Stripe-line pattern is etched on both sides of double-sided film. Since conductor thickness is only half that of single-sided film, problems in wrapping and etching are greatly reduced

Chen, T. T.

Zachry, C. L.

English

NASA Technical Reports Server

September 1975	 B75-10196 
NASA TECH BRIEF 
Langley Research Center
	 .4r 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
Low-Loss Stripe-Line Coil for Magnetic Bubble Memory Device 
An improved version of the stripe-line coil design 
presented in Langley Research Center Tech Brief 
B75-10195 (LAR-11705) has been developed. The 
total power dissipation of the coil depends on its 
overall resistance. It is desirable to have a stripe line 
with maximum conductor thickness and minimum 
insulation thickness for minimum coil size and power 
loss. Although the conductor film can be plated to 
several thousandths of an inch in thickness, problems 
still exist. 
a. A thick conductor film cannot be wrapped to a 
small radius as stress induced in the wrapping will 
cause cracking in the conductor, thereby increas-
ing electrical resistance and power dissipation. 
b. Stripe pattern etching in thick conductor film is 
more difficult because of the etch depth-to-width 
ratio, increasing etch loss in the stripe pattern and, 
therefore, increasing power loss of the coil.
The low-loss stripe-line coil design method is 
illustrated. Instead of doubling the conductor 
thickness on one side, an additional conductor film is 
placed on the back side of the insulator film to form a 
double-sided film. The stripe-line pattern is etched on 
both sides of the film, and since the conductor 
thickness is only half that of the equivalent 
single-sided film, the problems in wrapping and 
etching are greatly reduced. 
The stripe-line coil is wrapped in the same manner 
as when using single-sided film except that care has 
to be taken on aiming the stripe patterns between 
layers. Two electrical connections between layers (B 
and C on the illustration) assure that conductor layers 
in close contact are all of the same electrical potential. 
With this arrangement no electrical insulation is 
required between layers, reducing the insulator film to 
one-half that required for single-sided conductor coil. 
Conductor 
A	 Insulator 
(a) Stripe-Line Coil Structure 
A
B'
(b) Equivalent Conductor Path 
Stripe-Line Coil Structure With Double-Sided
Conductor Strip
(continued overleaf) 
This document was prepared under the sponsorship of the National	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration. Neither the United States	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States 	 will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19750000196 2020-03-19T20:27:46+00:00Z
Note: 
Requests for further information may be directed 
to:
Technology Utilization Officer 
Langley Research Center 
Mail Stop 139-A 
Hampton, Virginia 23665 
Reference: B75-10196
Patent status: 
Title to this invention has been waived under the 
provisions of the National Aeronautics and Space Act 
[42 U.S.C. 2457(0], to the Rockwell International 
Corporation, Anaheim, California 92803. 
Source: Thomas T. Chen and

Clyde L. Zachry of

Rockwell International Corp.

(LAR-11707) 
Categories: 01 (Electronics - Components 
and Circuitry) 
B75-10196	 02 (Electronics Systems)


Low-loss stripe-line coil for magnetic bubble memory

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server