421 Series

TELEDYNE RELAYS
SERIES
421
ESTABLISHED RELIABILITY
TO-5 RELAYS
SPDT MAGNETIC LATCHING
SERIES
DESIGNATION
RELAY TYPE
421
SPDT basic relay
421D
SPDT relay with internal diode for coil transient suppression
421DD
SPDT relay with internal diodes for coil transient suppression and
polarity reversal protection
DESCRIPTION
The 421D and 421DD Series utilizes internal discrete silicon diodes for
coil suppression and polarity reversal protection.
The TO-5 relay, originally conceived and developed by Teledyne, has
become one of the industry standards for low level switching from dry
circuit to 0.5 ampere. Designed expressly for high density PC Board
mounting, its small size and low coil power dissipation make the TO-5
relay one of the most versatile ultraminiature relays available.
By virtue of its inherently low intercontact capacitance and contact circuit
losses, the TO-5 relay has shown itself to be an excellent ultraminiature
RF switch for frequency ranges well into the UHF spectrum. A typical
RF application for the TO-5 relay is in hand held radio transceivers,
wherein the combined features of good RF performance, small size,
low coil power dissipation and high reliability make it a preferred
method of Transmitter-Receive switching (see Figure 1).
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 contact material with gold plating assures
excellent high current and dry circuit switching capabilities.
The 421 Series 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 contacts have transferred, no external
holding power is required.
The magnetic latching feature of the 421 Series provides a “memory”
capability, since the relays will not reset upon removal of power.
PRINCIPLE OF OPERATION
Energizing Coil B produces a magnetic field opposing the
MAGNETIC CIRCUIT A
PERMANENT MAGNET
holding flux of the permanent magnet in Circuit B. As this MAGNETIC CIRCUIT B
SOFT IRON CORE A
net holding force decreases, the attractive force in the air
gap of Circuit A, which also results from the flux of the
COIL A
COIL B
permanent magnet, becomes great enough to break the
armature free of Core B, and snap it into a closed position SOFT IRON
SOFT IRON
CORE A
CORE B
against Core A. The armature then remains in this position
AIR GAP
upon removal of power from Coil B, but will snap back SOFT IRON
MOVING
into position B upon energizing Coil A. Since operation ARMATURE
CONTACT
depends upon cancellation of a magnetic field, it is
necessary to apply the correct polarity to the relay coils
as indicated on the relay schematic.
STATIONARY
CONTACT
When latching relays are installed in equipment, the
latch and reset coils should not be pulsed simultaneously.
Coils should not be pulsed with less than the nominal coil voltage and the pulse width should be
a minimum of three times the specified operate time of the relay. If these conditions are not
followed, it is possible for the relay to be in the magnetically neutral position.
41
ENVIRONMENTAL AND
PHYSICAL SPECIFICATIONS
Temperature
(Ambient)
-65°C to + 125°C
Vibration
30 g’s to 3000 Hz (Note 1)
Shock
100 g’s for 6 msec. (Note 1)
half-sine
Acceleration
50 g’s (Note 1)
Enclosure
All welded, hermetically sealed
Weight
0.089 oz (2.52 gms.) max.
SERIES 421
GENERAL ELECTRICAL SPECIFICATIONS
(-65°C to +125°C unless otherwise noted) (Notes 2 & 7)
Contact Arrangement
Rated Duty
Contact Resistance
Contact Load Rating (DC)
(See Fig. 2 for other DC
resistive voltage/current ratings)
1 Form C (SPDT)
Continuous
0.125 ohm max. before life; 0.225 ohm max. after life at 0.5A/28VDC, (measured 1/8” from header)
Resistive:
0.5 Amp/28VDC
Inductive:
200 mA/28VDC (320 mH)
Lamp:
100 mA/28VDC
Low Level: 10 to 50 µA/10 to 50 mV
Resistive:
250 mA/115VAC, 60 and 400Hz (Case not grounded)
100 mA/115VAC, 60 and 400Hz (Case grounded)
10,000,000 cycles (typical) at low level
00,100,000 cycles min. at all other loads specified above
2A/28VDC Resistive (100 cycles min.)
Contact factory
290 milliwatts typical at nominal rated voltage @ 25°C
1.5 msec max. at nominal rated coil voltage
1.5 msec max.
4.5 msec @ nominal voltage
0.4 pf typical
10,000 megohms min. between mutually isolated terminals
Atmospheric pressure: 500 VRMS/60 Hz
70,000 ft.: 125 VRMS/60Hz
Contact Load Ratings (AC)
Contact Life Ratings
Contact Overload Rating
Contact Carry Rating
Coil Operating Power
Operate Time
Contact Bounce
Minimum Operate Pulse
lntercontact Capacitance
Insulation Resistance
Dielectric Strength
Diode P.I.V.
421D, 421DD
Negative Coil Transient
421D, 421DD
100 VDC min.
1.0 VDC max.
DETAILED ELECTRICAL SPECIFICATIONS
(-65°C to +125°C unless otherwise noted) (Note 7)
BASE PART
NUMBERS
(See Note 9 for full P/N Example
Coil Voltage (VDC)
421-5
421D-5
421DD-5
➧
Nom.
Max.
