Electrical
Controlling Impedance and Electrical Noise
Predictable electrical characteristics make flex-circuits
an ideal choice for high-speed signal transmission.
Uniform spacing between conductors and grounds,
continuous shield layers, and repeatable geometries are
features that help to control impedance and reduce
crosstalk. And with flex-circuits, you can eliminate
connectors and other transitions that contribute to
signal attenuation.
Flex-circuit design options to control impedance and
EMI include:
·
Microstrip a single ground plane beneath the signal
lines.
·
Stripline dual ground layers above and below the
signal lines.
·
Alternating ground and signal lines in the same plane.
·
Rigid-flex/stiffened flex-circuits with uninterrupted
ground layers
·
Silver epoxy coating. Silver epoxy is applied to the
outside of circuits and electrically connected to other
layers via access holes in the cover coat. Silver epoxy
shielding can be less costly and is more flexible than
copper.
Minco can provide tight tolerance on line width,
spacing, and distance to ground layers in order to meet
your required impedance value. Actual impedance will
also depend on the circuit's shape after installation.
Contact Minco for advice on designing circuits to
specific electric characteristics.
Flex-CoilsTM
Flex-Coils are flex-circuits containing integral wire coils
for use as antennas or inductors. There are three basic
types of Flex-Coils:
·
Simple, flat coils with wire leads
·
Coils laminated inside flex-circuits
·
`Rim' coils that are built up in the Z-axis.
Flex-Coils have the same advantages that a flex-circuit
does. Wiring errors are reduced because the coil is
oriented in the same spot every time, which provides
repeatable signals. Flex-Coils are rugged and easy to
assemble, and their design usually guarantees a
reduced package size. A Flex-Coil can terminate in any
manner that a flex-circuit can, or to a wire lead. Heavy
wire leads are available.
See Bulletin FC-1, Flex-Coils, for more information on
Flex-Coil capabilities, design considerations, and the
information required for a quote or build.
Minco Flex-CoilTM
Signal
Ground
Ground
Signal
Ground
Signal
Ground
Coil-to-Circuit
Termination
Wire Coil
Etched Conductor
Flex-Coil
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Tel: (763) 571-3121 K Fax: (763) 571-0927 K www.minco.com
Application Aid #24