Hpa majaw Network jak ni gaw 25MHz hte shi a law law hpe Frequency hku lang ai kun?

Hpa majaw Network jak ni gaw 25MHz hte shi a law law hpe Frequency hku lang ai kun?

Network card, switch, router, Ethernet jak ni zawn re ai network jak ni hta, crystal oscillator frequency hpe lata ai lam gaw, jak a madung bungli ni, chip ra ai lam ni, matut mahkai ai lam a madang ni hpe yu nna dawdan ai. 25MHz frequency hte shi a law law lang lang ai crystal oscillator ni hpe jai lang ai lam gaw madung hku nna ndai frequency system gaw Ethernet madang, matut mahkai tara ni, chip architecture ni hte grai ni htep ai majaw, asan sha galaw lu ai, manu jahpu hpe shayawm lu ai, bungli galaw ai lam hpe grau kaja hkra galaw lu ai. Lawu na hta hkrak tup sang lang dan da ai.

I. Hpa majaw 25MHz hpe Base Frequency hku lata ai kun?

25MHz gaw tinang ra sharawng ai hku lata la ai manu n re. Network matut mahkai lam hta core frequency law law hte integer multiple matut mahkai lam nga ai majaw, frequency hpe law htam ai (sh) garan ai lam hpe loi ai hku galaw ai majaw, grai lang ai.

1.1 Ethernet masat da ai frequency ra kadawn ai lam ni hpe hkan sa ai

Lawan ai Ethernet (100BASE-TX): 25MHz ahkying hpe data shapoi ai n-gun hku lang ai.

Gigabit Ethernet (1000BASE-T): 125MHz ahkying hpe lang ai, dai gaw 25MHz × 5 re.

10GbE (10 Gigabit Ethernet) hte dai hta jan ai: Madung aten ladaw a nsen gaw grau law ai raitim (ga shadawn, 156.25MHz), PLL hku nna 25MHz n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun hpe PLL hku nna law htam ai hku nna law malawng lu la mai ai.

Ndai gaw 25MHz gaw, npawt nhpang ahkying frequency hku nna, PHY/MAC a bungli galaw ai frequency ni hpe, Ethernet lawan ai lam a matu, hkrak (sh) n hkrak ai hku madi shadaw ya lu ai hpe madun nga ai.

II. Hpaji masa hku galaw sa wa na matu shim lum ai

2.1 PLL hku nna loi ai hku Frequency law htam wa ai

Network chip ni (PHY, MAC, hte switch chip zawn re ai ni) gaw, ra ai bungli galaw ai aten ladaw hpe shapraw na matu, PLL (Phase Locked Loop) circuit ni hpe kata kaw lang chye ma ai. 25MHz gaw, n-gun kaba ai -lawan ai nsen ni hpe hkrak hkra shapraw lu ai, n-gun n-gun hpe shapraw lu ai, n-gun n-gun hpe n-gun n-gun hte shapraw lu ai:

MHz × 2=50MHz

MHz × 4=100MHz

MHz × 5=125MHz

25MHz × 6.25=156.25MHz (10GbE a matu)

25MHz gaw n law ai integer law law hpe {-hti na matu loi ai base frequency re majaw, PLL design hpe asan sha galaw ya ai, grau lawan ai hku lock galaw ya lu ai, grau ngang grin ai pru wa ai lam hpe mung lu la shangun ai.

2.2 Madung Chip Ra ai lam ni hte htap htuk ai

Network jak chip galaw ai ni law malawng (Broadcom, Realtek, Marvell, Intel zawn re ai ni) gaw shanhte a PHY (sh) MAC chip ni a shang ai aten ra ai lam ni hta 25MHz crystal oscillator shang ai hpe asan sha madi shadaw ya ai, shing nrai 25MHz shang ai aten a matu bungli galaw ai ladat ni hpe jaw ya ai.

III. EMC, Circuit hkrang shapraw ai lam, manu jahpu ni hta akyu nga ai

3.1 EMI hpe grau kaja hkra hkang lu ai hte Signal hpe grau tsaw ai hku hkang lu ai

25MHz gaw, n-gun grau ja ai (ga shadawn, 50MHz, 100MHz, 125MHz, 150MHz, hte 200MHz) nga ai crystal oscillator ni hte shingdaw yu yang, 25MHz gaw, n-gun n-gun n-gun (EMI) hte seng nna, ahkyak ai akyu ni hpe jaw ya nga ai:

Npu na npawt nhpang frequency gaw, harmonic n-gun n law ai hpe shabyin ya ai;

PCB routing gaw EMI design masat masa ni hpe hkan sa na matu loi ai;

Enclosures hte power integrity a matu ra kadawn ai lam ni hpe shayawm ya ai, system hpe hpawng de na matu loi ai.

3.2 Kungkyang ai, ngang grin ai, manu dan ai-Kaja ai Crystal Oscillator ni

25MHz crystal oscillators ni gaw, electronic hpaga lam hta grau nna jai lang ai frequency ni hta lawm nna, lawu na akyu ni nga ai:

Off-the-shelf arung arai ni law law hte amyu myu nga ai;

Hpaga lam manu n law ai hte mari la mai ai manu n law ai;

Aten kadun ai hte ngang grin ai quality nga ai kungkyang ai supply chain.

Ndai gaw, kaba ai-hpe galaw ai network device galaw ai ni a matu grai myit lawm hpa rai nga ai.

IV. Tatut hkrang shapraw ai hta jai lang ai ga shadawn

Gigabit Ethernet hpe ga shadawn hku nna la ga:

Madung hkang ai chip gaw 125MHz ngu ai input bungli galaw ai frequency ra ai;

Design hta 25MHz crystal oscillator hpe lang mai ai, dai chip hta bang da ai-PLL hku nna frequency hpe 125MHz de jat mai ai;

Dai laman, 25MHz ahkying hpe kaga module ni (PHY, MAC, shing nrai ahkying hpe shingdaw ai module ni zawn re ai) de ahkying hpun hku nna garan mai ai;

Ndai hku galaw ai gaw, langai sha re ai ahkying source hpe lu la ai, ahkying architecture hpe asan sha galaw ya ai, system a yak hkak ai lam hte manu jahpu hpe shayawm ya lu ai.

Gadun dawk

Network jak ni hta 25MHz hte shi a law law hpe crystal oscillator frequency hku jai lang ai lam a lachyum ni hpe lawu na hte maren shingdaw mai ai:

Hangjing Crystal Oscillators hpe gaw, n-gun n rawng ai jak ni (network card, switch, router, ethernet) ni hta grai lang ma ai. Industrial-grade arung arai ni hta n-ga, anhte gaw n-gun ja ai n-gun ja ai n-gun ja ai n-gun (-55~+125℃) hpe mung jaw ya nna, n-gun ja ai jak hpe jai lang ai lam hte htuk manu ai hparan ladat ni hpe mung jaw ya lu ai. Nang hta ra kadawn ai lam ni nga yang, Hangjing a dut mari (sh) hpaji ninghkring ni hpe matut mahkai mai ai.