Te Reo o ADC me DAC: Ngā Kōrero Matua me ngā Paremata Mahi

Ka mahi ngā whakawhiti pūreretahi-ki-tīkanga (ADC) me ngā whakawhiti tīkanga-ki-pūreretahi (DAC) hei pākū ki waenganui i te ao pūreretahi, kei reira ngā pānga pono pērā i te oro, te pāmahana, me te pūngao e noho ana, me te ao tīkanga, kei reira ka tangohia me te penapena ngā pārongo. Ka whakamārama tēnei tuhinga i ngā kōrero ADC me DAC e tino mea ana i ngā pūnaha tūturu. Ko ia kupu he tūranga ki te pāna o te whakawhiti i ngā pānga pono i te ao, i ngā tono pērā i ngā pūnaha kōrero, te whakarōpū oro, ngā pūrere, me ngā rorohiko umanga.

Kātā

Te Reo o ADC me DAC i ngā Pūnaha Tūturu

Wā Tango

Ko te wā tango te wā e hiahiatia ana mō te capacitor sampling a te ADC ki te pākū, ki te whakarite ki te pūngao whakauru i muri i te huringa mai i te arai ki te pupuri. I te hoahoa ADC pono, ehara tēnei i te pānga anake—ka whakatau i te āhua o te uara i tangohia, mēnā he pono, he rerekē.

He mea nui tēnei i te mea kāhore e taea e te pūnaha te tango i ngā pānga e huri atu ana hei te wā tango, kāore e taea e te capacitor te whakatau i te pai, e whakaputa ana i ngā he whakawhiti. I ngā pūnaha tango raraunga tere, pēnā i te whakahaere motokā, i te tango RF, ko te wā tango kāore e taea te whakatutuki ka arai i te pānga ipurangi me te whakaata me ngā ākonga tūturu. Me pāngia e ngā kaihoahoa te wā tango ki te pānga pūngao e whai ake ana me te taux sampling hei pupuri i te tika.

Pānga

Ko te pānga he he tango e tupu ana ka tango i te pānga i raro i te reiti Nyquist. Ka pāngia ngā kōwae teitei ki ngā kōwae iti, e whakaputa ana i ngā pānga mōhiohio kāore e noho ana i te pūngao whakauru.

He mea tino nui tēnei i ngā pūnaha tūturu nāna i taea te kore e taea te whakatikatika i te wa e pānga ana. Hei tauira, i ngā pūnaha oro e whakaputa ana i ngā oro kāore e hiahiatia ana, i ngā pūnaha pūrere ka taea te whakaputa i ngā ine rerekē. No reira, me kī ā-naga ngā pānga anti-misrepresentation i mua i te ADC ki te tango i ngā pānga kei runga i te haurua o te taux tango.

Te Whakatakoto Hei Aro

Ko te whakatakoto hei aro te rerekētanga wā i waenganui i te pito taika o te taux tango me te wā tika e pānga ana te ADC ki te pānga whakauru.

I ngā pūnaha tūturu, ka tino pā te whakatakoto hei aro ina mēnā e ine ana i te pānga e huri ana e tere. Ahakoa te rahi o te whakatakoto, ka tērā pea ngā heā i waenganui i ngā aratau ki te pūnaha tārua, ka arai i te tatau tika o te wā i ngā tono pēnā i ngā oscilloscope, ngā rēhita kōrero.

Nehenehe Aperture

Ko te nehenehe aperture e pā ana ki ngā rerekētanga e joku ana i te wā tango. Kāore ke he huringa tautoko, ko te nehenehe e whakaatu ana i te whakanui i te wā i tango ai.

He tino nui tēnei i ngā pānga hohe, nāna i taea te whakanui i te hwgā, kāore e taea e te nehenene aperture te whakaheke i te SNR, e whakararu ana i te whakamōhiotanga e taea e te ADC hei te rahi i te mana.

Whakataurite Pūreretahi (Unipolar)

Ko te whakataurite pūreretahi i ngā ADC unipolar e pā ana ki ngā pūngao whakauru pātea whiwhi ki ngā uara digital, he paerewa mai i te 0 ki te rahi-takena.

Ka whakamahia whānuitia i ngā pūnaha pū-ā-reko, pērā i ngā pūrere i runga i te pūngao tiitiga. Ko te āheinga, kāore e taea te whakatakoto mēnā he pānga kino, e hiahiatia ana te huringa he pūnāwai, hei meka.