421, 421D
421DD (Note 3)
Min.
Max.
421
421D
421DD
Coil Resistance
(Ohms ± 10% @ 25°C)
Coil Current (mADC @ 25°C)
421DD Series only
Set & Reset Voltage (VDC, Max.)
5.0
6.0
61
48
78.0
111.8
3.5
3.7
4.5
421-6
421D-6
421DD-6
421-9
421D-9
421DD-9
421-12
421D-12
421DD-12
421-18
421D-18
421DD-18
421-26
421D-26
421DD-26
6.0
8.0
120
97
45.8
63.0
4.5
4.5
5.5
9.0
12.0
280
280
25.7
34.9
6.8
6.8
7.8
12.0
16.0
500
500
19.6
26.7
9.0
9.0
10.0
18.0
24.0
1130
1130
13.4
18.8
13.5
13.5
14.5
26.5
32.0
2000
2000
11.2
15.2
18.0
18.0
19.0
PERFORMANCE CURVES
(NOTE 2)
TYPICAL RF PERFORMANCE
TYPICAL DC CONTACT RATING (RESISTIVE)
0
.1
300
INSER
TION
.3
LOSS
LOAD VOLTAGE (VDC)
.2
10
1.92
20
N LOSS
RETUR
30
1.22
SWR)
(V
1.07
40
50
60
1.02
TACTS
S CON
CROS
NA
OLATIO
1.01
VSWR
dB
.4
70
200
150
100
50
1.00
IS
250
1.00
.01
0.5
.1
.5
1.0
0
0.1
0.2
0.3
0.4
0.5
0.6
FREQUENCY (GHz)
LOAD CURRENT (AMPS DC)
FIGURE 1
FIGURE 2
42
0.7
0.8
0.9
1.0
SERIES 421
OUTLINE DIMENSIONS
TERMINAL LOCATIONS AND PIN NUMBERING (REF. ONLY)
(Viewed from Terminals)
SCHEMATIC DIAGRAMS
CASE DETAIL
.370
(9.40)
DIA. MAX.
.031 (.79)
± .003 (0.08)
COIL B
.335
(8.51)
DIA. MAX.
36° ±3° TYP.
9
.035 (.89)
± .010 (0.25)
1
.280 (7.11) MAX.
COIL A
2
8
7
.200 (5.08)
± .010 (.25) DIA.
421
6
4
WIRE LEAD: .75 (19.05) MIN.
PIN: .187 (4.75) ± .010 (.25)
(See Note 5)
COIL B
+.002 (.05)
.017 (.43) –.001 (.03) DIA.
DIMENSIONS ARE SHOWN IN INCHES (MILLIMETERS)
SPACER PAD
SPREADER PAD
Relays can be supplied with a spacer pad attached to the relay
header. The pad permits the relay to be spaced away from the
mounting surface facilitating solder joint inspection. To order add
M4 to the part number (e.g. ER421M4-26A).
Relays can be supplied with spreader pads which are attached
to the relays. Spreader pads can be supplied by adding M to the
part number (e.g. ER421M-26A).
.370 50 MAX
(9.40)
.150
(3.81)
COIL A
421D
COIL B
.100 (2.54)
.100 (2.54)
.300
(7.62)
COIL A
.305 MAX.
(7.75)
.200
(5.08)
(.41) .016
.18 .007
421DD
.398 MAX
(10.11)
NOTES:
NOTES:
SCHEMATICS ARE VIEWED FROM TERMINALS
1. Material: Diallyl Phthalate.
2. Increase contact resistance by 0.025 ohm.
3. Spreader pad conform to MIL-M-38527.
1. Material: Polyester film.
2. Increase contact resistance by 0.01 ohm.
COIL A LAST ENERGIZED
NOTES:
1.
2.
3.
4.
5.
Relay contacts will exhibit no chatter in excess of 10 µsec or transfer in excess of 1 µsec.
“Typical” characteristics are based on available data and are best estimates. No on-going verification tests are performed.
For reference only. Coil resistance not directly measurable at relays terminals due to internal series semiconductor. 421DD only.
Screened HI-REL versions available. Contact factory.
Unless otherwise specified, relays will be supplied as follows: Length will be standard 0.75” (19.05) minimum and will be either
gold plated or solder coated. Contact your local representative for ordering information.
6. The slash and characters appearing after the slash are not marked on the relay.
7. Unless otherwise specified, parameters are initial values.
8.
RELIABILITY LEVEL
FAILURE RATE %/10,000 CYCLES
A
1.5
B
0.75
9.
Teledyne Part Numbering System for Established Reliability Relays (See T2R® Program Introduction)
EXAMPLE:
ER 421 D Z M4 – 26
A / SQ
Established
Reliability Designator
Termination Variant
Q = Solder Coated Leads (Notes 5 and 6)
S = .187” Leads (Notes 5 and 6)
Relay Series
Reliability and Screening Level (Note 8)
D = Diode Suppression
DD = Diode Suppression and Polarity Protection
Coil Voltage
Mounting Variant
Ground Pin (See page 112)
M = Spreader Pad
M4 = Spacer Pad
©1996
TELEDYNE RELAYS
43
12525 Daphne Avenue
Hawthorne, California 90250