Series CCP-33S
Low PIM, Miniature DC–3 GHz
Latching SPDT Coaxial Switch
COAX SWITCHES
GLOSSARY
Actuator
including contact bounce. It consists of three parts: (1)
An actuator is the electromechanical mechanism that inductive delay in the coil, (2) transfer time of the physical
transfers the RF contacts from one position to another upon movement of the contacts, and (3) the bounce time of the
DC command.
RF contacts.
Arc Suppression Diode
TTL Switch Driver Option
A diode is connected in parallel with the coil. This diode As a special option, switch drivers can be provided for both
limits the “reverse EMF spike” generated when the coil de- failsafe and latching switches, which are compatible with
energizes to 0.7 volts. The diode cathode is connected to industry-standard low-power Schottky TTL circuits.
the positive side of the coil and the anode is connected to
the negative side.
Performance Parameters vs Frequency
Generally speaking, the RF performance of coaxial switches
is frequency dependent. With increasing frequency, VSWR
Date Code
All switches are marked with either a unique serial number and insertion loss increase while isolation decreases. All
or a date code. Date codes are in accordance with MIL- data sheets specify these three parameters as “worst case”
STD-1285 Paragraph 5.2.5 and consist of four digits. at the highest operating frequency. If the switch is to be
The first two digits define the year and the last two digits used over a narrow frequency band, better performance
define the week of the year (YYWW). Thus, 1032 identifies can be achieved.
switches that passed through final inspection during the
32nd week of 2010.
Actuator Current vs Temperature
The resistance of the actuator coil varies as a function of
temperature. There is an inverse relationship between the
Latching
A latching switch remains in the selected position whether operating temperature of the switch and the actuator drive
or not voltage is maintained. This can be accomplished current. For switches operating at 28 VDC, the approximate
with either a magnetic or mechanical latching mechanism.
actuator drive current at temperature, T, can be calculated
using the equation:
Indicator
I
A
I
=
Indicators tell the system which position the switch is in.
Other names for indicators are telemetry contacts or tellback
circuit. Indicators are usually a set of internally mounted DC
contacts linked to the actuator. They can be wired to digital
input lines, status lights, or interlocks. Unless otherwise
specified, the maximum indicator contact rating is 30 Vdc,
50 mA, or 1.5 Watts into a resistive load.
T
[1 + .00385 (T-20)]
Where:
I
I
=
=
Actuator current at temperature, T
T
Room temperature actuator current –
see data sheet
A
Isolation
T
=
Temperature of interest in °C
Isolation is the measure of the power level at the output
connector of an unconnected RF channel as referenced to Magnetic Sensitivity
the power at the input connector. It is specified in dB below An electro-mechanical switch can be sensitive to ferrous
the input power level.
materials and external magnetic fields. Neighboring ferrous
materials should be permitted no closer than 0.5 inches and
adjacent external magnetic fields should be limited to a flux
Self-Cutoff
The self-cutoff option disables the actuator current on density of less than 5 Gauss.
completion of actuation. Either a series contact (linked
to the actuator) or an IC driver circuit provides the current
cutoff. This option results in minimum power consumption
by the RF switch. Cutthroat is another name used in the
industry for this option. Pulse latching is a term used to
describe a switch without this feature.
SPDT Switch
A single-pole double-throw, bi-directional switch that can
be used as having one input and two outputs or two inputs
and one output.
Switching Time
Switching time is the total interval beginning with the arrival
of the leading edge of the command pulse at the switch DC
input and ending with the completion of the switch transfer,
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(800) 284-7007 • www.teledynecoax.com
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