.LOWTURNOFFTIME .MAXIMUM OPERATING FREQUENCY .TIMING FROM MICROSECONDS TO HOURS .OPERATES IN BOTH ASTABLE AND .HIGH OUTPUT CURRENT CAN SOURCE OR

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1 NE SA- SE GENERAL PURPOSE SINGLE BIPOLAR TIMERS.LOWTURNOFFTIME.MAXIMUM OPERATING FREQUENY GREATER THAN 00kHz.TIMING FROM MIROSEONDS TO HOURS.OPERATES IN BOTH ASTABLE AND MONOSTABLE MODES.HIGH OUTPUT URRENT AN SOURE OR SINK 00mA.ADJUSTABLE DUTY YLE.TTL OMPATIBLE.TEMPERATURE STABILITY OF 0.00% PER o DESRIPTION The NEmonolithic timing circuit is a highly stable controller capableof producing accuratetime delays or oscillation. In the time delay mode of operation, the time is precisely controlled by one external resistor and capacitor.for a stableoperation as an oscillator, the free running frequency and the duty cycle are both accurately controlled with two external resistors and one capacitor. The circuit may be triggered and reset on falling waveforms, and the outputstructurecansourceorsinkupto00ma.the NE is available in plastic and ceramic minidip package and in a 8-lead micropackage and in metal can package version. N DIP8 (Plastic Package) ORDER ODES Part Number Temperature Range D SO8 (Plastic Micropackage) Package NE 0 o, 0 o SA 0 o,0 o SE o, o N D -0.TBL PIN ONNETIONS(top view) 8 -GND -Trigger -Output -Reset - ontrol voltage -Threshold -Discharge 8-V April 99 /0

2 NE/SA/SE BLOK DIAGRAM V + kω THRESHOLD ONTROL VOLTAGE OMP R DISHARGE FLIP-FLOP kω Q TRIGGER OMP S INHIBIT/ RESET OUT kω RESET S S EPS SHEMATI DIAGRAM V THRESHOLD OMPARATOR ONTROL VOLTAGE OUTPUT R.kΩ R 80Ω R.kΩ R R8 kω kω R.8kΩ Q Q Q Q8 Q9 Q9 Q0 Q R Q THRESHOLD TRIGGER RESET DISHARGE Q Q Q Q Q Q0 Q Q Q R9 kω Q R kω D Q R.kΩ Q8 Q R 00Ω.9kΩ D R 0Ω R.kΩ Q GND Q R 0kΩ R 00kΩ R 00kΩ TRIGGEROMPARATOR R0 kω FLIPFLOP -0.EPS ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit V cc Supply Voltage 8 V Toper Operating Free Air Temperature Range for NE for SA for SE 0to0 0to 0 to Tj Junction Temperature 0 T stg StorageTemperatureRange to 0 o o o -0.TBL /0

3 NE/SA/SE OPERATING ONDITIONS Symbol Parameter SE NE- SA Unit V SupplyVoltage.to8.to V V th,v trig,v cl,v reset Maximum InputVoltage V V V -0.TBL ELETRIAL HARATERISTIS Tamb=+ o,v=+vto+v(unlessotherwisespecified) Symbol I VL Vth Parameter Supplyurrent(R L )(-note) LowState V =+V V=+V HighState V=V Timing Error(monostable) (RA=kto 00kΩ,=0.µF) Initial Accuracy-(note ) Drift with Temperature Drift with Supply Voltage Timing Error(astable) (RA,RB=kΩto 00kΩ,=0.µF, V=+V) Initial Accuracy-(note ) Drift with Temperature Drift with Supply Voltage ontrol Voltage level V=+V V=+V Threshold Voltage V=+V V=+V SE NE- SA Min. Typ. Max. Min. Typ. Max Unit ma % ppm/ %/V % ppm/ %/V I th Thresholdurrent- (note) µa V trig TriggerVoltage V =+V V =+V.8. I trig Triggerurrent(V trig =0V) µa Vreset Reset Voltage-(note ) V I reset VOL VOH Reseturrent V reset =+0.V Vreset=0V Low Level Output Voltage V =+V, I O(sink) =0mA I O(sink) =0mA IO(sink) = 00mA IO(sink) = 00mA V=+V, IO(sink)=8mA IO(sink) = ma High Level Output Voltage V=+V, IO(source)= 00mA IO(source) = 00mA V=+V, IO(source)= 00mA Notes:. SupplycurrentwhenoutputishighistypicallymA less.. Testedat V =+VandV =+V.. ThiswilldeterminethemaximumvalueofRA +RBfor +Voperation themaxtotalisr=0mωandforvoperation, themaxtotalr=.mω V V V ma V V -0.TBL /0

