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LMC555
SNAS558M – FEBRUARY 2000 – REVISED JULY 2016
LMC555 CMOS Timer
1 Features
3 Description
•
•
The LMC555 device is a CMOS version of the
industry standard 555 series general-purpose timers.
In addition to the standard package (SOIC, VSSSOP,
and PDIP) the LMC555 is also available in a chipsized package (8-bump DSBGA) using TI's DSBGA
package technology. The LMC555 offers the same
capability of generating accurate time delays and
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
astable mode the oscillation frequency and duty cycle
are accurately set by two external resistors and one
capacitor. The use of TI's LMCMOS process extends
both the frequency range and the low supply
capability.
1
•
•
•
•
•
•
•
•
Industry's Fastest Astable Frequency of 3 MHz
Available in Industry's Smallest 8-Bump DSBGA
Package (1.43mm × 1.41mm)
Less Than 1 mW Typical Power Dissipation at 5 V
Supply
1.5 V Supply Operating Voltage Ensured
Output Fully Compatible With TTL and CMOS
Logic at 5 V Supply
Tested to −10 mA, 50 mA Output Current Levels
Reduced Supply Current Spikes During Output
Transitions
Extremely Low Reset, Trigger, and Threshold
Currents
Excellent Temperature Stability
Pin-for-Pin Compatible With 555 Series of Timers
Device Information(1)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
2 Applications
SOIC (8)
4.90 mm × 3.91 mm
•
•
•
•
•
•
•
VSSOP (8)
3.00 mm × 3.00 mm
PDIP (8)
9.81 mm × 6.35 mm
DSBGA (8)
1.43 mm × 1.41 mm
Precision Timing
Pulse Generation
Sequential Timing
Time Delay Generation
Pulse Width Modulation
Pulse Position Modulation
Linear Ramp Generators
Pulse Width Modulator
LMC555
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Pulse Width Modulator Waveform:
Top Waveform - Modulation
Bottom Waveform - Output Voltage
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.
LMC555
SNAS558M – FEBRUARY 2000 – REVISED JULY 2016
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
4
4
4
4
5
Parameter Measurement Information .................. 6
Detailed Description .............................................. 7
8.1
8.2
8.3
8.4
9
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information .................................................
Electrical Characteristics...........................................
Overview ...................................................................
Functional Block Diagram .........................................
Feature Description...................................................
Device Functional Modes..........................................
7
7
7
8
Application and Implementation ........................ 12
9.1
9.2
9.3
9.4
9.5
9.6
Application Information............................................
Typical Application .................................................
Frequency Divider ...................................................
Pulse Width Modulator ............................................
Pulse Position Modulator ........................................
50% Duty Cycle Oscillator ......................................
12
12
14
14
15
16
10 Power Supply Recommendations ..................... 17
11 Layout................................................................... 17
11.1 Layout Guidelines ................................................. 17
11.2 Layout Example .................................................... 17
12 Device and Documentation Support ................. 18
12.1
12.2
12.3
12.4
12.5
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
18
18
18
18
18
13 Mechanical, Packaging, and Orderable
Information ........................................................... 18
4 Revision History
Changes from Revision L (February 2016) to Revision M
Page
•
Changed order of Features list. ............................................................................................................................................. 1
•
Changed stable to astable - typo. .......................................................................................................................................... 1
•
Changed stable to astable - typo. .......................................................................................................................................... 7
•
Changed beings to begins typo. ............................................................................................................................................. 8
•
Changed typo LM555 to LMC555. ...................................................................................................................................... 12
•
Changed typo LM555 to LMC555. ...................................................................................................................................... 12
•
Added additional applications. ............................................................................................................................................. 14
Changes from Revision K (January 2015) to Revision L
•
Changed typo - temp range from 185 to 85 .......................................................................................................................... 4
Changes from Revision J (March 2013) to Revision K
•
2
Page
Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional
Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1
Changes from Revision I (March 2013) to Revision J
•
Page
Page
Changed layout of National Semiconductor Data Sheet to TI format ................................................................................. 17
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SNAS558M – FEBRUARY 2000 – REVISED JULY 2016
5 Pin Configuration and Functions
D, DGK, and P Packages
8-Pin SOIC, VSSOP, and PDIP
(Top View)
YPB Package
8-Pin DSBGA
(Top View)
Pin Functions
PIN
SOIC, VSSOP, and
PDIP NO.
