1-593
HERMETIC/HI-REL
OPTOCOUPLERS
5965-1142E
H
90 V/1.0 Ω, Hermetically Sealed,
Power MOSFET Optocoupler
Technical Data
Features
• Dual Marked with Device
Part Number and DESC
Standard Military Drawing
• ac/dc Signal & Power
Switching
• Compact Solid-State
Bidirectional Switch
• Manufactured and Tested on
a MIL-PRF-38534 Certified
Line
• QML-38534
• MIL-PRF-38534 Class H
• Space Level Processing
Available
• Hermetically Sealed 8-Pin
Dual In-Line Package
• Small Size and Weight
• Performance Guaranteed
over -55°C to +125°C
• Connection A
0.8 A, 1.0 Ω
• Connection B
1.6 A, 0.25 Ω
• 1500 Vdc Withstand Test
Voltage
• High Transient Immunity
• 5 Amp Output Surge Current
Applications
• Military and Space
• High Reliability Systems
• Standard 28 Vdc and 48 Vdc
Load Driver
• Standard 24 Vac Load Driver
• Aircraft Controls
• ac/dc Electromechanical and
Solid State Relay
Replacement
• I/O Modules
• Harsh Industrial
Environments
eight-pin, hermetic, dual-in-line,
ceramic packages. The devices
operate exactly like a solid-state
relay. The products are capable of
operation and storage over the
full military temperature range
and can be purchased as a
standard product (HSSR-7110),
with full MIL-PRF-38534 Class H
testing (HSSR-7111), or from the
DESC Standard Military Drawing
(SMD) 5962-93140.
These devices may be purchased
with a variety of lead bend and
plating options. See Selection
Guide Table for details. Standard
Military Drawing (SMD) parts are
available for each lead style.
Description
The HSSR-7110, HSSR-7111 and
SMD 5962-9314001 are single
channel power MOSFET
optocouplers, constructed in
Functional Diagrams
CONNECTION A
AC/DC CONNECTION
2
3
4
1
6
7
5
8
V
F
NC
NC
O
V
I
F
+
_
O
I
+
_
•
•
CONNECTION B
DC CONNECTION
2
3
4
1
6
7
5
8
V
F
NC
NC
O
V
I
F
+
_
O
I
+
_
•
•
TRUTH TABLE
INPUT OUTPUT
H CLOSED
L OPEN
CAUTION: It is advised that normal static precautions be taken in handling and assembly of this component
to prevent damage and/or degradation which may be induced by ESD.
HSSR-711X*
5962-9314001
*See matrix for available extensions
1-594
All devices are manufactured and
tested on a MIL-PRF-38534 certi-
fied line and are included in the
DESC Qualified Manufacturers
List, QML-38534 for Hybrid
Microcircuits. Each device
contains an AlGaAs light emitting
diode optically coupled to a
photovoltaic diode stack which
drives two discrete power
MOSFETs. The device operates
as a solid-state replacement for
single-pole, normally open,
(1 Form A) relays used for
general purpose switching of
signals and loads in high
reliability applications.
The devices feature logic level
input control and very low output
on-resistance, making them
suitable for both ac and dc loads.
Connection A, as shown in the
Functional Diagram, allows the
device to switch either ac or dc
loads. Connection B, with the
polarity and pin configuration as
shown, allows the device to
switch dc loads only. The
advantage of Connection B is that
the on-resistance is significantly
reduced, and the output current
capability increases by a factor of
two.
The devices are convenient
replacements for mechanical and
solid state relays where high
component reliability with
standard footprint lead configu-
ration is desirable. Devices may
be purchased with a variety of
lead bend and plating options.
See Selection Guide table for
details. Standard Military
Drawing (SMD) parts are
available for each package and
lead style.
The HSSR-7110, HSSR-7111, and
SMD 5962-93140 are designed to
switch loads on 28 Vdc power
systems. They meet 80 V surge
and ±600 V spike requirements.
3.81 (0.150)
MIN.
4.32 (0.170)
MAX.
9.40 (0.370)
9.91 (0.390)
0.51 (0.020)
MAX.
2.29 (0.090)
2.79 (0.110)
0.51 (0.020)
MIN.
