Ngā Tauira Pātai Kōrero mō te Transistor
He wāhanga hiko taketake ngā transistors e whai wāhi nui ana ki roto i te nuinga o ngā taputapu hiko hou. Hei pana me te whakakaha tohu, ka taea e ngā transistors ngā hangarau matatau pēnei i ngā rorohiko, waea pūkoro, me te maha atu o ngā taputapu. I roto i tēnei tuhinga, ka hipokina e mātou ētahi tauira me ā rātou otinga hei āwhina i a mātou ki te mārama ake ki te mahi a ngā transistors.
1. Whakataki ki ngā Pūwhakawhiti
I mua i te urunga atu ki ngā tauira raruraru, me kōrero tātou mō ngā transistors anō. Ko te transistor he wāhanga haurua-ira e toru ngā paparanga o ngā rauemi rerekē, e mōhiotia whānuitia ana ko NPN, ko PNP rānei, i runga i te tāpiritanga o te rauemi haurua-ira. E toru ōna pito: Pūtake (B), Kaiwhakaputa (E), me te Kaikohi (C).
Ngā momo transistors
– Pūhiko NPN: He momo pūhiko kei waenganui i ngā paparanga momo-N e rua te paparanga turanga.
– Pūwhakawhiti PNP: He momo pūwhakawhiti kei waenganui i ngā paparanga momo-P e rua te paparanga turanga.
He rite tonu te mahi a ēnei momo transistors e rua, engari he rerekē te ahunga o te iahiko me te polarity o te pānga.
Mahi Pūwhakawhiti
– Hei Pātene: Ka taea te whakamahi i ngā transistor hei tahuri, hei whakaweto rānei i te iahiko i roto i tētahi ara iahiko.
– Hei whakakaha: Ka taea e ngā transistors te whakakaha i ngā tohu tāuru iti ki ngā putanga nui ake.
2. Ngā Tauira Pātai me te Kōrero
Pātai 1: Whirihoranga Pūtake Whānui i runga i te Pūwhakawhiti NPN
Pātai: He 5 mA te iahiko tuku (IE) o tētahi transistor NPN me te whirihoranga turanga noa, ā, he 4.9 mA te iahiko kohikohi (IC). Whakatauhia te iahiko turanga (IB) me te tawhā α (alpha) o te transistor.
Kōrero:
– E mōhiotia ana:
– Te au tuku (IE) = 5 mA
– Iahiko kaikohi (IC) = 4.9 mA
– Pātai: Te au turanga (IB) me te tawhā α.
1. Te Tātai i te Ia Pūtake:
Ka whiwhihia te iahiko turanga mai i te whārite:
\[
I_E = I_B + I_C
\]
Nō reira,
\[
I_B = I_E – I_C = 5 \kākau {mA} – 4.9 \kākau {mA} = 0.1 \kākau {mA}
\]
2. Te Tātai i te Tawhā α:
Ko te tawhā α (alpha) ko te ōwehenga i waenga i te iahiko kohikohi me te iahiko tuku:
\[
\ārepa = \frac{I_C}{I_E} = \frac{4.9 \text{ mA}}{5 \text{ mA}} = 0.98
\]
Nō reira, ko te iahiko turanga (IB) he 0.1 mA, ā, ko te uara o te tawhā α he 0.98.
Pātai 2: Whirihoranga Kaituku Noa i runga i te Pūhiko NPN
Pātai: He 20 µA te iahiko turanga (IB) o tētahi transistor NPN, ā, he 100 te pikinga iahiko turanga (β). Tātaihia te iahiko kohikohi (IC) me te iahiko kaituku (IE).
Kōrero:
– E mōhiotia ana:
– Iahiko turanga (IB) = 20 µA
– Te pikinga o te au turanga (β) = 100
– Pātai: Te au kaikohi (IC) me te au tuku (IE).
1. Te Tātai i te Ia Kohikohi:
Ka whiwhihia te iahiko kohikohi mai i te whārite:
\[
I_C = \beta \times I_B = 100 \times 20 \text{ µA} = 2000 \text{ µA} = 2 \text{ mA}
\]
2. Te Tātai i te Ia Tuku:
Ka whiwhihia te iahiko tuku mai i te whārite:
\[
I_E = I_B + I_C = 20 \text{ µA} + 2000 \text{ µA} = 2020 \text{ µA} = 2.02 \text{ mA}
\]
Nō reira, ko te iahiko kohikohi (IC) he 2 mA, ā, ko te iahiko tuku (IE) he 2.02 mA.
Raru 3: Ara Whakakaha Transistor
Pātai: I roto i tētahi ara iahiko whakakaha transistor NPN, ko te ngaohiko turanga-kaituku (V_BE) he 0.7V, ko te ngaohiko kaikohi-kaituku (V_CE) he 5V, ā, ko te ngaohiko tuku hiko (V_CC) he 12V. Mena ko te ātete kaikohi (R_C) he 1 kΩ, ā, ko te iahiko turanga (IB) he 30 µA, tautuhia te iahiko kaikohi (IC) me te ngaohiko kaikohi (V_C).
Kōrero:
– E mōhiotia ana:
– Ngaohiko tuku-turanga (V_BE) = 0.7V
– Ngaohiko kaikohi-kaituku (V_CE) = 5V
– Pūtake ngaohiko (V_CC) = 12V
– Ātete kaikohi (R_C) = 1 kΩ = 1000 Ω
– Iahiko turanga (IB) = 30 µA
– Pātai: Te au kaikohi (IC) me te ngaohiko kaikohi (V_C).
1. Te Tātai i te Whiwhinga Au Pūtake (β):
Mai i te whirihoranga i runga ake nei, ka taea e tātou te whakaaro kei roto te transistor i te āhua hohe. Nō reira ka whakamahia e tātou:
\[
V_{CE} = V_C – V_E = 5V
\]
Nā te mea he iti te V_E i te whenua (ko te tikanga he 0V), kāti:
\[
V_C \tata ki te 5V
\]
2. Te Tātai i te Ia Kohikohi:
Ka taea te tatau i te iahiko kohikohi mā te whakamahi i te ture a Ohm:
\[
I_C = \frac{V_{CC} – V_C}{R_C}
\]
Te whakakapi i ngā uara:
\[
I_C = \frac{12V – 5V}{1000 Ω} = \frac{7V}{1000 Ω} = 7 \text{ mA}
\]
3. Te Tātai i te Ngaohiko Kaikohi:
Mā te whakamahi i te au i tatauhia:
\[
V_C = V_{CC} – (I_C \times R_C) = 12V – (7 \text{ mA} \times 1000 Ω) = 12V – 7V = 5V
\]
Nō reira, ko te iahiko kohikohi (IC) he 7 mA, ā, ko te ngaohiko kohikohi (V_C) he 5V.
Whakamutunga
He wāhanga matua ngā transistors i roto i ngā hikohiko, e mahi ana hei pana me hei whakakaha. Mā te mārama ki ngā tauira pēnei i te mea i runga ake nei, ka taea e tātou te whakamahi ngāwari i ngā transistors i roto i ngā momo ara iahiko. Ko te mārama ki ngā tawhā pēnei i te iahiko turanga, te iahiko kohikohi, te ngaohiko kohikohi-kaituku, me te whakanui iahiko turanga (β) he taahiraa matua i roto i te hoahoa me te tātari i ngā ara iahiko hiko. Ko te tumanako kua whai hua tēnei tuhinga ki te whakahōhonu ake i tō tātou mōhiotanga ki ngā transistors!
