FEATURES
3750 Vrms or 5300 Vrms I/O isolation
Current-limit protection built-in
Linear ac/dc operation
High-reliability monolithic receptor
Extremely low leakage current (pA)
High contact off-impedance (G
W
)
Low power consumption (1 mW--12 mW)
Very low switch offset (typically 0.1
m
V)
Logic compatible
Clean, bounce-free switching
Built-in 1 Form C break-before-make
High surge capability
Insensitive to dv/dt
Surface mountable
Compatible with UL1459 and FCC 68.302
UL recognized
CSA certified
BABT certificate of recognition to BS6301
BENEFITS
Long life
Maintenance free
Current-limit SSRs can sustain
repeated faults without damage
Minimizes drive circuitry
Noiseless
Immune to shock
Immune to environmental hazards
such as salt, dirt, and humidity
No arcing
No mounting restrictions
Preapproved for DAA applications
High reliability
Easily configured in series or in parallel
for increased voltage or current
DESCRIPTION
Siemens Solid State Relays (SSRs) are miniature, optically-coupled relays
with high-voltage MOSFET outputs. The relays are capable of switching ac
or dc loads from as little as nanovolts to hundreds of volts. Likewise, the
relays can switch currents in the range of nanoamps to hundreds of milli-
amps. The MOSFET switches are ideal for small signal switching and are
primarily suited for dc or audio frequency applications.
Siemens offers integrated current limiting on many of its relays. If load
current through the relay exceeds the rated value, the relay clamps the
current at a predefined value. If the excessive load current persists, the
limiting circuit has a foldback feature to minimize relay power dissipation.
The current-limit circuit has a multitude of uses. It can be used in tele-
phony to clamp excessive currents emanating from lightning strikes and/
or power-main crosses or in instrumentation and industrial application to
squelch transients from reactive loads. The current-limit circuit also
provides short-circuit protection in power-feed applications.
The SSRs feature a monolithic output die that minimizes wire bonds and
permits easy integration of high-performance circuits such as current
limiting in normally-open switches. The output die contains all the neces-
sary circuitry to perform a relay function, including the photodiode
receptor array, turn-on and turn-off control circuitry, and the MOSFET
switches. The optically-coupled input is controlled by a highly efficient
GaAlAs infrared LED.
Siemens SSRs are available in a 6- or 8-pin through-hole DIP or in gull-
wing surface-mount packages. Some parts are also offered in 8- or 18-pin
small-outline packages (SOPs). The SOPs are size and height compatible
with PCMCIA Type 2 cards. A 0.4 mm distance through insulation spacing
is also available on "H" suffix coded parts. Refer to the Parts Coding
section for a more in-depth description of these parts.
High Voltage Solid State Relays
General Information
Siemens Microelectronics, Inc. Optoelectronics Division
www.smi.siemens.com/opto/
1 of 20
October 1998
Typical Applications
ac Switch
Modems
Telephone
Programmable Controllers
Heater Control
FAX
Light Control
Data Acquisition Systems
Switching Systems
Security Equipment
Voltmeters
Electric Meters
Test Equipment
Ring Relay
Application
Flying Capacitor
Function
Flying Capacitor Switch
Equipment
Data Acquisition Systems
Multiplexers
Scanners
LH1522
LH1522
+
SENSOR
OUTPUT
DATA
OUT
Application
Ring Generators
Function
Square Wave Generator
Equipment
PBX
Central Office Equipment
Ring Generator
LH1513
LH1513
+5 V
20 Hz
dcV
20 Hz
2 dcV P-P ac
+5 V
Typical Applications
(continued)
Service Equipment
Thermostats
E&M Signaling
Answering Machines
Multiplexers
Battery Switch
Scanners
Board Testers
Motor Controls
Gas Pumps
Output Modules
Appliances
RING
GENERATOR
RING
ACCESS
BREAK
SWITCH
(1/2) LH1524
LH1513
RING
ACCESS
LINE
FEED
SECONDARY
PROTECTOR
AT&T LH1150
TIP
RING
GROUND
START
LH1504
(1/2) LH1524
Application
Telephone Line Interface/SLIC
Function
Ring Relay
Break Switch
Ground Start
Test Access
E&M Signalling
Equipment
Subscriber Line Interface
Circuits
PBX
Switching Systems
Test/Service Equipment
LH1516
+5 V
Application
Lamp, Light, Indicator Control
Function
ac Switch
Equipment
Programmable Controllers
Thermostats
Control Panels
Industrial Controls
Siemens Microelectronics, Inc. Optoelectronics Division
Typical Applications
www.smi.siemens.com/opto/
2 of 20
October 1998
Application
Data Access Arrangement (DAA)
Function
Current-Limited Switchhook Control
Equipment
Modems
Security Equipment
Answering Machines
Telephones
FAX
RING
DETECT
ISOLATED
CIRCUITRY
+5 V
TIP
RING
OFF HOOK
RINGDET
LH1525
FUSE
TVS
LH1522
LH1522
LH1522
LH1522
D
E
C
O
D
E
R
P
LOAD
+5 V
Application
Multiplexer
Function
Analog Signal Multiplexer
Analog Input Module
Equipment
Instrumentation
Voltmeters
Test Equipment
Board Testers
Scanners
Data Acquisition Systems
VM
LH1544
LH1544
THERMO-
COUPLER
THERMO-
COUPLER
Application
Thermocouple Switching
Function
Thermocouple Matrix Control
Equipment
Scanners
Data Acquisition Systems
Programmable Controllers
LH1510
TO ALARM
+5 V
SENSOR
OUTPUT
Application
Alarm Switch
Function
Glass Break Indicator
Fire, Smoke Detector
Equipment
Security Systems
Fire/Smoke Alarms
Siemens Microelectronics, Inc. Optoelectronics Division
Typical Applications
www.smi.siemens.com/opto/
3 of 20
October 1998
LH1520
+5 V
DATA
MANIPULATION
AND LOGIC
CONTROL
D
FLIP-FLOP
D
ENABLE
DELAY
Q
HIGH
VOLTAGE
PIEZOELECTRIC
TRANSDUCER
Application
Print Head Driver
Function
Current-Limited Drivers
Piezoelectric Transducer
High-Voltage Print Head
Equipment
Ink Jet Printers
Display Drivers
Thermal Printers
LH1510
LOAD
TRIAC
+
Application
Motor, Light, Heat, Solenoid Control
Function
Triac Predriver
Equipment
Industrial Controls
Programmable Controllers
Factory Automation Equipment
Appliances
RING
DETECT
ISOLATED
CIRCUITRY
A2
(TIP)
B2
(RING)
OFFHOOK
RINGDET
LH1513
FUSE
TVS
LH1536
K2
K1
K3
+5 V
(ASSOCIATED PHONE)
(NORMALLY CLOSED)
A
(TIP)
B
(RING)
(PHONE LINE)
PHONE
LH1536
Application
Talk/Data Switch
Function
On/Off-hook Control
Equipment
Modems
FAX
LH1503
LH1503
LINE 1
LINE 2
TIP
RING
TIP
RING
TIP
RING
MOV
Application
Two-Line PSTN Interface
Function
On/Off-hook Control
Equipment
Telephone Equipment
Test/Service Equipment
Siemens Microelectronics, Inc. Optoelectronics Division
Typical Applications
www.smi.siemens.com/opto/
4 of 20
October 1998
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