0.76 (0.030)
1.27 (0.050)
8.13 (0.320)
MAX.
7.36 (0.290)
7.87 (0.310)
0.20 (0.008)
0.33 (0.013)
7.16 (0.282)
7.57 (0.298)
NOTE: DIMENSIONS IN MILLIMETERS (INCHES).
Outline Drawing
8-pin DIP Through Hole
Selection Guide–Package Styles and Lead
Configuration Options
HP Part # and Options
Commercial HSSR-7110
MIL-PRF-38534 Class H HSSR-7111
Standard Lead Finish Gold
Solder Dipped Option #200
Butt Joint/Gold Plate Option #100
Gull Wing/Soldered Option #300
Crew Cut/Gold Plate Option #600
SMD Part #
Prescript for all below 5962-
Either Gold or Soldered 9314001HPX
Gold Plate 9314001HPC
Solder Dipped 9314001HPA
Butt Joint/Gold Plate 9314001HYC
Butt Joint/Soldered 9314001HYA
Gull Wing/Soldered 9314001HXA
Crew Cut/Gold Plate 9314001HZC
Crew Cut/Soldered 9314001HZA
1-595
HERMETIC/HI-REL
OPTOCOUPLERS
Recommended Operating Conditions
Parameter Symbol Min. Max. Units
Input Current (on) IF(ON) 520mA
Input Voltage (off) VF(OFF) 0 0.6 V
Operating Temperature TA-55 +125 °C
Device Marking
Absolute Maximum Ratings
Storage Temperature Range ........................................ -65°C to +150°C
Operating Ambient Temperature – TA.......................... -55°C to +125°C
Junction Temperature – TJ......................................................... +150°C
Operating Case Temperature – TC......................................... +145°C[1]
Lead Solder Temperature ............................................... 260°C for 10 s
(1.6 mm below seating plane)
Average Input Current – IF........................................................... 20 mA
Peak Repetitive Input Current – IFPK ............................................ 40 mA
(Pulse Width < 100 ms; duty cycle < 50%)
Peak Surge Input Current – IFPK surge ....................................... 100 mA
(Pulse Width < 0.2 ms; duty cycle < 0.1%)
Reverse Input Voltage – VR............................................................... 5 V
Average Output Current – Figure 2
Connection A – IO....................................................................... 0.8 A
Connection B – IO...................................................................... 1.6 A
Single Shot Output Current – Figure 3
Connection A – IOPK surge (Pulse width < 10 ms)...................... 5.0 A
Connection B – IOPK surge (Pulse width < 10 ms) ................... 10.0 A
Output Voltage
Connection A – VO...................................................... -90 V to +90 V
Connection B – VO..........................................................0 V to +90 V
Average Output Power Dissipation – Figure 4 .......................800 mW[2]
Thermal Resistance
Maximum Output MOSFET Junction to Case – θJC = 15°C/W
ESD Classification
(MIL-STD-883, Method 3015) .......................................... (∆∆), Class 2
COMPLIANCE INDICATOR,*
DATE CODE, SUFFIX (IF NEEDED)
HP QYYWWZ
XXXXXX
XXXXXXX
XXX USA
50434 COUNTRY OF MFR.
HP FSCN*
HP LOGO
DESC SMD*
PIN ONE/
ESD IDENT
HP P/N
DESC SMD*
* QUALIFIED PARTS ONLY
1-596
0.51 (0.020)
MIN.
5.57 (0.180)
MAX.
0.51 (0.020)
MAX.
2.29 (0.090)
2.79 (0.110)
1.40 (0.055)
1.65 (0.065) 9.65 (0.380)
9.91 (0.390)
5° MAX.
5.57 (0.180)
MAX.
0.20 (0.008)
0.33 (0.013)
Option Description
Hermetic Optocoupler Options
100 Surface mountable hermetic optocoupler with leads trimmed for butt joint assembly. This option
is available on commercial and hi-rel product.
200 Lead finish is solder dipped rather than gold plated. This option is available on commercial and
hi-rel product. DESC Drawing part numbers contain provisions for lead finish.
300 Surface mountable hermetic optocoupler with leads cut and bent for gull wing assembly. This
option is available on commercial and hi-rel product. This option has solder dipped leads.