4 NE/SA/SE ELETRIAL HARATERISTIS (continued) Symbol Parameter I dis(off) DischargePinLeakageurrent (outputhigh)(v dis =0V) V dis(sat) DischargepinSaturationVoltage (outputlow)-(note) V=+V,Idis=mA V=+V,Idis=.mA tr t f OutputRise Time Output Fall Time SE NE- SA Min. Typ. Max. Min. Typ. Max. Unit na toff Turn off Time-(note )(Vreset = V) µs Notes:. No protection against excessive Pin current is necessary, providing the package dissipation rating will not be exceeded.. Timemesauredfromapositivegoinginputpulsefrom 0to 0.8xVintothethresholdtothedrop fromhigh tolowofthe output trigger is tied to treshold. Figure : Minimum Pulse Width Required for Trigering mv Figure : Supply urrent versus Supply Voltage ns -0.EPS -0.EPS -0.EPS -0.TBL Figure : Delay Time versus Temperature Figure : Low Output Voltage versus Output Sink urrent -08.EPS /0

5 NE/SA/SE Figure : Low Output Voltage versus Output Sink urrent Figure : Low Output Voltage versus Output Sink urrent -.EPS -09.EPS -0.EPS Figure: HighOutputVoltageDropversus Output Figure 8: Delay Time versus Supply Voltage -.EPS -.EPS Figure 9: Propagation Delay versus Voltage Level of Trigger Value /0

6 NE/SA/SE APPLIATION INFORMATION MONOSTABLE OPERATION Inthemonostablemode,thetimerfunctionsasa one-shot. Referring to figure 0 the external capacitor is initially held discharged by a transistor inside the timer. Figure 0 Figure t=0.ms/div INPUT =.0V/div OUTPUT VOLTAGE =.0V/div V =tov Reset R 8 Trigger Output NE ontrol Voltage 0.0µF -.EPS APAITOR VOLTAGE =.0V/div R=9.kΩ,=0.0µF,R =kω L Figure -.EPS The circuit triggers on a negative-going input signal when the level reaches / Vcc. Once triggered, the circuitremains inthisstateuntiltheset timehas elapsed,evenifitistriggeredagainduringthisinterval. The duration of the output HIGH stateis given byt=.r andiseasilydeterminedby figure. Notice that since the charge rate and the threshold level of the comparator are both directly proportional to supply voltage, the timing interval is independent of supply. Applying a negativepulse simultaneously totheresetterminal(pin)andthetriggerterminal (pin ) during the timing cycle discharges the externalcapacitorandcausesthecycletostartover.the timingcyclenowstartsonthepositiveedgeofthe resetpulse.duringthetimetheresetpulseinapplied,theoutputisdriventoitslowstate. Whenanegativetriggerpulseisappliedtopin,the flip-flop is set, releasing the short circuit across the external capacitor and driving the output HIGH. The voltage across the capacitor increases exponentiallywiththetimeconstantτ=r.whenthevoltageacrossthecapacitorequals/v cc,thecomparatorresets the flip-flop which then discharge the capacitor rapidly and drivers the output to its LOW state. Figure shows the actual waveforms generatedin this mode of operation. WhenResetisnotused,it shouldbetiedhighto avoid any possibly or false triggering. (µf) Ω R =k 0kΩ 00kΩ MΩ 0MΩ (t d) µs µs ms ms ms s ASTABLE OPERATION Whenthecircuitisconnectedasshowninfigure (pin and connected)it triggers itself and free runs as a multivibrator. The external capacitor charges throughr andr anddischargesthroughr only. Thusthedutycyclemaybepreciselysetbytheratio of these two resistors. Intheastablemodeof operation, chargesand dischargesbetween/vccand/vcc.asinthe triggeredmode, the charge and discharge times and therefore frequency are independent of the supply voltage. -.EPS /0

