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Details, datasheet, quote on part number:LMC555J
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| Part: | LMC555J |
| Category: | Timing Circuits => Timers => Timers and Oscillators |
| Description: | LMC555 - CMOS Timer, Package: Microsmd, Pin Nb=8 |
| Company: | National Semiconductor Corporation |
| Datasheet: | Download LMC555J datasheet File size : 325 kB |
| Request For quote: | Find where to buy LMC555J
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Datasheet text preview:
LMC555 CMOS Timer
March 2002
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 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 stable mode the oscillation frequency and duty cycle are accurately set by two external resistors and one capacitor. The use of National Semiconductor 's LMCMOSTM process extends both the frequency range and low supply capability.
Features
n n n n n n n n n n Less than 1 mW typical power dissipation at 5V supply 3 MHz astable frequency capability 1.5V supply operating voltage guaranteed Output fully compatible with TTL and CMOS logic at 5V 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 Available in 8 pin MSOP Package and 8-Bump micro SMD package
Block and Connection Diagrams
8-Pin SOIC, MSOP, and MDIP Packages 8-Bump micro SMD
DS008669-1
Top View Top View (Bump side down)
DS008669-9
Pulse Width Modulator
DS008669-15
DS008669-20
LMCMOSTM is a trademark of National Semiconductor Corp.
© 2002 National Semiconductor Corporation
DS008669
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LMC555
Ordering Information
Package Temperature Range Industrial -40°C to +85°C 8-LeadSmall Outline (SO) 8-Lead Mini Small Outline (MSOP) 8-Lead Molded Dip (MDIP) 8-Bump micro SMD micro SMD Demo Board LMC555CM LMC555CMX LMC555CMM LMC555CMMX LMC555CN LMC555CBP LMC555CBPX LMC555CBPEVAL LMC555CM LMC555CM ZC5 ZC5 LMC555CN F1 F1 N/A Rails 2.5k Units Tape and Reel 1k Units Tape and Reel 3.5k Units Tape and Reel Rails 250 Units Tape and Reel 3k Units Tape and Reel N/A Package Marking Transport Media NSC Drawing
M08A MUA08A N08E BPA08EFB N/A
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LMC555
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+ Input Voltages, VTRIG, VRES, VCTRL, VTHRESH Output Voltages, VO, VDIS Output Current IO, IDIS Storage Temperature Range Soldering Information MDIP Soldering (10 seconds) SOIC, MSOP Vapor Phase (60 sec) SOIC, MSOP Infrared (15 sec) 15V -0.3V to VS + 0.3V 15V 100 mA -65°C to +150°C 260°C 215°C 220°C
Operating Ratings(Notes 2, 3)
Termperature Range Thermal Resistance (JA) (Note 2) SO, 8-lead Small Outline MSOP, 8-lead Mini Small Outline MDIP, 8-lead Molded Dip 8-Bump micro SMD Maximum Allowable Power Dissipation @25°C MDIP-8 SO-8 MSOP-8 8 Bump micro SMD -40°C to +85°C 169°C/W 225°C/W 111°C/W 220°C/W
1126mW 740mW 555mW 568mW
Note: See AN-450 "Surface Mounting Methods and Their Effect on Product Reliability" for other methods of soldering surface mount devices.
Electrical Characteristics
Symbol IS Parameter Supply Current
(Notes 1, 2) Test Circuit, T = 25°C, all switches open, RESET to VS unless otherwise noted Conditions VS = 1.5V VS = 5V VS = 12V VS = 1.5V VS = 5V VS = 12V VS = 1.5V, IDIS = 1 mA VS = 5V, IDIS = 10 mA VS = 1.5V, IO = 1 mA VS = 5V, IO = 8 mA VS = 12V, IO = 50 mA VS = 1.5V, IO = -0.25 mA VS = 5V, IO = -2 mA VS = 12V, IO = -10 mA VS = 1.5V VS = 12V VS = 5V VS = 1.5V (Note 4) VS = 12V VS = 5V VS = 5V VS = 12V SW 2, 4 Closed VS = 1.5V VS = 5V VS = 12V VS = 5V ± 1V VS = 5V -40°C T +85°C SW 1, 3 Closed, VS = 12V Max. Freq. Test Circuit, VS = 5V Max. Freq. Test Circuit VS = 5V, CL = 10 pF 4.0 0.9 1.0 1.0 0.4 0.4 1.0 4.4 10.5 0.4 3.7 0.8 2.9 7.4 Min Typ 50 100 150 1.0 3.3 8.0 75 150 0.2 0.3 1.0 1.25 4.7 11.3 0.5 4.0 10 0.7 0.75 10 10 1.0 1.1 1.1 1.1 0.3 75 4.8 3.0 15 5.6 100 1.25 1.20 1.25 1.0 1.1 0.6 4.3 Max 150 250 400 1.2 3.8 8.6 150 300 0.4 0.6 2.0 Units (Limits) µA
VCTRL
Control Voltage
V
VDIS VOL
Discharge Saturation Voltage Output Voltage (Low)
mV
V
VOH
Output Voltage (High) Trigger Voltage Trigger Current Reset Voltage Reset Current Threshold Current Discharge Leakage Timing Accuracy
V
VTRIG ITRIG VRES IRES ITHRESH IDIS t
V pA V pA pA nA
ms
t/VS t/T fA fMAX tR, tF
Timing Shift with Supply Timing Shift with Temperature Astable Frequency Maximum Frequency Output Rise and Fall Times
%/V ppm/°C kHz MHz ns
3
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LMC555
Electrical Characteristics
Symbol tPD Parameter Trigger Propagation Delay
(Notes 1, 2) Test Circuit, T = 25°C, all switches open, RESET to VS unless otherwise noted (Continued) Conditions VS = 5V, Measure Delay from Trigger to Output Min Typ Max Units (Limits) ns
100
Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified. Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device performance. Note 3: See AN-450 for other methods of soldering surface mount devices, and also AN-1112 for micro SMD considerations. Note 4: If the RESET pin is to be used at temperatures of -20°C and below VS is required to be 2.0V or greater. Note 5: For device pinout please refer to table 1
Test Circuit (Note 5)
Maximum Frequency Test Circuit (Note 5)
DS008669-3 DS008669-2
TABLE 1. Package Pinout Names vs. Pin Function Pin Function GND Trigger Output Reset Control Voltage Threshold Discharge V
+
Package Pin numbers 8-Pin SO,MSOP, and MDIP 1 2 3 4 5 6 7 8 8-Bump micro SMD A3 B3 C3 C2 C1 B1 A1 A2
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LMC555
Application Info
MONOSTABLE OPERATION In this mode of operation, the timer functions as a one-shot (Figure 1). 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.
When the reset function is not use, it is recommended that it be connected to V+ to avoid any possibility of false triggering. Figure 3 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.
DS008669-11
DS008669-4
FIGURE 3. Time Delay ASTABLE OPERATION If the circuit is connected as shown in Figure 4 (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 1. 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 2 shows the waveforms generated in this mode of operation. Since the charge and the threshold level of the comparator are both directly proportional to supply voltage, the timing internal is independent of supply.
DS008669-5 DS008669-10
FIGURE 4. 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.
VCC = 5V TIME = 0.1 ms/Div. RA = 9.1k C = 0.01µF
Top Trace: Input 5V/Div. Middle Trace: Output 5V/Div. Bottom Trace: Capacitor Voltage 2V/Div.
FIGURE 2. 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 20ns, and it is 400ns 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 10µs 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.
Figure 5 shows the waveform generated in this mode of operation.
5
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