600 Surface mountable hermetic optocoupler with leads trimmed for butt joint assembly. This option
is available on commercial and hi-rel product.
Note: Dimensions in millimeters (inches).
1.14 (0.045)
1.40 (0.055)
4.32 (0.170)
MAX.
0.51 (0.020)
MAX.
2.29 (0.090)
2.79 (0.110)
0.51 (0.020)
MIN.
7.36 (0.290)
7.87 (0.310)
0.20 (0.008)
0.33 (0.013)
NOTE DIMENSIONS IN MILLIMETERS (INCHES)
3.81 (0.150)
MAX.
1.02 (0.040)
TYP.
2.29 (0.090)
2.79 (0.110)
0.51 (0.020)
MIN. 7.36 (0.290)
7.87 (0.310)
0.20 (0.008)
0.33 (0.013)
1-597
HERMETIC/HI-REL
OPTOCOUPLERS
Electrical Specifications
TA =-55°C to +125°C, unless otherwise specified. See note 9.
Group
A, Sub-
Parameter Sym. group Test Conditions Min. Typ.* Max. Units Fig. Notes
Output Withstand |V
O(OFF)
| 1, 2, 3 V
F = 0.6 V, IO = 10 µA 90 110 V 5
Voltage
Output Connection R(ON) 1, 2, 3 IF = 10 mA, IO = 800 mA, 0.40 1.0 Ω6,7 3
On- A (pulse duration ≤30 ms)
Resistance
Connection IF = 10 mA, IO = 1.6 A, 0.12 0.25
B (pulse duration ≤30 ms)
Output Leakage IO(OFF) 1, 2, 3 V
F = 0.6 V, VO = 90 V, 10-4 10 µA8
Current
Input Forward V
F1, 2, 3 IF = 10 mA 1.0 1.24 1.7 V 9
Voltage
Input Reverse V
R1, 2, 3 IR = 100 µA 5.0 V
Breakdown Voltage
Input-Output II-O 1 RH ≤ 45%, t = 5 s, 1.0 µA 4, 5
Insulation VI-O = 1500 Vdc,
TA = 25°C
Turn On Time tON 9, 10, 11 IF = 10 mA, VDD = 28 V, 1.25 6.0 ms 1,10,
IO = 800 mA 11,12,
13
Turn Off Time tOFF 9,10,11 IF = 10 mA, 0.02 0.25 ms 1,10,
VDD = 28 V, IO = 800 mA 14,15
Output Transient dVo 9 VPEAK = 50 V, 1000 V/µs17
Rejection dt CM = 1000 pF,
CL = 15 pF, RM ≥ 1 MΩ
Input-Output dVio 9 V
DD = 5 V, 500 V/µs18
Transient Rejection dt VI–O(PEAK) = 50 V,
RL = 20 kΩ, CL = 15 pF
*All typical values are at TA = 25°C, IF(ON) = 10 mA, VF(OFF) = 0.6 V unless otherwise specified.
1-598
CAUTION: Maximum Switching Frequency – Care should be taken during repetitive switching of
loads so as not to exceed the maximum output current, maximum output power dissipation,
maximum case temperature, and maximum junction temperature.
Figure 1. Recommended Input Circuit.
R1 = REQUIRED CURRENT LIMITING RESISTOR
FOR I = 10 mA.
R2 = PULL-UP RESISTOR FOR V < 600 mV;
IF (V - V ) < 600 mV, OMIT R2.
R3, C = OPTIONAL PEAKING CIRCUIT.
CC
F (0N) F (OFF)
OH
TYPICAL VALUES
R3
(Ω)I
(mA) HSSR-7110
t (ms)
–
330
100
33
10 (NO PK)
20
40
100
2.0
1.0
0.48
0.22
F (PK) ON
CC
* USE SECOND GATE IF I > 50 mA
REMINDER: TIE ALL UNUSED INPUTS TO GROUND OR V
F (PK)
IN
1/4 54ACTOO*
1/4 54ACTOO
V (+5V)
CC
R2
1200Ω
R1
330Ω
R3
C
15 µF
HSSR-7110
2
3
4
1
6
7
5
8
_
I
F
V
F
+
Typical Characteristics
All typical values are at TA = 25°C, IF(ON) = 10 mA, VF(OFF) = 0.6 V unless otherwise specified.
