Crystal Oscillator Random Jitter, Deterministic Jitter, hte Phase Noise ni a lam hpe hkrak tup sang lang dan ai

Crystal Oscillator Random Jitter, Deterministic Jitter, hte Phase Noise ni a lam hpe hkrak tup sang lang dan ai

Crystal oscillator (XO/TCXO/OCXO) gaw, CPU, FPGA, hte -lawan dik ai interface ni a matu, aten masat masa galaw ya ai, electronic system ni a ahkying aten hpe jaw ya ai. Jitter gaw aten ladaw a hkrak ai lam hpe jep joi na matu core metric langai mi re - dai gaw aten ladaw signal a tengman ai jut hte kaja dik ai jut lapran na aten garan ai lam hpe tsun mayu ai, dai hpe aten ladaw a "timing error" ngu nna chye na la ma ai.

Crystal oscillator a jitter gaw langai kaw na pru wa ai n re; dai hpe madung lahkawng hku garan mai ai: Deterministic Jitter (DJ) hte Random Jitter (RJ) ngu ai. Engineering hta jitter hpe RMS Phase Jitter, RMS Period Jitter, hte Cycle-to-Cycle (CC) Jitter zawn re ai parameter ni hte shadawn shadang masat da ai. Ndai parameters ni gaw shada da matut mahkai nga ai raitim, jitter a dimension n bung ai hpe tsun dan ai.

1. Jitter a npawt nhpang amyu lahkawng: Deterministic Jitter (DJ) hte Random Jitter (RJ)

Ndai gaw crystal oscillator jitter hpe ahkyak dik htum garan ginhka ai lam rai nga ai. Dai lahkawng gaw npawt nhpang, arawn alai, kaja dik htum galaw lu ai lam ni hta tsep kawp shai hkat nga ai.

1.1 Dawdan ai Jitter (DJ)

Jitter gaw aten tup, hkan tam mai ai, shadawn sharam da ai, "shinggan na shingjawng ai lam a majaw byin pru wa ai gram lajang mai ai shut ai lam" ngu masat da ai.

Hpawt ni: N-gun jaw ai ripple, PCB crosstalk, lit n htap htuk ai, EMI, bungli galaw ai aten hta n kaja ai lam, kalang ta galai shai ai nsen

Laksan masa ni: Bai gram lajang mai ai, -Gaussian garan ginhka ai lam n re, shadawn sharam, yeng seng kau mai ai

Ga shadawn: Ahkying hpe ayan shadut nga ai; shamu shamawt ai lam hkring mat ai shaloi shut ai lam hkring mat ai

1.2 N myit mada ai sha n-gun n rawng ai (RJ)

Jitter gaw n tara ai, tau hkrau n tsun lu ai, tsep kawp ntsa tsang n nga ai, crystal oscillator a "shingra tara hku nna npawt nhpang nsen" hpe madi madun ai.

Npawt nhpang ni: Nbung nsen, flicker nsen, carrier galai shai ai lam, hte kaga hkum hkrang nsen ni

Laksan masa: Gaussian garan ginhka ai lam, tsep kawp n mai yeng seng kau ai, shayawm kau ai sha re .

Analogy: Ahkying aten kata na kaji kajaw shingra tara galai shai ai lam ni

1.3 Yawng hkra n-gun (TJ)

Tengman ai total jitter gaw dai lahkawng a ntsa kaw tawn da ai lam re.RMS manu ni hpe n-gun jat ai hku nna hpawng de da ai:TJRMS =RJRMS2 +DJRMS2

2. Engineering hte seng ai ga si ni hpe chye ra ai: Jitter a ahkyak ai masat masa 4

2.1 RMS daw n-gun n-gun (Random)

Random Jitter (RJ) sha lawm ai

Crystal oscillator a kata na nsen npu hpe madi madun ai

Circuit shingjawng ai lam n lawm ai sha, kristal a hkamja lam hpe madun dan ai

2.2 RMS daw n-gun (yawng)

RJ + DJ lawm ai

Tengman ai-system a bungli galaw ai lam hpe madun dan ai, grau nna lang ai phase jitter metric