DSBGA NO. NAME
I/O
DESCRIPTION
1
A3
GND
O
Ground reference voltage
2
B3
Trigger
I
Responsible for transition of the flip-flop from set to reset. The output of the
timer depends on the amplitude of the external trigger pulse applied to this pin
3
C3
Output
O
Output driven waveform
4
C2
Reset
I
Negative pulse applied to this pin to disable or reset the timer. When not used
for reset purposes, it should be connected to VCC to avoid false triggering
5
C1
Control
Voltage
I
Control voltage controls the threshold and trigger levels. It determines the pulse
width of the output waveform. An external voltage applied to this pin can also
be used to modulate the output waveform
6
B1
Threshold
I
Compares the voltage applied to the terminal with a reference voltage of 2/3
Vcc. The amplitude of voltage applied to this terminal is responsible for the set
state of the flip-flop.
7
A1
Discharge
I
Open collector output which discharges a capacitor between intervals (in phase
with output). It toggles the output from high to low when voltage reaches 2/3 of
the supply voltage
8
A2
V+
I
Supply voltage with respect to GND
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6 Specifications
6.1 Absolute Maximum Ratings
Over operating free-air temperature range, unless otherwise noted. (1) (2) (3)
MIN
MAX
UNIT
15
V
(V+) + 0.3
V
Supply
Voltage
Input
Curent
–0.3
Output
15
V
Output
100
mA
150
°C
Storage temperature, Tstg
(1)
(2)
(3)
–65
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
See AN-1112 (SNVA009) for DSBGA considerations.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/Distributors for availability and specifications.
6.2 ESD Ratings
V(ESD)
(1)
Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
VALUE
UNIT
±1500
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
Temperature Range
Maximum Allowable Power Dissipation
at 25°C
LMC555IM
−40
LMC555CM/MM/N/TP
−40
NOM
MAX
UNIT
125
°C
85
°C
PDIP-8
1126
mW
SOIC-8
740
mW
VSSOP-8
555
mW
568
mW
8-bump DSBGA
6.4 Thermal Information
LMC555
THERMAL METRIC (1)
RθJA
(1)
4
Junction-to-ambient thermal resistance
SOIC
VSSOP
PDIP
8-BUMP DSBGA
8 PINS
8 PINS
8 PINS
8 PINS
169
225
111
220
UNIT
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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6.5 Electrical Characteristics
Test Circuit, T = 25°C, all switches open, RESET to VS unless otherwise noted (1)
PARAMETER
IS
Supply Current
VCTRL
Control Voltage
TEST CONDITIONS
MIN
VS = 1.5 V
VS = 5 V
VS = 12 V
VS = 1.5 V
VS = 5 V
VS = 12 V
0.8
2.9
7.4
TYP
MAX
UNIT
50
100
150
150
250
400
µA
1.0
3.3
8.0
1.2
3.8
8.6
V
VDIS
Discharge Saturation Voltage
VS = 1.5 V, IDIS = 1 mA
VS = 5 V, IDIS = 10 mA
75
150
150
300
mV
VOL
Output Voltage (Low)
VS = 1.5 V, IO = 1 mA
VS = 5 V, IO = 8 mA
VS = 12 V, IO = 50 mA
0.2
0.3
1.0
0.4
0.6
2.0
V
Output Voltage
(High)
VS = 1.5 V, IO = −0.25 mA
VS = 5 V, IO = −2 mA
VS = 12 V, IO = −10 mA
1.0
4.4
10.5
1.25
4.7
11.3
VTRIG
Trigger Voltage
VS = 1.5V
VS = 12V
0.4
3.7
0.5
4.0
ITRIG
Trigger Current
VS = 5V
VRES
Reset Voltage
VS = 1.5 V
VS = 12 V
0.4
0.4
0.7
0.75
IRES
Reset Current
VS = 5 V
10
ITHRESH
Threshold Current
VS = 5 V
10
IDIS
Discharge Leakage
VS = 12 V
1.0
100
t
Timing Accuracy
SW 2, 4 Closed
VS = 1.5 V
VS = 5 V
VS = 12 V
1.1
1.1
1.1
1.25
1.20
1.25
VOH
V
0.6
4.3
10
(2)
0.9
1.0
1.0
V
pA
1.0
1.1
V
pA
pA
nA
ms
Δt/ΔVS
Timing Shift with Supply
VS = 5V ± 1 V
Δt/ΔT
Timing Shift with Temperature
VS = 5 V
fA
Astable Frequency
SW 1, 3 Closed, VS = 12 V
fMAX
Maximum Frequency
Max. Freq. Test Circuit, VS = 5 V
3.0
MHz
tR, tF
Output Rise and
Fall Times
Max. Freq. Test Circuit
VS = 5V, CL = 10 pF
15
ns
tPD
Trigger Propagation Delay
VS = 5 V, Measure Delay
from Trigger to Output
100
ns
(1)
(2)
4.0
0.3%
V
75
ppm/°C
4.8
5.6
kHz
All voltages are measured with respect to the ground pin, unless otherwise specified.