Parameter Symbol Test Conditions Typ. Units Fig. Notes
Output Off-Capacitance CO(OFF) VO = 28 V, f = 1 MHz 145 pF 16
Output Offset Voltage |VOS|I
F
= 10 mA, IO = 0 mA 2 µV197
Input Diode Temperature ∆VF/∆TAIF = 10 mA -1.4 mV/C
Coefficient
Input Capacitance CIN VF = 0 V, f = 1 MHz 20 pF 8
Input-Output Capacitance CI-O VI-O = 0 V, f = 1 MHz 1.5 pF 4
Input-Output Resistance RI-O VI-O = 500 V, t = 60 s 1013 Ω4
Turn On Time tON IFPK = 100 mA, 0.22 ms 1 6
With Peaking IFSS = 10 mA
VDD = 28 V, IO = 800 mA
Notes:
1. Maximum junction to case thermal resistance for the device is 15°C/W, where case temperature, TC, is measured at the center of the
package bottom.
2. For rating, see Figure 4. The output power PO rating curve is obtained when the part is handling the maximum average output current
IO as shown in Figure 2.
3. During the pulsed RON measurement (IO duration <30 ms), ambient (TA) and case temperature (TC) are equal.
4. Device considered a two terminal device: pins 1 through 4 shorted together and pins 5 through 8 shorted together.
5. This is a momentary withstand test, not an operating condition.
6. For a faster turn-on time, the optional peaking circuit shown in Figure 1 may be implemented.
7. VOS is a function of IF, and is defined between pins 5 and 8, with pin 5 as the reference. VOS must be measured in a stable ambient
(free of temperature gradients).
8. Zero-bias capacitance measured between the LED anode and cathode.
9. Standard parts receive 100% testing at 25°C (Subgroups 1 and 9). SMD and class H parts receive 100% testing at 25°C, 125°C and
-55°C (Subgroups 1 and 9, 2 and 10, 3 and 11 respectively).
1-599
HERMETIC/HI-REL
OPTOCOUPLERS
V = 0.6V
I = 10 µA
F
O
-55
T – AMBIENT TEMPERATURE – °C
A
12595655-25
0.92 35
NORMALIZED TYPICAL OUTPUT
WITHSTAND VOLTAGE
0.94
0.96
0.98
1.00
1.02
1.04
1.06
1.08
1.10
Figure 6. Normalized Typical Output
Resistance vs. Temperature.
Figure 5. Normalized Typical Output
Withstand Voltage vs. Temperature. Figure 7. Typical On State Output I-V
Characteristics.
0-55
T – AMBIENT TEMPERATURE – °C
A
1.0
0.4
15512595655-25
0.6
0.8
0.2
35
I – OUTPUT CURRENT – A
O
CONNECTION – A
I ≥ 10 mA
θ = 40° C/W
θ = 80° C/W
CA
CA
F
I SURGE – OUTPUT CURRENT – A
OPK
31000
PULSE DURATION – ms
8
5
400200
6
7
4
9
10
11
12
600 800
I ≥ 10mA
F
CONNECTION–A
CONNECTION–B
10
0-55
T – AMBIENT TEMPERATURE – °C
A
1.0
0.4
15512595655-25
0.6
0.8
0.2
35
CONNECTION – A
I ≥ 10 mA
θ = 40° C/W
θ = 80° C/W
CA
CA
F
P – OUTPUT POWER
DISSIPATION – W
O
Figure 2. Maximum Average Output
Current Rating vs. Ambient
Temperature.
Figure 3. Single Shot (non-repetitive)
Output Current vs. Pulse Duration. Figure 4. Output Power Rating vs.
Ambient Temperature.
