신호 전송 품질을 보장하고 EMI 간섭을 줄이고 관련 임피던스 테스트 인증을 통과하려면 PCB 키 신호 임피던스 매칭 설계가 필요합니다. 이 설계 가이드는 공통 계산 매개변수, TV 제품 신호 특성, PCB 레이아웃 요구 사항, SI9000 소프트웨어 계산, PCB 공급업체 피드백 정보 등을 기반으로 최종적으로 권장 설계에 도달합니다. Suitable for most PCB suppliers’ process standards and PCB board designs with impedance control requirements.

하나. 이중 패널 임피던스 설계

① Ground design: line width, spacing 7/5/7mil ground wire width ≥20mil signal and ground wire distance 6mil, every 400mil ground hole; (2) Non-enveloping design: line width, spacing 10/5/10mil difference pair and the distance between the pair ≥20mil (special circumstances can not be less than 10mil) it is recommended that the whole group of differential signal line using enveloping shielding, differential signal and shielding ground distance ≥35mil (special circumstances can not be less than 20mil). 90옴 차동 임피던스 권장 설계

Line width, spacing 10/5/10mil Ground wire width ≥20mil Signal and ground wire distance of 6mil or 5mil, grounding hole every 400mil; ②Do not include the design:

Line width and spacing 16/5/16mil the distance between the differential signal pair ≥20mil it is recommended that ground enveloping be used for the whole group of differential signal cables. The distance between the differential signal and the shielded ground cable must be ≥35mil (or ≥20mil in special cases). Main points: give priority to the use of covered ground design, short line and complete plane can be used without covered ground design; Calculation parameters: Plate FR-4, plate thickness 1.6mm+/-10%, plate dielectric constant 4.4+/-0.2, copper thickness 1.0 oz (1.4mil) solder oil thickness 0.6±0.2mil, dielectric constant 3.5+/-0.3.

Impedance design of two and four layers

100 ohm differential impedance recommended design line width and spacing 5/7/5mil the distance between pairs ≥14mil(3W criterion) note: it is recommended that ground enveloping be used for the whole group of differential signal cables. The distance between the differential signal and the shielding ground cable should be at least 35mil (not less than 20mil in special cases). 90ohm differential impedance Recommended design line width and spacing 6/6/6mil Differential pair distance ≥12mil(3W criterion) Main points: In the case of long differential pair cable, it is recommended that the distance between the two sides of the USB differential line wrap the ground by 6mil to reduce EMI risk (wrap the ground and not wrap the ground, line width and line distance standard is consistent). 계산 매개변수: Fr-4, 판 두께 1.6mm+/-10%, 판 유전율 4.4+/-0.2, 구리 두께 1.0oz(1.4mil) 반경화 시트(PP) 2116(4.0-5.0mil), 유전율 4.3+/ -0.2 솔더 오일 두께 0.6±0.2mil, 유전율 3.5+/-0.3 적층 구조: 스크린 인쇄층 솔더층 구리층 반경화 필름 코팅 구리 기판 반경화 필름 구리층 솔더층 스크린 인쇄층

Three. Six layer board impedance design

The six-layer lamination structure is different for different occasions. This guide only recommends the design of the more common lamination (see FIG. 2), and the following recommended designs are based on the data obtained under the lamination in FIG. 2. The impedance design of the outer layer is the same as that of the four-layer board. Because the inner layer generally has more plane layers than the surface layer, the electromagnetic environment is different from the surface layer. The following are the suggestions for the impedance control of the third layer of wiring (laminated reference Figure 4). 90 ohm 차동 임피던스 권장 설계 라인 폭, 라인 거리 8/10/8mil 차이 쌍 거리 ≥20mil(3W 기준); 계산 매개변수: Fr-4, 판 두께 1.6mm+/-10%, 판 유전율 4.4+/-0.2, 구리 두께 1.0oz(1.4mil) 반경화 시트(PP) 2116(4.0-5.0mil), 유전율 4.3+/ -0.2 솔더 오일 두께 0.6±0.2mil, 유전율 3.5+/-0.3 적층 구조: 상부 스크린 차단층 구리층 반경화 구리 코팅 기판 반경화 구리 코팅 기판 반경화 구리 코팅층 하부 스크린 차단층

XNUMX개 또는 XNUMX개 이상의 레이어의 경우 관련 규칙에 따라 직접 설계하거나 관련 담당자와 상의하여 적층 구조 및 배선 방식을 결정하십시오.

5. If there are other impedance control requirements due to special circumstances, please calculate by yourself or consult relevant personnel to determine the design scheme

참고: ① 임피던스에 영향을 미치는 경우가 많습니다. PCB를 임피던스로 제어해야 하는 경우 임피던스 제어 요구 사항을 PCB 설계 데이터 또는 샘플 시트에 명확하게 표시해야 합니다. (2) 100옴 차동 임피던스는 주로 HDMI 및 LVDS 신호에 사용되며 HDMI는 관련 인증을 통과해야 합니다. ③ 90옴 차동 임피던스는 주로 USB 신호에 사용됩니다. (4) Single-terminal 50 ohm impedance is mainly used for part of DDR signal. Since most DDR particles adopt internal adjustment matching impedance design, the design is based on the Demo board provided by the solution company as a reference, and this design guide is not recommended. ⑤, single-end 75-ohm impedance is mainly used for analog video input and output. There is a 75-ohm resistance matching the ground resistance on the circuit design, so it is not necessary to carry out impedance matching design in PCB Layout, but it should be noted that the 75-ohm grounding resistance in the line should be placed close to the terminal pin. Commonly used PP.