If the RESET pin is to be used at temperatures of −20°C and below VS is required to be 2.0 V or greater.
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7 Parameter Measurement Information
For device pinout, see Pin Configuration and Functions.
Figure 1. Test Circuit
6
For device pinout, see Pin Configuration and Functions.
Figure 2. Maximum Frequency Test Circuit
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8 Detailed Description
8.1 Overview
The LMC555 is a CMOS version of the industry standard 555 series general-purpose timers. In addition to the
standard package (SOIC, VSSSOP, and PDIP) the LMC555 is also available in a chip-sized package (8-bump
DSBGA) using TI’s DSBGA package technology. The LMC555 offers the same capability of generating accurate
time delays and 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 astable mode, the oscillation frequency and duty cycle are accurately set by two external resistors and one
capacitor. The use of TI’s LMCMOS process extends both the frequency range and the low supply capability.
The LMC555 is available in an 8-pin PDIP, SOIC, VSSOP, and 8-bump DSBGA package.
8.2 Functional Block Diagram
8.3 Feature Description
8.3.1 Low-Power Dissipation
The LMC555 offers the same capability of generating accurate time delays and frequencies as the LM555 but
with much lower power dissipation. A power dissipation of less than 0.2 mW can be achieved with a 1.5-V
operating supply voltage and less than 1 mW with a 5-V operating supply voltage. The use of TI’s LMCMOS
process allows this low supply current and voltage capability. Reduced supply current spikes during output
transitions and extremely low reset, trigger and threshold currents also provide low power dissipation advantages
with the LMC555.
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Feature Description (continued)
8.3.2 Various Packages and Compatibility
There are various packages available for use of the LMC555. In addition to the standard package (8-pin SOIC,
VSSOP, and PDIP, the LMC555 is also available in a chip-sized package (8-bump DSBGA). The PDIP, SOIC,
and VSSOP packages for the LMC555 are pin-for-pin compatible with the 555 series of timers
(NE555/SE555/LM555) allowing flexibility in design and unnecessary modifications to PCB schematics and
layouts.
8.3.3 Operates in Both Astable and Monostable Mode
The LMC555 can operate in both astable and monostable mode depending on the application requirements.
• Monostable mode: The LMC555 timer acts as a “one-shot” pulse generator. The pulse begins when the
LMC555 timer receives a signal at the trigger input that falls below a 1/3 of the voltage supply. The width of
the output pulse is determined by the time constant of an RC network. The output pulse ends when the
voltage on the capacitor equals 2/3 of the supply voltage. The output pulse width can be extended or
shortened depending on the application by adjusting the R and C values.
• Astable (free-running) mode: The LMC555 timer can operate as an oscillator and puts out a continuous
stream of rectangular pulses having a specified frequency. The frequency of the pulse stream depends on the
values of RA, RB, and C.
8.4 Device Functional Modes
8.4.1 Monostable Operation
In this mode of operation, the timer functions as a one-shot (Figure 3). The external capacitor is initially held
discharged by internal circuitry. Upon application of a negative trigger pulse of less than 1/3 VS to the Trigger
terminal, the flip-flop is set which both releases the short circuit across the capacitor and drives the output high.
Figure 3. Monostable (One-Shot)
The voltage across the capacitor then increases exponentially for a period of tH = 1.1 RAC, which is also the time
that the output stays high, at the end of which time the voltage equals 2/3 VS. The comparator then resets the
flip-flop which in turn discharges the capacitor and drives the output to its low state. Figure 4 shows the
waveforms generated in this mode of operation. Because the charge and the threshold level of the comparator
are both directly proportional to supply voltage, the timing internal is independent of supply.
8
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Device Functional Modes (continued)
VCC = 5 V
TIME = 0.1 ms/Div.
RA = 9.1 kΩ
C = 0.01 µF
Top Trace: Input 5 V/Div.
Middle Trace: Output 5 V/Div.