Pūnga Bipolar

Ka taea e te pānga bipōlar te pānga ki te ū me te rāhita ki te taiao paerewa (ka wātea te whenua, te rūnanga o ngā whakamahinga). He mea tino nui i ngā pūnaha rerekē, pēnā i te oro, i ngā pūrere īmēra, me ngā pūrere umanga nāna i te pupuri i ngā kōrero pūreretahi me ngā kōrero binge i rotorua ka waiho i ngā kupu tūpono.

Ngā Tūnaha Riko (CMR)

Ko te Whakaaturanga Moepu i te Kōmaka e pā ana ki te pai o te pūnaha rerekē ki te whāiti i ngā tohu pēnei i runga i ngā pūnaha e rua. I ngā pūnaha ADC whaihua, he mea nui te CMR teitei nāna i te mea ka tae te auau ki ngā rārangi tohu e rua i te kāinga (pērā i te EMI). Ko te ratio CMR teitei ka whakarite i te pātea kei te whakawhiti anake, me te piki ake i te tika i roto i ngā taiao ahumahi haumaru.

Whakaahua

Ko te whakaahua he tono tohu e kore e hiahia ana i waenganui i ngā hongere tata i roto i ngā pūnaha ADC/DAC maha-hongere. He mea nui i roto i ngā whakamahinga PCB teitei ka taea e ngā tohu auau te raru i ngā hongere tata. Ka whakaitihia tēnei te tika o te inenga i roto i ngā pūnaha pērā i ngā pūnaha sensa maha, ngā mixer oro, me ngā pokapu whakawhiti kōrero.

Te Hē Rerekē (DNL)

Ko te DNL e mehua ana te pehea e rerekē ana ia ia ki te paerewa 1 LSB akoranga. I ngā tikanga hei whakamahi, e whakatau ana i te pātea o te putanga ADC ka pātea rānei ka ngaro ngā waehere. Ko te DNL teitei ka whakakotahi te whakaritenga kāore e taea te whakapōturi i ngā pūnaha inenga taurangi pēnei i te taputapu mamati.

Te Whakauru Mamati

Ko te whakauru mamati he noise e puta ana i te putanga DAC nāna i te whakawhitinga mamati o roto. He mea nui tēnei i roto i ngā pūnaha tikanga-tahi nāna i te pātea ki ngā whakawhiti mamati e taea te whakauru ki te putanga analoga, e hanga ana i ngā spike e whakaiti ana i te puāwaitanga tohu, i ngā pūnaha oro me ngā pūnaha hanga waveform.

Te Whānuitanga Takatū

Ko te whānuitanga takatū te ratio i waenganui i te tohu iti rawa e taea te kite me te tohu toitoi e kore e raru. Ko te whānuitanga takatū teitei ka āhei te pūnaha ki te inenga i te tohu ngoikore i raro i te mana kaha, he mea nui i roto i te radar, te whakaahua rongoā, me te whakahaere oro.

Te Tau Tika o ngā Bit (ENOB)

Ko te ENOB e tohu ana i te whānuitanga tino e taea te whakamahi i ngā ADC i muri i te whakaarohia te noise me te rikiriki. Ahakoa kei te tohu te ADC i te 12, i te 16 bit, ko te ENOB pono ka iti iho te i te noho o te wera, te jitter, me te hē rerekē. Ka waihohia hei tohu i te mahinga hei pātea i te whānuitanga paerewa.

Te Utu Tika (RMS)

Ko te RMS (Root Mean Square) te uara DC e pā ana ki te tohu AC e whakaatu ana i te pūnaha mana. Ka whakamahia i roto i ngā pūnaha ADC/DAC ki te whakatau i te kaha tohu i roto i te hiko pūnaha, oro, me ngā pūnaha sensa.

Te Whānuitanga Mana Tūmau

E whakarite ana tēnei i te auau whakauru teitei ka taea e te ADC te whakahaere i te tohu whanui mutunga kāore e raru te rahi. He mea nui i ngā whakamahinga auau teitei nāna i te pātea ki te tere te mau, ka taea e ngā here o mua ana ka whakaiti i te whānuitanga e taea te whakamahi.

Te Hē Rahi Tūmau

Ko te hē rahi tūmau ko te rerekētanga i waenga i te putanga mau me te putanga tino. Ka pāngia tonu te tika o te tikanga pūranga i ngā pūnaha inenga me whakapāhinga i ngā whakamahinga ADC tika.