NORMALIZED TYPICAL
OUTPUT RESISTANCE
-55
T – AMBIENT TEMPERATURE – °C
A
12595655-25
0.6 35
0.8
1.0
1.2
1.4
1.6
1.8 CONNECTION – A
I 10 mA
I = 800 mA
F
O
(PULSE DURATION ≤ 30 ms)
>
V – OUTPUT VOLTAGE – V
O
I – OUTPUT CURRENT – A
O
-0.6 0.60.40.2-0.2-0.4
-0.4
0
-0.2
0
0.2
0.4
0.6
0.8
-0.8
-0.6
T = 25°C
A
T = 125°C
A
T = -55°C
A
CONNECTION – A
I 10 mA
I (PULSE DURATION
≤ 30 ms)
F
O
>
Figure 9. Typical Input Forward
Current vs. Input Forward Voltage.
Figure 8. Typical Output Leakage
Current vs. Temperature.
-11
10
-7
10
-8
10
-9
10
-10
10
I – OUTPUT
LEAKAGE CURRENT – A
O(OFF)
T – TEMPERATURE – °C
A
125956520 35
CONNECTION A
V = 0.6V
V = 90V
F
O
T = 25°C
A
T = 125°C
A
T = -55°C
A
V – INPUT FORWARD VOLTAGE – V
F
0.6 1.61.41.20.80.4 1.0
-1
10
-2
10
-4
10
-3
10
-5
10
-6
10
I – INPUT FORWARD
CURRENT – A
F
1-600
Figure 10. Switching Test Circuit for tON, tOFF.
Figure 11. Typical Turn On Time vs.
Temperature. Figure 12. Typical Turn On Time vs.
Input Current. Figure 13. Typical Turn On Time vs.
Voltage.
50%
10%
50%
90%
ON
tOFF
t
P.W. = 15 ms
VO
F
I
F
I
HSSR-7110
2
3
4
1
6
7
5
8
PULSE GEN.
Z = 50Ω
t = t = 5ns
O
fr L
R
GND
(C INCLUDES PROBE AND
FIXTURE CAPACITANCE)
L
DD
V
L
C = 25 pF
F
I
MONITOR
R (MONITOR)
200Ω
GND
MONITOR NODE
VO
+
_F
V
Figure 14. Typical Turn Off Time vs.
Temperature. Figure 15. Typical Turn Off Time vs.
Input Current. Figure 16. Typical Output Off
Capacitance vs. Output Voltage.
V – OUTPUT VOLTAGE – V
O(OFF)
515100
120
320
280
240
200
160
360
400
302520
440
C – OUTPUT OFF
CAPACITANCE – pF
O(OFF)
CONNECTION A
f = 1MHz
T = 25°C
A
5
40
35
30
25
20
15
10
45
T – TURN OFF TIME – µs
OFF
I – INPUT CURRENT – mA
F
10 15 205
CONNECTION A
V = 28V
I = 800mA
T = 25°C
A
DD
O
T – TEMPERATURE – °C
A
13.2
14.6
14.4
14.2
14.0
13.8
13.6
13.4
14.8
15.0
T – TURN OFF TIME – µs
OFF
-55 12595655-25 35
CONNECTION A
I = 10mA
V = 28V
I = 800mA
F
DD
O
V – VOLTAGE – V
DD
10 30200
0
1.0
0.8
0.6
0.4
0.2
1.2
1.4
T – TURN ON TIME – ms
ON
908070605040
2.0
1.8
1.6 T = 25°C
A
CONNECTION - A
I = 10 mA
I = 800 mA
F
O
I – INPUT CURRENT – mA
F
10 15 205
0.2
2.2
1.8
1.4
1.0
0.6
2.6
3.0
T – TURN ON TIME – ms
ON
CONNECTION A
V = 28V
I = 800mA
T = 25°C
A
DD
O
T – TEMPERATURE – °C
A
0.8
2.2
2.0
1.8
1.6
1.4
1.2
1.0
2.4
2.6
T – TURN ON TIME – ms
ON
-55 12595655-25 35
CONNECTION A
I = 10mA
V = 28V
I = 800mA
F
DD
O
1-601
HERMETIC/HI-REL
OPTOCOUPLERS
Figure 17. Output Transient Rejection Test Circuit.
PEAK
V
tfr
t
90%
10%
90%
10%
V (MAX) ≤ 5V
M
OVERSHOOT ON V IS TO BE ≤ 10%.
