2007 EMC

EMC 2007. 9. 5

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 2

0. (Bypassing) (Decoupling) (power distribution system)

(Power plane) (Ground plane) (Components) (Internal power connections)

3

Decoupling PDN RF

Bypassing RF

Bulk DC

4

1. C RL

: LCR R > ZS : R < ZS :

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= = zero (IV)

X L = XC L = 1/ C = 1/ LC

= = zero (IV)6

= 1/ LC

C RL

1 R 1 0 = (R DC ESR.

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ESL ESL ESL

ESR: , DC , ESL:

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C : L : RS : PCB

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1 f = 2 LC

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2.1 De-cap: () .

I V / t I = current transient; t = switching time V = allowable power supply voltage change (ripple) C= De-cap: ,

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3. : ( : selfresonant frequency) , RF

SMT

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SMT (ESL = 1 nH)

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4. PCB

( ) : tr / tf > 10 ns TTL logic , de-cap , : 0.1 ~ 10 F

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(selfresonant frequency: SRF) SRF = de-cap SRF: (sharp resonance) ,

= PCB (unintentional radiator) EMI SRF de-cap PCB

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SRF []

PCB SRF: 200~400 MHz

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5. de-cap 6 dB

De-cap

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6. de-cap RF ESL ESR 2.5~10 nH

C = 8.85

R Ad

[pF]

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6.1 + , RF , , de-cap

ESL < 0.1 nH ESR < 0.5 ohms

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6.2 RF , (voltage gradients) RF RF Card cage RF

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RF

, PDN(Power Distribution Network) (image plane) () PCB RF

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6.3 De-cap , PCB , PCB PCB (solid plane) , SMT, ball grid arrays (BGA), flip chips PCB ,

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Rd LdCd

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EMI PCB IC de-cap Cd , PDS,