Te Hē Rahi Whakatakoto

Ko tēnei te hē whakamahinga huri i te katoa o te rārangi whakawhiti. Ka pāngia te tika o ngā whakaurunga tautuhi ki te putanga mamati ka whakatikahia e ngā kōwae calibration.

Te Hē Whakatakoto

Ko te hē whakatakoto e mehua ana te rerekētanga i te tawhiti i waenga i te putanga mau me te putanga tino. I ngā pūnaha pono, ka tipu tēnei ki te te tāhū i pa ngā inenga rerekē i ngā taumata whakauru katoa.

Te Pātūtanga Hē Whakatakoto

E whakaahua ana te pātūtanga hē whakatakoto i te pākū e huri ana ki te pāmahana. He mea nui i ngā taiao ahumahi e taea te pāhotanga huri i te whakakāori.

Te Ikā Hātepe

E whakarite ana te Ikā Hātepe e rua ngā pūnaha ADC ki te whakaputa i te mahi whakakaha rite. He mea hira i ngā pūnaha maha-hongere pērā i ngā pūnaha taapa me ngā pūnaha inenga sensa maha.

Te Rerekē Tīmata (INL)

E mehua ana te INL pehea ka rerekē te pūnaha whakawhiti ADC i te rārangi tika i muri i te tango i te hē o te offset me te hē whakauru. Ka pāngia ngā tika me te rerekē, ka waihohia hei āhuatanga tino mō te ADC tika.

Te Rikiriki Intermodulation (IMD)

Ka puta te IMD i ngā wā e pahemo ana ngā tohu maha nāna e mau te hē rerekē, e puta ana te wāhanga auau kāore e hiahia ana.

Te Bit Iti Rerekē (LSB)

Ko te LSB te tini o te huringa pūngao e pā ana ki te huringa ōkawa kotahi i te putanga mamati. Ka whakarite te tikanga tautuhi me te tuku wāhi ki te ADC ki te whakawhāiti i ngā huringa tohu iti.

Te Putanga Nīkau

Ko te nīkau whai pānga e mehua ana i te pūngao i te nīkau ka tapatahi ki te pākū i te puoro kāore ki te puna. Ka whai hua tēnei ki te whakapai ake i te tika whakahaere i roto i ngā pūnaha hiko mā te whakaiti i ngā ngaro pūngao i ngā wiring.

Te Huringa MSB

Ko te huihuinga pātere e tino pāngia ana i roto i te DAC ka huri te bit nui, e ko te tikanga ka tango i ngā glitch putanga.

Te Bit Nui (MSB)

Ko te bit tino teitei i roto i te tau pānuitia, e kawe ana i te nui o te tohatoha ki te uara putanga.

DAC Whakatipu

He DAC e whakamahi ana i te tohu analoga whakauru ki waho, e taea ai te huri i ngā tohu AC ki te mamati.

Te Auau Nyquist

Ko te teitei rōrahi ka taea te tango tika i runga i te kore ai, he rite ki te haurua o te rōrahi tango.

Hētautanga Offset

Ko te hētautanga offset e tohu ana i te hē i te taumata urupare kore e pā ana ki te whanonga putanga tino.

Hētautanga Offset Tūātea

Ko te rerekētanga e pā ana ki te hētautanga offset i whakatūria e te pāmahana i te taha o te wā.

Tēnā Tango

Te tango i runga i te rōrahi tino teitei ake i te rōrahi Nyquist hei whakapiki i te rerekētanga me te whakaiti i te haruru.

Whakamahia te Rarangi

Te rahi o te whakatairite o te wā i waenga i ngā kana ADC maha e ine ana i te tohu kotahi.

Te Tūātea Tukunga Pūweretia (PSRR)

Ko te āheinga o te huri hei whakaiti i te rerekētanga putanga nāna i tango i ngā huringa i te pāmahana pūwera.

Hētautanga Quantization

Ko te rerekētanga i waenga i te urupare analog tūturu me tana whakaaturanga pāngarau tata.

Te Ine Ratio

He tikanga ine e kākahu ana te pāmahana tohu hei āhuatanga ki te tohu urupare, e whakapiki ana i te tika i roto i ngā pūnaha rerekē.

Tūātea

Ko te tau o ngā pātene e whakamahia ana hei whakaatu i ngā tohu analog i roto i te mahi pāngarau. Ka whakapiki te tūātea i te tika.