Bottom Trace: Capacitor Voltage 2 V/Div.
Figure 4. Monostable Waveforms
Reset overrides Trigger, which can override threshold. Therefore the trigger pulse must be shorter than the
desired tH. The minimum pulse width for the Trigger is 20 ns, and it is 400 ns for the Reset. During the timing
cycle when the output is high, the further application of a trigger pulse will not effect the circuit so long as the
trigger input is returned high at least 10 µs before the end of the timing interval. However the circuit can be reset
during this time by the application of a negative pulse to the reset terminal. The output will then remain in the low
state until a trigger pulse is again applied.
When the reset function is not use, it is recommended that it be connected to V+ to avoid any possibility of false
triggering. Figure 5 is a nomograph for easy determination of RC values for various time delays.
NOTE
In monstable operation, the trigger should be driven high before the end of timing cycle.
Figure 5. Time Delay
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Device Functional Modes (continued)
8.4.2 Astable Operation
If the circuit is connected as shown in Figure 6 (Trigger and Threshold terminals connected together) it will
trigger itself and free run as a multivibrator. The external capacitor charges through RA + RB and discharges
through RB. Thus the duty cycle may be precisely set by the ratio of these two resistors.
Figure 6. Astable (Variable Duty Cycle Oscillator)
In this mode of operation, the capacitor charges and discharges between 1/3 VS and 2/3 VS. As in the triggered
mode, the charge and discharge times, and therefore the frequency are independent of the supply voltage.
Figure 7 shows the waveform generated in this mode of operation.
VCC = 5 V
TIME = 20 µs/Div.
RA = 3.9 kΩ
RB = 9 kΩ
C = 0.01 µF
Top Trace: Output 5 V/Div.
Bottom Trace: Capacitor Voltage 1 V/Div.
Figure 7. Astable Waveforms
The charge time (output high) is given by
t1 = 0.693 (RA + RB)C
(1)
And the discharge time (output low) by:
t2 = 0.693 (RB)C
(2)
Thus the total period is:
T = t1 + t2 = 0.693 (RA + 2RB)C
(3)
The frequency of oscillation is:
(4)
Figure 8 may be used for quick determination of these RC Values. The duty cycle, as a fraction of total period
that the output is low, is:
D=
10
RB
RA + 2RB
(5)
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Device Functional Modes (continued)
Figure 8. Free-Running Frequency
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9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
9.1 Application Information
The LMC555 timer can be used a various configurations, but the most commonly used configuration is in
monostable mode. A typical application for the LMC555 timer in monostable mode is to turn on an LED for a
specific time duration. A pushbutton is used as the trigger to output a high pulse when trigger pin is pulsed low.
This simple application can be modified to fit any application requirement.
9.2 Typical Application
Figure 9 shows the schematic of the LM555 that flashes an LED in monostable mode.
Figure 9. Schematic of Monostable Mode to Flash an LED
9.2.1 Design Requirements
The main design requirement for this application requires calculating the duration of time for which the output
stays high. The duration of time is dependent on the R and C values (as shown in monostable figure) and can be
calculated by: t= 1.1*R*C seconds.
t = 1.1 × R × C
12
(6)
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Typical Application (continued)
9.2.2 Detailed Design Procedure
To allow the LED to flash on for a noticeable amount of time, a 5-second time delay was chosen for this
application. By using the equation:
t = 1.1 × R × C seconds
where
•
RC equals 4.545
(7)
If R is chosen as 100 kΩ, C = 45.4 µF. The values of R = 100 kΩ and C = 47 µF was chosen based on standard
values of resistors and capacitors.
A momentary push button switch connected to ground is connected to the trigger input with a 10-kΩ current
limiting resistor pull up to the supply voltage. When the push button is pressed, the trigger pin goes to GND. An
LED is connected to the output pin with a current limiting resistor in series from the output of the LMC555 to
GND. The reset pin is not used and was connected to the supply voltage.
9.2.3 Application Curve
The data shown in Figure 10 was collected with the circuit used in the typical applications section. The LM555
was configured in the monostable mode with a time delay of 5.17 s. The waveforms correspond to:
• Top Waveform (Blue) – Capacitor voltage
• Middle Waveform (Purple) – Trigger
• Bottom Waveform (Green) – Output
As the trigger pin pulses low, the capacitor voltage starts charging and the output goes high. The output goes low
as soon as the capacitor voltage reaches 2/3 of the supply voltage, which is the time delay set by the R and C
value. For this example, the time delay is 5.17 seconds.
