1) Single-sided PCB boards can be fabricated from just about any dielectric listed in IPC-4101 or IPC-4304 (flex) specifications.  The designer must define the objectives that they are trying to achieve--rigidity, low cost, impedance, assembly techniques, etc. before they specify what materials to use.

2) Again, depending on the device's objective, the thru holes can take many different options.  On a single-sided(?) PCB, there would not really be a need for "thru holes"---just drill the component hole thru the pad and assemble by soldering (or other options) the lead to the pad.  For double-sided PCB's and reliability, the standard plated thru process would be a first choice.

3)  The needed distance between thru hole pads is a function of the voltage, and can be as low as the spacing between adjacent lines.  Currently, many designs are being produced with >.004" spacing/line width.  The minimum spacing for voltages is listed in IPC-2221.

4)  The soldermask between adjacent conductors would generally be restricted to approximately a .002" dam. This is near the limits of "developability" of a photo-defined soldermask.  The side-wall development of unexposed resist would "meet" at the laminate surface, and the soldermask would fall off.

-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Chen Peiliang
Sent: Wednesday, June 02, 2004 9:59 PM
To: [log in to unmask]
Subject: Re: [IPC-600-6012] Question?

What base materials are used in Single Side PCBs, FR-4 or paper phenolic FR-1? 
What process for Thru Holes, electroless copper or carbon paste, silver paste?  

Regards,

Chen Peiliang
Shanghai Printronics Circuit
711 Yishan Road, Shanghai 200233
PR China
Tel: +86-21-6408 0192 x 507
Fax: +86-21-6436 3893 
e-mail:    [log in to unmask] 

----- Original Message ----- 
From: "Constantino J. Gonzalez" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, June 02, 2004 3:20 AM
Subject: [IPC-600-6012] Question?


Hello, can somebody tell me where can I find information on Single Side PCBs which consist of the following questions:

  1.. What is the distance between Thru Hole Pads?
  2.. What about Solder Mask Requirements between them?

Regards,
 
Constantino J. González
President/Consultant
IPC-A-610 Committee Chairman

ACME, INC.
A USA HISPANIC OWNED COMPANY
513 Cleveland Street, Suite # 300
Rapid City, SD 57701 USA
Cell # 605-381-5963
Fax # 605-341-4261
E-mail: [log in to unmask]