7 NE/SA/SE Figure Figure : Free Running Frequency versus R, R and V =tov Figure Output 0.0µF ontrol Voltage Figure shows actual waveforms generatedin this mode of operation. Thechargetime(outputHIGH)isgivenby: t =0.9(R +R ) andthedischargetime(outputlow)by: t=0.9(r) ThusthetotalperiodTisgivenby: t=0.ms/div T=t+t=0.9(R+R) The frequency ofoscillation is them: f = T =. (R +R ) andmaybeeasilyfoundbyfigure. Thedutycycleisgivenby: R D = R +R OUTPUT VOLTAGE =.0V/div 8 NE R R -.EPS (µf) R +R 0k 00kΩ Ω MΩ = 0MΩ kω k 0k f o(hz) PULSE WIDTH MODULATOR When the timer is connected in the monostable mode and triggered with a continuous pulse train, theoutputpulsewidthcanbemodulatedbyasignal appliedtopin.figureshowsthecircuit. Figure : Pulse Width Modulator. Trigger Output NE 8 Modulation Input RA V -8.EPS -0.EPS APAITOR VOLTAGE =.0V/div R=R=.8kΩ,=0.µF,R =kω L -9.EPS /0

8 NE/SA/SE LINEAR RAMP When the pullup resistor, RA, in the monostable circuit is replaced by a constant current source, a linear ramp is generated. Figure shows a circuit configuration that will perform this function. Figure. Trigger Output NE 8 RE N0 or equiv. 0.0µF Figure 8 shows waveforms generator by the linear ramp. Thetimeintervalisgivenby: T = (/V R E (R + R ) R V ±V BE (R + R ) V BE =0.V Figure8:LinearRamp. R R V -.EPS 0% DUTY YLE OSILLATOR Fora0%dutycycletheresistorsRAandREmay beconnected as in figure9. The time preriod for the outputhighisthesameasprevious, t =0.9R A. Fortheoutputlowitist= [(R A R B ) (R A +R B )]Ln R B ±R A R B ±R A Thusthefrequencyofoscillationisf = t + t NotethatthiscircuitwillnotoscillateifR B isgreater Figure 9: 0% Duty ycle Oscillator. Out NE V 8 R B kω 0.0µF V R A kω 0.0µF than/rabecausethejunctionofraandrbcannotbringpindownto/vandtriggerthelower comparator. -.EPS ADDITIONAL INFORMATION Adequate power supply bypassing is necessary to protect associated circuitry. Minimum recommended is 0.µF in parallel with µf electrolytic. -.EPS V=V Time = 0µs/DIV R = kω R = 00kΩ RE =.kω =0.0µF Toptrace: inputv/div Middle trace: output V/DIV Bottom trace: output V/DIV Bottom trace: capacitor voltage V/DIV 8/0

9 a I NE/SA/SE PAKAGE MEHANIAL DATA 8 PINS-PLASTIDIPOR ERDIP e L b B B e E Z e Z D 8 F A b PM-DIP8.EPS Millimeters Inches Dimensions Min. Typ. Max. Min. Typ. Max. A. 0. a B b b D E e e e F. 00 i L Z DIP8.TBL 9/0

10 F NE/SA/SE PAKAGE MEHANIAL DATA 8 PINS- PLASTI MIROPAKAGE(SO) L c a a A b e s a b e E D M 8 PM-SO8.EPS Millimeters Inches Dimensions Min. Typ. Max. Min. Typ. Max. A a a. 0.0 a b b c o (typ.) D E e e F L M S 8 o (max.) SO8.TBL Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No licence is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publicationare subject to change without notice. This publication supersedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. 99 SGS-THOMSON Microelectronics- All Rights Reserved SGS-THOMSON Microelectronics GROUP OF OMPANIES Australia- Brazil-France- Germany-HongKong-Italy- Japan-Korea-Malaysia-Malta-Morocco- TheNetherlands Singapore-Spain-Sweden-Switzerland-Taiwan-Thailand-UnitedKingdom-U.S.A. ORDERODE: 0/0

..LOW TURN OFF TIME NE555 SA555 - SE555 GENERAL PURPOSE SINGLE BIPOLAR TIMERS. MAXIMUM OPERATING FREQUENCY GREATER THAN 500kHz

..LOW TURN OFF TIME NE555 SA555 - SE555 GENERAL PURPOSE SINGLE BIPOLAR TIMERS. MAXIMUM OPERATING FREQUENCY GREATER THAN 500kHz NE SA - SE GENERAL PURPOSE SINGLE BIPOLAR TIMERS..LOW TURN OFF TIME MAXIMUM OPERATING FREQUENCY GREATER THAN 00kHz. TIMING FROM MICROSECONDS TO HOURS. OPERATES IN BOTH ASTABLE AND MONOSTABLE MODES HIGH