Figure 10. Trigger, Capacitor Voltage, and Output Waveforms in Monostable Mode
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9.3 Frequency Divider
The monostable circuit of Figure 11 can be used as a frequency divider by adjusting the length of the timing
cycle. Figure 12 shows the waveforms generated in a divide by three circuit.
Figure 11. Monostable (One-Shot)
9.3.1 Design Requirements
Design a frequency divider by adjusting the length of the timing cycle.
9.3.2 Application Curve
Figure 12. Frequency Divider Waveforms
9.4 Pulse Width Modulator
When the timer is connected in the monostable mode and triggered with a continuous pulse train, the output
pulse width can be modulated by a signal applied to the control voltage terminal. Figure 13 shows the circuit, and
in Figure 14 are some waveform examples.
Figure 13. Pulse Width Modulator
9.4.1 Design Requirements
Modulator the output pulse width by the signal applied to the control voltage terminal.
14
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Pulse Width Modulator (continued)
9.4.2 Application Curve
Figure 14. Pulse Width Modulator Waveforms
9.5 Pulse Position Modulator
This application uses the timer connected for astable operation, as in Figure 15, with a modulating signal again
applied to the control voltage terminal. The pulse position varies with the modulating signal, since the threshold
voltage and hence the time delay is varied. Figure 16 shows the waveforms generated for a triangle wave
modulation signal.
Figure 15. Pulse Position Modulator
9.5.1 Design Requirements
Using astable operation vary the pulse position with a modulating signal applied to the control voltage terminal.
9.5.2 Application Curve
Figure 16. Pulse Position Modulator Waveforms
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9.6 50% Duty Cycle Oscillator
The frequency of oscillation is:
f = 1/(1.4 RCC)
(8)
Figure 17. 50% Duty Cycle Oscillator
9.6.1 Design Requirements
An oscillator with a 50% duty cycle output.
16
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10 Power Supply Recommendations
The LM555 requires a voltage supply within 1.5 V to 15 V. Adequate power supply bypassing is necessary to
protect associated circuitry. Minimum recommended is 0.1 μF in parallel with 1-μF electrolytic. Place the bypass
capacitors as close as possible to the LM555 and minimize the trace length.
11 Layout
11.1 Layout Guidelines
Standard PCB rules apply to routing the LMC555. The 0.1 µF in parallel with a 1-µF electrolytic capacitor should
be as close as possible to the LMC555. The capacitor used for the time delay should also be placed as close to
the discharge pin. A ground plane on the bottom layer can be used to provide better noise immunity and signal
integrity.
11.2 Layout Example
The figure below is the basic layout for various applications.
• C1 – based on time delay calculations
• C2 – 0.01 µF bypass capacitor for control voltage pin
• C3 – 0.1 µF bypass ceramic capacitor
• C4 – 1-µF electrolytic bypass capacitor
• R1 – based on time delay calculations
• U1 – LMC555
Figure 18. PCB Layout
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12 Device and Documentation Support
12.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
12.2 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
12.3 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
12.4 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.5 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
18
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Copyright © 2000–2016, Texas Instruments Incorporated
Product Folder Links: LMC555
PACKAGE OPTION ADDENDUM
www.ti.com
27-May-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
LMC555CM
NRND
SOIC
D
8
95
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-40 to 85
LMC
555CM
LMC555CM/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LMC
555CM
LMC555CMM
NRND
VSSOP
DGK
8
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 85
ZC5
LMC555CMM/NOPB
ACTIVE
VSSOP
DGK
8
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
ZC5
LMC555CMMX
NRND
VSSOP
DGK
8
3500
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 85
ZC5
LMC555CMMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
ZC5
LMC555CMX
NRND
SOIC
D
8
2500
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-40 to 85
LMC
555CM
LMC555CMX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LMC
555CM
Samples
LMC555CN/NOPB
ACTIVE
PDIP
P
8
40
RoHS & Green
NIPDAU
Level-1-NA-UNLIM
-40 to 85
LMC
555CN
Samples
LMC555CTP/NOPB
ACTIVE
DSBGA
YPB
8
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
F
02
Samples
LMC555CTPX/NOPB
ACTIVE
DSBGA
YPB
8
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
F
02
Samples
LMC555IM/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMC
555IM
Samples
LMC555IMX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMC
555IM
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
Addendum-Page 1
Samples
Samples
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
27-May-2022
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of