Pulse Generators. Any of the following calculations may be asked in the midterms/exam.

Transcription

1 ulse Generaors ny of he following calculaions may be asked in he miderms/exam.. a) capacior of wha capaciance forms an RC circui of s ime consan wih a 0 MΩ resisor? b) Wha percenage of he iniial volage will remain afer seconds beween he plaes of he capacior when his RC circui is discharged?. The ime consan of an RC circui is 0.6 seconds. a) To wha volage will he capacior be charged in s if he charging volage is 00 V? b) In wha ime will he capacior discharge o he half of he calculaed volage? 3. To wha volage should he 0 μf capacior of a defibrillaor be charged so ha he energy of he defibrillaing pulse is 60 J. 4. Wha is he pulse duraion of a monosable mulivibraor, if he ime consan of he swich circui is 5 ms and he rigger swich volage is level is 0/? 5. By wha facor does he energy of a capacior change if i is charged o double volage? 6. To how many imes greaer volage should a capacior be loaded so ha is energy is doubled? 7. smaller and a bigger capacior is loaded o he same volage. The capaciance of he bigger capacior is wice as much as ha of he smaller one. How many imes greaer is he energy sored in i? 8. The duraion of he square pulse of a pacemaker is ms while is volage ampliude is 4 V. Give he energy of a pulse if he resisance of he simulaed area is 800 Ω. 9. The horizonal division of he oscilloscope shown in he figure is 500 ms/div while is verical division is mv/div. The resisance of he simulaed area is kω. Find a) he duraion of he acive and b) he passive sae, c) he ime period, d) he duy cycle ( space facor ), e) he frequency, f) he ampliude, and g) he energy of a pulse. h) Wha are he ime consans of he swich circuis if he swich volage is 0/0?

2 0. The horizonal division of he oscilloscope shown in he figure is 0 ms/div while is verical division is 0,5 V/DIV. The resisance of he simulaed area is 0,8 kω. Find a) he duraion of he acive and b) he passive sae, c) he ime period, d) he duy cycle, e) he frequency, f) he ampliude, and g) he energy of a pulse. h) Wha are he ime consans of he swich circuis if he swich volage is 0/5?. The swich circui for he acive sae of an asable mulivibraor consiss of a kω resisor and a μf capacior while ha of is passive sae consiss of a 0 kω resisor and a 00 μf capacior. The swich volage is 0/4 for boh saes; he pulse ampliude is V; he resisance of he simulaed area is,5 kω. Calculae a) he duraion of he acive sae and b) he passive sae, c) he ime period, d) he frequency, e) he duy cycle, and f) he energy of a pulse.. For how long does a pacemaker work if a single pulse carries 4 μc charge and i conains a 500 mh baery wih an efficiency of 40%? Be he average hear frequency 7/minue. 3. leas how many mh baery is required o operae a pacemaker for 0 years if he average curren during is,5 ms pulses is,6 m? The efficiency of he baery is 50%, and he average hear rae is 75/min. 4. The duraion of he acive sae of an asable mulivibraor is ms while ha of is passive sae is 8 ms. a) Find he duy cycle. b) Find he frequency. 5. The ime period of an asable mulivibraor is 0 ms, is duy cycle is 5%. Find he duraion of he passive sae. 6. The frequency of an asable mulivibraor is 0 Hz, is duy cycle is 0%. Find he duraion of he acive sae. 7. Wha is he maximum coun of a binary couner consising of eigh bisable mulivibraors? 8. leas how many bisable mulivibraors are needed o build a binary couner if he maximum coun we wan o regiser is one housand?

3 9. The graph below shows he inpu volage of a monosable mulivibraor as funcion of ime. The volage hreshold of he mulivibraor is V and i is sensiive only for he railing edge of he inpu volage signal. The duraion of he acive sae is 0.6 s, he volage of is acive sae is.5 V while ha of is passive sae is 0 V. lo he oupu volage as funcion of ime. 0. The graph below shows he inpu volage of a bisable mulivibraor as funcion of ime. The volage hreshold of he mulivibraor is V and i is sensiive only for he railing edge of he inpu volage signal. The volage of is acive sae is.5 V while ha of is passive sae is 0 V, he mulivibraor is iniially in he passive sae. lo he oupu volage as funcion of ime.