Rōrahi Tango

Ko te tau o ngā tauira e mau ana i te hekona e ADC.

Te Ratio Tohu ki te Haruru (SNR)

Ko te ratio o te pūngao tohu ki te pūngao haruru i roto i te pūnaha.

SINAD

He āwhina mahi e waiho ana i ngā haruru me te rerekētanga e pā ana ki te tohu matua.

Tere Tīwhiri

Ko te tere maksimum ka taea e te pāmahana putanga te huri i te wā.

Rōrahi Tōrere Kōwae Iti

Ko te rōrahi rerekē e pā ana ki te rōrahi e whakamahi ana te huri i ngā tohu iti.

Te Rōrahi Tere-Haruru (SFDR)

Ko te rerekētanga i waenga i te tohu matua me te wāhanga ānā haruru nui.

Spike (Ngā Hiko Hōhonu)

Ko te hiko spike, he hiko e whakaaturia ana me ngā tāuhi te wā e pānga ana. E pā ana ki te tika o te hōkai i roto i ngā pūnaha putanga analog tino.

Huringa Mahi me te Pupuni

Ko tenei huringa e tango ana i te tohu analog ka pupuni ana i te wā e whakawhiti ana. Ka hiahia te ADC i te urupare pūmau i te wāhanga whakawhiti.

Haruru Taumata

Ko te haruru taumata he ānū i te wā e pānga ana te putanga ADC i waenga i ngā waehere tuhinga. E whakatau ana i te ahua o te putanga pāngarau e puta ana i te taha o ngā tau.

Te Rerekētanga Total Harmonic Distortion (THD)

E ine ana te THD i te ihirangi harmonic e whakaputahia ana e te rerekētanga nonlinear.

Under-Sampling

Ko te under-sampling e tango ana i raro i te Nyquist hei tātaritanga mō ngā tohu rōrahi teitei. Ka whakamahia i roto i ngā pūnaha RF e whai wāhi ana i ngā tohu band-pass.

Te Urupare Unipolar

Ko te urupare unipolar e pā ana ki ngā tohu e rerekē ana i roto i te rahi kotahi anake. Ka ngawari te hoahoa ADC engari ka whakamāori i te ngākau o te tohu.

Hētautanga Amplitude Rōrahi

Ko tenei he tāruatanga anō o te hētautanga offset i roto i ngā pūnaha unipolar, ka tohu i te hē i te taumata urupare kore. Ka pā hoki i te tika o ngā tohu iti.

Ngā Whakamāori Hēna o ngā Kupu ADC me DAC

• Te Tūātea vs te Tika Haumaru - Ko te tūātea e pā ana ki te tau o ngā pātene i roto i te huringa, i te wā e pā ana te tika ki te āhua kei te putanga ki te uara analog pono. Kaore te tūātea teitei e whakarite i te tika teitei, nā te haruru, te hē tūātea, te hē offset, me te rerekētanga nonlinear e pā ana ki te mahi.

• He Hē Te Hātehi SNR, SINAD, me THD - Ko te Ratio Tohu ki te Haruru (SNR) e titiro ana ki te haruru anake, i te wā e tāpiri ana te SINAD i te haruru me te hē. Ko te Total Harmonic Distortion (THD) e ine ana i te rerekētanga harmonic anake. Ki te tukua ēnei hei mea kotahi ko te mea he mārama hē i te kounga tohu.

• ENOB vs ADC Bit Tūātea - Te Tau Ōhākī Pūmanawa (ENOB) e tohu ana i te tūātea e whakamahia ana i raro i ngā tikanga haruru me te rerekētanga, i te wā ko te tūātea pātene ADC he teoretika maksimum. Ko te whakanui ngoikore i te mea e mōhiotia ana e rua ka puta i ngā whakaaro hē mō ngā mahi pūnaha.

• Rōrahi Tango vs te Rōrahi Kōwae - Ko te rōrahi tango e tohu ana i te whānuitanga i ngā tauira e tango ana, i te wā ko te rōrahi kōwae e tohu ana i te rōrahi o ngā rōrahi e taea te whakahaere tika. Ko te kore whakaaro ki te whakaritenga Nyquist ka awhina i te pākākano me te rerekētanga tohu.

