LMC555 CMOS Timer - General Description - Features - Ordering Information - Electrical Characteristics

Nov 1, 2026

Uploaded by Theodore

LMC555 CMOS Timer overview describes a CMOS implementation of the industry-standard 555 general-purpose timer, offering accurate delay and oscillation timing with lower power dissipation and reduced supply-current spikes compared with LM555. One-shot timing is controlled by a single external resistor and capacitor, while astable operation uses two resistors and one capacitor to set frequency and duty cycle. Features highlight low-power operation, guaranteed low-voltage supply, TTL/CMOS compatible output, pin compatibility, and multiple 8-pin package options. The document also includes connection, ratings, soldering, and electrical characteristic tables.

LanguageEnglish

CategoryTechnology

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Pages13

Reading Time33 min

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LMC555 CMOS Timer

General Description

Features

Ordering Information

Absolute Maximum Ratings

Operating Ratings and Thermal Resistance

Electrical Characteristics

| | | May 2006 | | | | | --- | --- | --- | --- | --- | --- | | LMC555 CMOS Timer General Description
The LMC555 is a CMOS version of the industry standard 555 series general purpose timers. In addition to the standard package (SOIC, MSOP, and MDIP) the LMC555 is also available in a chip sized package (8 Bump micro SMD) using National’s micro SMD package technology. The LMC555 offers the same capability of generating accurate time delaysand frequencies as the LM555 but with much lower power dissipation and supply current spikes. When operated as a one-shot, the time delay is precisely controlled by a single external resistor and capacitor. In the stable mode the oscillation frequency and duty cycle are accurately set by two external resistors and one capacitor. The use of National Semiconductor’s LMCMOS™ process extends both the frequency range and low supply capability. | | | Features
n Less than 1 mW typical power dissipation at 5V supply n 3 MHz astable frequency capability
n 1.5V supply operating voltage guaranteed
n Output fully compatible with TTL and CMOS logic at 5V supply
n Tested to −10 mA, +50 mA output current levels n Reduced supply current spikes during output transitionsn Extremely low reset, trigger, and threshold currents n Excellent temperature stability
n Pin-for-pin compatible with 555 series of timersn Available in 8-pin MSOP Package and 8-Bump micro
SMD package | | | | Pulse Width Modulator | | | | | | |
00866920 | | |
00866915 | | | | Ordering Information | | | | | | | Package | Temperature Range | Package Marking | | Transport Media | NSC Drawing | | | Industrial
−40˚C to +85˚C | | | | | | 8-Pin Small Outline (SO) | LMC555CM | LMC555CM | | Rails | M08A | | | LMC555CMX | | | 2.5k Units Tape and Reel | | | 8-Pin Mini Small Outline
(MSOP) | LMC555CMM | ZC5 | | 1k Units Tape and Reel | MUA08A | | | LMC555CMMX | | | 3.5k Units Tape and Reel | | | 8-Pin Molded Dip (MDIP) | LMC555CN | LMC555CN | | Rails | N08E | | 8-Bump micro SMD | LMC555CBP | F1 | | 250 Units Tape and Reel | BPA08EFB | | | LMC555CBPX | | | 3k Units Tape and Reel | | | 8-Bump micro SMD
NOPB | LMC555CTP | F02 | | 250 Units Tape and Reel | TPA08EFA | | | LMC555CTPX | | | 3k Units Tape and Reel | | | Note: See Mil-datasheet MNLMC555-X for specifications on the military device LMC555J/883 .
LMCMOS™ is a trademark of National Semiconductor Corp. | | | | | | © 2006 National Semiconductor Corporation DS008669 [www.national.com](www.national.com) LMC555 CMOS Timer LMC555 Connection Diagrams 8-Pin SOIC, MSOP, MDIP 00866901 Top View 8-Bump micro SMD 00866909 Top View (Bump Side Down) [www.national.com](www.national.com) 2 | Absolute Maximum Ratings (Notes 2, 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.
Supply Voltage, V+ 15V
Input Voltages, VTRIG, VRES, VCTRL,
VTHRESH −0.3V to VS + 0.3V
Output Voltages, VO, VDIS 15V
Output Current IO, IDIS 100 mA
Storage Temperature Range −65˚C to +150˚C
Soldering Information
MDIP Soldering (10 seconds) 260˚CSOIC, MSOP Vapor Phase (60 sec) 215˚CSOIC, MSOP Infrared (15 sec) 220˚C
Note: See AN-450 “Surface Mounting Methods and Their Effect on Product
Reliability” for other methods of soldering surface mount devices. Operating Ratings(Notes 2, 3)
Termperature
Range −40˚C to +85˚C | | | Thermal Resistance (θJA) (Note 2)
SO, 8-Pin Small
Outline 169˚C/W
MSOP, 8-Pin Mini Small
Outline 225˚C/W
MDIP, 8-Pin
Molded Dip 111˚C/W
8-Bump micro
SMD 220˚C/W
Maximum Allowable Power Dissipation @25˚C
MDIP-8 1126 mW
SO-8 740 mW
MSOP-8 555 mW
8 Bump micro
SMD 568 mW | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | Electrical Characteristics (Notes 1, 2)
Test Circuit, T = 25˚C, all switches open, RESET to VS un

FAQs

How does the LMC555 control timing in one-shot mode?

In one-shot operation, the time delay is precisely controlled by a single external resistor and capacitor.

How are oscillation frequency and duty cycle set in stable (astable) mode?

In stable mode, oscillation frequency and duty cycle are accurately set using two external resistors and one capacitor.

What are key benefits of the LMC555 compared with the LM555?

The LMC555 provides the same timing capability while using much lower power dissipation and with reduced supply current spikes during output transitions.

Nov 1, 2026

Uploaded by Theodore