2.3 RMS aten ladaw Jitter

RMS gaw, kaja dik ai shingjawng galu ai kaw nna, shingjawng ai aten ladaw langai a laklai ai lam

-ten galu na shingra tara ngang grin ai lam hpe madun dan ai

2.4 Hkrunlam - kaw nna-Hkrunlam hkawm ai (CC Jitter)

Htingbu htingbyen lahkawng a lapran na shai hkat ai lam hta galai shai ai lam

Kalang ta galai shai ai lam hpe madun dan ai; -lawan ai interface ni a matu grai ahkyak ai

3. Parameters hte DJ/RJ lapran na matut mahkai lam

Madung Sumtang:

Random Phase Jitter=san seng ai RJ sha

Kaga yawng=RJ + dawdan ai lam hta shang lawm ai lam (DJ)

4. Engineering hta jai lang ai lam: Lachyum shapraw nna manghkang hpe gara hku hparan na

→ RMS n-gun n-gun hpe jep yu u (Random)

Tengman ai-hpaji masa bungli galaw ai lam hpe jep joi yu u → RMS Phase Jitter (Yawng) hpe jep yu u

-lawan ai n-gun (PCIe/USB) → CC Jitter hpe madung tawn ai

Jitter grai law yang, shawng jep yu u: n-gun, ga, crosstalk, load (DJ a npawt nhpang yawng)

5. Jitter hte Phase Noise lapran na matut mahkai lam (Aten Domain ↔ Hkringmang Dap)

5.1 Ga si langai hta madung myit masa

Phase Nsen=chyahkring hkring-domain masat kumla

Hkrunlam Jitter=aten-domain masat kumla

Shanhte gaw gumhpraw langai a maga lahkawng rai nna, langai hte langai galai shai mai ai.

5.2 Madung laika shagun ai lam

RMS Random Phase Jitter↔ masat da ai bandwidth ntsa na nsen hpe shingdaw nna hkrak sha sawn la ai

Deterministic Jitter (DJ) ↔ gaw nsen n pru ai shara hta garan ginhka ai spurs ni hte bung ai

Random Jitter (RJ)↔ gaw, matut manoi nsen npu na nsen npu hte bung ai.

5.3 Hpaji hparat galai shai ai lam

Hpa majaw nga yang, n-gun n rawng ai nsen L(f) hpe n-gun n rawng ai shara langai mi ntsa e, RMS Phase Jitter hpe hkrak sha lu la ai.

Loi ai hku chye na na matu:

Phase nsen n-gun → a madang gaw jitter n-gun hpe dawdan ya ai

Lawu & n-gun n-gun → kaji ai jitter

Spikes (spurs) ni pru wa ai → Dawdan ai Jitter (DJ)

5.4 Hkrang shapraw ai lam

Phase nsen npu → Random Jitter (RJ) (n mai shaw kau ai)

Phase nsen pru wa ai → Dawdan ai Jitter (DJ) (manghkang hpe hparan mai ai)

Hkum tsup ai nsen nsam hpe hpawng de ai → yawng RMS Phase Jitter

6. Hpang jahtum Ultra-Kadun ai hku tsun dan ai

Jitter hta garan ginhka ai lam lahkawng nga ai:

DJ (Deterministic Jitter): shinggan kaw na shang lawm ai lam, yeng seng kau mai ai

RJ (Random Jitter): n-gun n rawng ai nsen, n mai yeng seng kau ai

Madung masat masa ni:

RMS Random Phase Jitter=san seng ai RJ

RMS yawng hkra n-gun n-gun=RJ + DJ

Aten ladaw Jitter=langai sha - shingjawng ai lam

CC Jitter=makau grup yin - shingjawng ai lam galai shai ai lam

Jitter ↔ Nsen:

Hkrun lam nsen (hkum hkrang n-gun) ↔ Hkrun lam Jitter (ten hkring)

Nsen npu → RJ

Spurs → DJ

Phase nsen hpe hpawng de ai → RMS Phase Jitter hpe hkrak shapraw ya ai