4 Formulæ I Δq = (elecric curren) Δ ΔE = Δφ = (volage) Δq R = (resisance) I ΔE = (power) Δ = I = = I R (elecric power) R el C EC = (energy sored in a capacior) = RC (ime consan of an RC- circui) = = e (volage of capacior during charging an RC- circui) = 0 e (volage of capacior during discharging an RC- circui) = T = + (ime period of an asable mulivibraor) MV f = (frequency) T D T = = (duy cycle or space facor ) MV +

5 Soluions. a) = RC C = R = s 0 7 Ω =07 F = 0.µF b) = =0 e = e = e s s = 0.35 =3.5% =0 $. a) = = e ' $ & ) =00V & e % ( % b) = =0 e s 0.6s = e =0! ln $ # & = " =0 % # = ln & =0 % $ ' ( = 0.6s ln # & % $ ( = 0.46s ' ' ) = 8.V ( EC 60J 3. EC = C = = = 4000V = 4kV 6 C 0 0 F = = 0 = 0 ms = = 0 e 5 4. e ms = e 5 ms = e 5 ln = 5ms 5 ms ln = = ms 5. =, consequenly: E ( ) C, = C E C, = C( ) = C( ) = 4 C( ) = 4E C,, ha is, i increases fourfold.

6 6. EC, = EC,, as well as EC EC = C = ; consequenly: C EC, = C EC, ( EC, ) EC, = = = =, ha is, i mus be charged o a square C C C roo wo imes greaer volage. 7. C = C, consequenly: E C, = C E C, = C = ( C ) = C = E C,, ha is, he energy sored in i is wice as much. 8. ( 4V ) el = = = 0. 0W R 800Ω ΔE 5 = ΔE = Δ = 0.0W 0.00s = 0 J = 0µ J Δ 9. a) = DIV 500ms / DIV = 500ms = 0. 5s b) = DIV 500ms / DIV = 500ms = 0. 5s c) T = + = 0.5s + = s MV d) D = = = 0.5 = 50% TMV s e) f = = = s Hz TMV s = f) =.5DIV mv / DIV =. 5mV (.005V ) 0 9 g) el = = = W R 000Ω ΔE 9 9 = ΔE = Δ = el = W =.56 0 J =. 56nJ Δ

7 h) Since he duraion of boh he acive and he passive sae is 0.5 s he ime consan will also be he same: 0 = = 0 e = 0 = = 0 = e 0 0 = e ln 0 = e ln 0 = = = = 0. 7s ln0 0. a) = 0.DIV 0ms / DIV = ms b) = 3.9DIV 0ms / DIV = 39ms c) T = + = 4 ms = 0. s MV 04 d) D = TMV = = 4.88% e) f = TMV = 4.39Hz f) = 4.DIV 0.5V / DIV =. V 3 g) el = = W R Δ E = = J el µ ms 39ms h) cive sae: = =. 43ms ; passive sae: = = 4. 3ms ln5 ln a) = R C = 000Ω 0 F = 0 s = ms = = 0 e = 0 = = 0 e 4 = ln 4 = ms ln 4 =. 386ms b) = s = 000ms = ln 4 = 000ms ln 4 = ms c) TMV = + = ms = s d) f = = = 0.7Hz TMV.38768s e) D = = 0.00 = 0.% T MV

8 f) el = =. 6mW R Δ E = =. J el µ 6. q pulse = 4 0 C q oal = 500 mh 40% = s 0.4 = 70C = qoal 70C 8 npulse = = q 4 0 C pulse min 60s pulse = = = s = n = s.8 0 =.5 0 s 4. pulse pulse 753 years Δq 6 3. I = q pulse = I Δ = s = 4 0 C Δ d h min pulses = 0 yr = yr d h min 6 8 qoal = qpulse npulse = 4 0 C = 578C qoal 578C qbaery = = = 356C = 877mh η 50% n pulse 8 pulses ms 4. a) D = = = 0. = 0% + ms + 8ms b) f = = = = = = 50 = 50Hz T + ms + 8ms 0ms 0.0s s MV 5. D = T MV 0.05 = 0ms = ms = ms T MV = + = TMV = 0 ms ms = 9ms 6. f = T MV T = = = 0. s MV f 0 s D = TMV = D TMV = 0 % 0.s = 0.0s = 0ms = = 55

9 n 8. = 000 n =00 n = log 00= To he railing edge of every over- he- hreshold volage pulse inpu (a s; 3. s; 8.4 s;.; 5 s; and 8.6 s) belongs a 0.6 s long acive sae. The railing edges a 6. s and 6.8 s belong o below- he- hreshold volage pulses so hey will no rigger a response.

10 0. To he railing edge of every over- he- hreshold volage pulse inpu (a s; 3. s; 8.4 s;.; 5 s; and 8.6 s) belongs a ransiion beween he acive and passive saes. The railing edges a 6. s and 6.8 s belong o below- he- hreshold volage pulses so hey will no rigger a response.