1 - General rules
1.1 PCB board pre- division digital, analog , DAA (data access arrangement, data access means ) the signal wiring region .
1.2 digital, analog components and the corresponding traces separated and placed in the respective wiring area.
1.3 high-speed digital signal traces as short as possible .
1.4 sensitive analog signal traces as short as possible .
1.5 rational allocation of power and ground.
1.6 DGND, AGND, field separately.
1.7 Critical Power and signal traces using a wide line.
1.8 digital circuit placed in parallel bus / serial nearby DTE interface , DAA circuit is placed near the telephone line interface .
2 Component placement
2.1 system circuit schematic :
a) dividing the digital , analog , DAA circuitry and its associated circuit ;
b) dividing each circuit in the digital , analog, mixed digital / analog components ;
c) Note that each IC chip power and signal positioning pin.
2.2 Preliminary division of digital, analog , DAA circuit in the wiring area ( generally the ratio of 2/1/1) PCB board , digital, analog components and their corresponding traces away and limited in their respective routing area .
Note: DAA circuit when a larger proportion will have more control / status signal traces across its routing area can be limited to make adjustments according to local rules, such as component spacing, high voltage suppression, the current restrictions.
2.3 Preliminary division is completed, from Jack Connector and start placing components.