PEAK
t
d
dVoOR
=tf
(0.8) V(PEAK)
r
t
(0.8) V(PEAK)
HSSR-7110
2
3
4
1MONITOR
NODE
+
_
_
PULSE
GENERATOR
PEAK
V
+
C INCLUDES PROBE AND FIXTURE CAPACITANCE
R INCLUDES PROBE AND FIXTURE RESISTANCE
M
M
M
C
M
R
INPUT OPEN
M
V
6
7
5
8
F
V
F
I
1-602
Figure 18. Input-Output Transient Rejection Test Circuit.
OVERSHOOT ON V IS TO BE ≤ 10%
I-O(PEAK)
t
f
r
tdt
dV
I-O
OR
=(0.8) V
I-O (PEAK)
(0.8) V
I-O(PEAK)
t
f
r
t
90%
10%
90%
10%
I-O(PEAK)
V
V
O(OFF)
V (min) ≥ 3.25V
O(OFF)
S AT A (V = 0V)
F
1
V (max) ≤ 0.8
O(ON)
V
O(ON)
S AT B (I = 10mA)
F
1
F
I
HSSR-7110
2
3
4
1
6
7
5
8
I-O
V
_
PULSE
GENERATOR
+
(C INCLUDES PROBE PLUS
FIXTURE CAPACITANCE )
L
O
V
L
C
S
1
V
DD
in
V
B
A
L
R
+
_
F
V
1-603
HERMETIC/HI-REL
OPTOCOUPLERS
Figure 21. Thermal Model.
HSSR-7110
2
3
4
1
6
7
5
8
OS
V
I
F
+
_
+
_
DIGITAL
NANOVOLTMETER
ISOTHERMAL CHAMBER
Figure 19. Voltage Offset Test Setup.
Figure 20. Burn-In Circuit.
2
3
4
1
6
7
5
8
R
IN
V
IN
5.5 V
1.0Ω
R
OUT
V
O
(SEE NOTE)
200Ω
1.0Ω
R
OUT
HSSR-7110
T = LED JUNCTION TEMPERATURE
T = FET 1 JUNCTION TEMPERATURE
T = FET 2 JUNCTION TEMPERATURE
T = FET DRIVER JUNCTION TEMPERATURE
T = CASE TEMPERATURE (MEASURED AT CENTER
OF PACKAGE BOTTOM)
T = AMBIENT TEMPERATURE (MEASURED 6" AWAY
FROM THE PACKAGE)
θ = CASE-TO-AMBIENT THERMAL RESISTANCE
ALL THERMAL RESISTANCE VALUES ARE IN °C/W
C
A
je
jd
jf1
jf2
CA
Tje
CA
θ
104 15
A
T
C
T
jd
T
jf1
T
1515
jf2
T
NOTE:
IN ORDER TO DETERMINE VOUT CORRECTLY, THE CASE TO AMBIENT THERMAL IMPEDANCE MUST
BE MEASURED FOR THE BURN-IN BOARDS TO BE USED. THEN, KNOWING θCA, DETERMINE THE
CORRECT OUTPUT CURRENT PER FIGURES 2 AND 4 TO INSURE THAT THE DEVICE MEETS THE
DERATING REQUIREMENTS AS SHOWN.
1-604
Applications Information
Thermal Model
The steady state thermal model
for the HSSR-7110 is shown in
Figure 21. The thermal resistance
values given in this model can be
used to calculate the temperatures
at each node for a given operating
condition. The thermal resistances
between the LED and other
internal nodes are very large in
comparison with the other terms
and are omitted for simplicity.
The components do, however,
interact indirectly through θCA,
the case-to-ambient thermal
resistance. All heat generated
flows through θCA, which raises
the case temperature TC accord-
ingly. The value of θCA depends on
the conditions of the board design
and is, therefore, determined by
the designer.
The maximum value for each out-
put MOSFET junction-to-case
thermal resistance is specified as
15°C/W. The thermal resistance
from FET driver junction-to-case
is also 15°C/W. The power
dissipation in the FET driver,
however, is negligible in compar-
ison to the MOSFETs.
