two external resistors and one capacitor. The circuit may be triggered and reset on falling waveforms, and the output circuit can source or sink up to 200 mA or drive TTL circuits.

Features
n n n n n n n n n Direct replacement for SE555/NE555 Timing from microseconds through hours Operates in both astable and monostable modesAdjustable duty cycle Output can source or sink 200 mA Output and supply TTL compatible Temperature stability better than 0.005% per ˚C Normally on and normally off output Available in 8 pin MSOP package

Applications
n n n n n n n Precision timing Pulse generation Sequential timing Time delay generation Pulse width modulation Pulse position modulation Linear ramp generator

Schematic DiagramDS007851-1

© 1997 National Semiconductor Corporation

DS007851

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Absolute Maximum Ratings

(Note 2)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Power Dissipation (Note 3) LM555H, LM555CH LM555, LM555CN LM555CMM Operating Temperature RangesLM555C LM555 +18V 760 mW 1180 mW 613 mW 0˚C to +70˚C −55˚C to + 125˚C

Storage Temperature Range −65˚C to +150˚C Soldering Information Dual-In-Line Package Soldering (10 Seconds) 260˚C Small Outline Packages (SOIC and MSOP) Vapor Phase (60 Seconds) 215˚C Infrared (15 Seconds) 220˚C See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of solderingsurface mount devices.

Electrical Characteristics (Notes 1, 2) (TA = 25˚C, VCC = +5V to +15V, unless othewise specified)
Limits Parameter Supply Voltage Supply Current VCC = 5V, RL = ∞ VCC = 15V, RL = ∞ (Low State) (Note 4) Timing Error, Monostable Initial Accuracy Drift with Temperature Accuracy over Temperature Drift with Supply Timing Error, Astable Initial Accuracy Drift with TemperatureAccuracy over Temperature Drift with Supply Threshold Voltage Trigger Voltage Trigger Current Reset Voltage Reset Current Threshold Current Control Voltage Level Pin 7 Leakage Output High Pin 7 Sat (Note 7) Output Low Output Low VCC = 15V, I7 = 15 mA VCC = 4.5V, I7 = 4.5 mA 150 70 100 180 80 200 mV mV (Note 6) VCC = 15V VCC = 5V 9.6 2.9 0.4 VCC = 15V VCC = 5V 4.8 1.45 RA, RB = 1k to 100 kΩ, C = 0.1 µF,(Note 5) 1.5 90 2.5 0.15 0.667 5 1.67 0.01 0.5 0.1 0.1 10 3.33 1 5.2 1.9 0.5 1 0.4 0.25 10.4 3.8 100 9 2.6 0.4 2.25 150 3.0 0.30 0.667 5 1.67 0.5 0.5 0.1 0.1 10 3.33 1 0.9 1 0.4 0.25 11 4 100 % ppm/˚C % %/V x VCC V V µA V mA µA V V nA RA = 1k to 100 kΩ, C = 0.1 µF, (Note 5) 0.5 30 1.5 0.05 1 50 1.5 0.1 % ppm/˚C % %/V Conditions Min 4.5 3 10 LM555 Typ Max 18 5 12 Min 4.5 3 10 LM555C Typ Max 16 6 15V mA mA Units

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Electrical Characteristics

(Notes 1, 2) (Continued)

(TA = 25˚C, VCC = +5V to +15V, unless othewise specified) Limits Parameter Output Voltage Drop (Low) Conditions Min VCC = 15V ISINK = 10 mA ISINK = 50 mA ISINK = 100 mA ISINK = 200 mA VCC = 5V ISINK = 8 mA ISINK = 5 mA ISOURCE = 200 mA, VCC = 15V ISOURCE = 100 mA, VCC = 15V VCC = 5V LM555 Typ 0.10.4 2 2.5 0.1 12.5 13 3 13.3 3.3 100 100 12.75 2.75 0.25 0.25 12.5 13.3 3.3 100 100 0.35 Max 0.15 0.5 2.2 Min LM555C Typ 0.1 0.4 2 2.5 Max 0.25 0.75 2.5 V V V V V V V V V ns ns Units

Output Voltage Drop (High)

Rise Time of Output Fall Time of Output
Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.

Note 2: Absolute Maximum Ratings indicate...