DESCRIPTION
The magnetic-latching TO-5 relay, originally conceived and developed by
Teledyne, has become one of the industry standards for low-level switching
from dry circuit to 1 ampere. Designed for high-density PC board mounting,
its small size and low coil power dissipation make the 420 and 422 relays
some of the most versatile ultraminiature relays available.
The following unique construction features and manufacturing techniques
provide excellent resistance to environmental extremes and overall high
reliability:
• All welded construction.
• Unique uni-frame design providing high magnetic efficiency and
mechanical rigidity.
• High force/mass ratios for resistance to shock and vibration.
• Advanced cleaning techniques provide maximum assurance of
internal cleanliness.
• Precious metal alloy contacts material with gold plating assures
excellent high current and dry circuit switching capabilities.
The Series 420D/422D and 420DD/422DD utilize discrete diodes for
coil suppression and polarity reversal protection.
By virtue of its inherently low intercontact capacitance and contact circuit
losses, these TO-5 relays have proven to be excellent ultraminiature RF
switches for frequency ranges well into the UHF spectrum. A typical RF
application for these TO-5 relays is in handheld radio receivers, wherein
the combined features of good RF performance, small size, very low
coil power dissipation and high reliability make it a preferred method of
transmit-receive switching
The Series 420/422 magnetic-latching relays are ideally suited for
applications where power dissipation must be minimized. The relays
can be operated with a short duration pulse. After the contacts have
transferred, no external holding power is required.
The magnetic latching feature of the Series 420/422 relays provide
a “memory” capability, since the relays will not reset upon removal of
coil power.