On-Resistance and Rating
Curves
The output on-resistance, RON,
specified in this data sheet, is the
resistance measured across the
output contact when a pulsed
current signal (IO = 800 mA) is
applied to the output pins. The
use of a pulsed signal (≤ 30 ms)
implies that each junction
temperature is equal to the
ambient and case temperatures.
The steady-state resistance, RSS,
on the other hand, is the value of
the resistance measured across
the output contact when a DC
current signal is applied to the
output pins for a duration
sufficient to reach thermal
equilibrium. RSS includes the
effects of the temperature rise of
each element in the thermal
model.
Rating curves are shown in
Figures 2 and 4. Figure 2 speci-
fies the maximum average output
current allowable for a given
ambient temperature. Figure 4
specifies the output power
dissipation allowable for a given
ambient temperature. Above 55°C
(for θCA = 80°C/W) and 107°C
(for θCA = 40°C/W), the maximum
allowable output current and
power dissipation are related by
the expression RSS = PO(max)/
(IO(max))2 from which RSS can be
calculated. Staying within the safe
area assures that the steady-state
junction temperatures remain less
than 150°C. As an example, for TA
= 95°C and θCA = 80°C/W, Figure
2 shows that the output current
should be limited to less than 610
mA. A check with Figure 4 shows
that the output power dissipation
at TA = 95°C and IO = 610 mA,
will be limited to less than 0.35
W. This yields an RSS of 0.94 Ω.
Design Considerations
for Replacement of
Electro-Mechanical
Relays
The HSSR-7110 family can
replace electro-mechanical relays
with comparable output voltage
and current ratings. The following
design issues need to be consid-
ered in the replacement circuit.
Input Circuit: The drive circuit
of the electro-mechanical relay
coil needs to be modified so that
the average forward current
driving the LED of the HSSR-
7110 does not exceed 20 mA. A
nominal forward drive current of
10 mA is recommended. A
recommended drive circuit with 5
volt VCC and CMOS logic gates is
shown in Figure 1. If higher VCC
voltages are used, adjust the
current limiting resistor to a
nominal LED forward current of
10 mA. One important considera-
tion to note is that when the LED
is turned off, no more than 0.6
volt forward bias should be
applied across the LED. Even a
few microamps of current may be
sufficient to turn on the HSSR-
7110, although it may take a
considerable time. The drive
circuit should maintain at least 5
mA of LED current during the ON
condition. If the LED forward
current is less than the 5 mA
level, it will cause the HSSR-7110
to turn on with a longer delay. In
addition, the power dissipation in
the output power MOSFETs
increases, which, in turn, may
violate the power dissipation
guidelines and affect the
reliability of the device.
Output Circuit: Unlike electro-
mechanical relays, the designer
should pay careful attention to the
output on-resistance of solid state
relays. The previous section, ”On-
Resistance and Rating Curves”
describes the issues that need to
be considered. In addition, for
strictly dc applications the
designer has an advantage using
Connection B which has twice the
1-605
HERMETIC/HI-REL
OPTOCOUPLERS
output current rating as Connec-
tion A. Furthermore, for dc-only
applications, with Connection B
the on-resistance is considerably
less when compared to
Connection A.
Output over-voltage protection is
yet another important design
consideration when replacing
electro-mechanical relays with the
HSSR-7110. The output power
MOSFETs can be protected using
Metal oxide varistors (MOVs) or
TransZorbs against voltage surges
that exceed the 90 volt output
withstand voltage rating.
Examples of sources of voltage
surges are inductive load kick-
backs, lightning strikes, and
electro-static voltages that exceed
the specifications on this data
sheet. For more information on
output load and protection refer
to Application Note 1047.
References:
1. Application Note 1047, ”Low
On-Resistance Solid State
Relays for High Reliability
Applications.”
2. Reliability Data for HSSR-7110.
MOV is a registered trademark of GE/RCA
Solid State.
TransZorb is a registered trademark of
General Semiconductor.
MIL-PRF-38534 Class H
and DESC SMD Test
Program
Hewlett-Packard’s Hi-Rel
Optocouplers are in compliance
with MIL-PRF-38534 Class H.
Class H devices are also in
compliance with DESC drawing
5962-93140.
Testing consists of 100% screen-
ing and quality conformance
inspection to MIL-PRF-38534.