• INL vs DNL Hē - Ko te Differential Nonlinearity (DNL) e pā ana ki te mahinga rahi i waenga i ngā waehere tuhinga e pā ana, i te wā ko te Integral Nonlinearity (INL) e ine ana i te rerekētanga katoa mai i te tira whakaritenga. Ko te whakanui i ēnei hei mea kotahi ka kite te padru hē i te ine tātironga whenua.

• Te Noho Kore i Te Pānga o ngā Haruru me te Rerekētanga Pānga - He maha ngā kaiwhakamahi e hiahia ana ki te hūmārika te whānuitanga pā, engari he pānga e pā ana ki te haruru pāmahana, haruru tango, jitter, me te rerekētanga nonlinear, ka pā katoa i ngā mahi.

• Tika vs Mahi Tino - Ko ngā tātaritanga tuhinga te nuinga e whakaatu ana i ngā tikanga tūmatanui, e mōhiotia ana i ngā tūmatanui hōu. I ngā tono tūturu, he rerekētanga i ngā mahi e pā ana ki te pāmahana, te rōrahi, ngā tikanga, me te hoahoa huringa.

Whakamutunga

Ko nga kupu i whakahuahia i runga i te whakarite ko te tikanga kāore e taea e te punaha te tango, te whakawhiti, me te koha i nga tohu i raro i nga kaupapa whakahaere pono. Ko te whakapakari i te kōrero ADC me DAC ka whakapai ake i te tika o te miihini, te noho pumau o te punaha, me te whaihua hoahoa. Ka taea hoki e nga miihini te aromātai i nga waahanga hei awhina i te tirohanga, te whakapai ake i te kanorau tohu, me te whakarite ka tutuki te mahi i te ao tūturu ki nga whakaritenga hoahoa.

Nga Paatai i Pātaihia i Ngā Wa [FAQ]

1. Me pehea e pā ana te aperture jitter ki te mahi ADC teitei te auau, ā, he aha te mea he mea nui atu i te pōkiri aperture i ngā tono RF?

Ka whakauru te aperture jitter i te āhuatanga wa ki te wāhi tango, e huri ana tēnā ki te haruru pūhiko i ngā auau input teitei. I roto i nga pūnaha RF me te tere, ko te pātea iti ka pai ake te whakaheke i te SNR, e noho ana hei mea nui atu i te pōkiri aperture tuohokohoko.

2. He aha te take e heke ana te ENOB i te pikinga o te auau input ahakoa kei te noho tonu te whakatauranga ADC?

Ka heke te ENOB nā te mea ka piki te haruru me te parahanga i te pikinga o nga auau input. Ko nga pānga pēnei i te jitter, te kore pātea, me nga herenga bandwidth e whakaheke ana i nga bubinga e taea te whakamahi ahakoa kei te noho tonu te whakatauranga physical.

3. Me pehea e pā ana te kōwhiringa rerekē (DNL) ki te tīpako i ngā kōwae i roto i te whakawhitinga ADC?

Mēnā ka pā te DNL ki te ±1 LSB, ka taea te whakaawe i ngā kōwae putanga e kore e kitea ētehi uara rorohiko. Ka whakaheke tēnei i te rerekētanga me te awhina i te stopi i te whakaaturanga tohu.

4. He aha te take e kiia ana ko te SINAD he tino whāinga whakaritenga atu i te SNR i roto i ngā pūnaha ao tūturu?

Ka uru te SINAD i te haruru me te parahanga harmonic, i te mea ko te SNR anake e e aro ana ki te haruru. Nā te mea ko ngā pūnaha ao tūturu e pā ana ki te pāhanga, ka rēhita te SINAD i te rerekē o te kounga tohu tūturu.

5. Me pehea e pā ana te ōvere te tango ki te whakapai i te mahi ADC i nga wāhi kōwhiri?

Ka noho te ōvere te tango hei whakawhānui i te haruru karanga i runga i te rārangi whānui, e tukuna ana te kōmaka matihiko ki te whakaheke i te haruru kei roto i te rārangi. Ka whakapai tēnei i te whakarōngia e whakatauranga ana me te mahi katoa o te tohu ki te haruru.

6. He aha te nohoanga i waenga i te hawhe pūmanawa me te whakatauranga ātirana i roto i ngā tohu input ADC?

Ko te hawhe pūmanawa ka taea te whakahaere i te tere kei te wātea te tango i te wā kaore e pāhemo te whakapae. Mēnā ka pā te tere ki te taha whakamahi te ngāwari o te ADC, ka puta te hopu i nga tawhiti i roto i nga herenga pūmanawa.