LH1550
HIGH VOLTAGE, SOLID STATE RELAY
OPTOCOUPLER
FEATURES
• Normally Open, Single Pole Single Throw Operation
• Control 350 VAC or DC Voltage
• Switch 100 mA Loads
• LED Control Current, 2.5 mA
• Low ON-Resistance, 37
Ω
Typ. at 100 mA
• Isolation Test Voltage, 3750 VAC
RMS
• Current Limit Protection
• Underwriters Lab File # E52744
APPLICATIONS
• Telephone Switch Hook
• High Voltage Test Equipment
• TRIAC Driver
• Motor Control
• Industrial Control Systems
DESCRIPTION
The LH1550 is a single pole single throw (SPST), normally
open (NO), solid state relay. The relay can control AC or
DC loads currents up to 100 mA, with a supply voltage up
to 350 V. The device is packaged in a six pin 0.3 inch dual-
in line package. This package offers an insulation dielec-
tric withstand of 3750 V
RMS
.
The coupler consists of a AlGaAs LED that is optically cou-
pled to a dielectrically isolated photodiode array which
drives two series connected high voltage MOS transistors.
The typical ON-Resistance is 37
Ω
at 25 mA and is linear
up to 50 mA. There is built-in current limiting circuitry in the
detector chip, enabling it to pass FCC 68-302 and other
regulatory voltage surge requirements when over voltage
protection is provided.
Package Dimensions in Inches (mm)
Pin One ID.
3
.248 (6.30)
.256 (6.50)
4
5
6
NC
2
1
A
K
1
2
6
5
S
NC
3
4
.335 (8.50)
.343 (8.70)
.039
(1.00)
Min.
4°
Typ.
.018 (0.45)
.022 (0.55)
S'
.300 (7.62)
Typ.
.130 (3.30)
.150 (3.81)
18° Typ.
.020 (.051) Min.
.031 (0.80)
.035 (0.90)
.100 (2.54) Typ.
.010 (.25)
.014 (.35)
.300 (7.62)
.347 (8.82)
.110 (2.79)
.150 (3.81)
Absolute Maximum Ratings
(T
A
=25
°
C)
Emitter
Reverse Voltage .................................................................. 5.0 V
Continuous Forward Current .............................................50 mA
Peak Forward Current (1
µ
s) ..................................................1 A
Power Dissipation........................................................... 100 mW
Derate Linearly from 25
°
C .......................................... 1.3 mW/
°
C
Detector
Output Breakdown Voltage................................................. 350 V
Continous Load Current ..................................................100 mA
Total Power Dissipation .................................................. 300 mW
Derate Linearly from 25
°
C .......................................See Figure 4
Package
Isolation Test Voltage.............................................3750 VAC
RMS
Power Dissipation........................................................... 400 mW
Derate Linearly from 25
°
C .......................................... 2.5 mW/
°
C
Isolation Resistance
V
IO
=500 V, T
A
=25
°
C....................................................
≥
10
12
Ω
V
IO
=500 V, T
A
=100
°
C...................................................
≥
10
11
Ω
Storage Temperature Range ................................ –40 to +150
°
C
Operating Temperature Range............................... –40 to +85
°
C
Junction Temperature ........................................................ 100
°
C
Soldering Temperature, 2 mm from case, 10 sec. ............ 260
°
C
5–208
Characteristics
(T
A
=25
°
C)
Description
Emitter
Forward Voltage
Reverse Current
Junction Capacitance
Dynamic Resistance
Switching Time
Detector
Output Breakdown Voltage
Output Off-State Leakage Current
Feed through Capacitance, pins 4 to 6
Current Limit
Package
LED Forward Current for Turn-on
LED Forward Current for Turn-off
ON-resistance
Turn-on Time
Turn-off Time
I
FON
I
FOFF
R
ON
t
ON
t
OFF
25
0.2
37
0.8
0.04
50
3.0
3.0
2.5
mA
mA
W
ms
ms
I
L
=100 mA, t=10 ms
V
L
=
±
300 V, I
L
=<5
µ
A
I
F
=5 mA, I
L
=100 mA
I
F
=5 mA, V
L
=+50 V
R
L
=1 k
Ω
V
B
I
T(OFF)
C
T
I
LMT
150
350
380
.03
TBD
190
270
mA
1.0
V
µ
A
I
B
=50
µ
A
V
T
=
±
100 V, I
F
=0 mA
I
F
=0, f=1 KHz,
V
L
=4 VP-P
I
F
=5 mA, t=5 ms
V
F
I
R
C
J
∆
V
F
/
∆
I
F
t
R
, t
F
0.9
1.25
1
15
6
1
1.4
10
V
µ
A
Symbol
Min.
Typ.
Max.
Unit
Test Condition
I
F
=5 mA
V
R
=5 V
V
F
=0 V, f=1 MHz
I
F
=10 mA
I
F
=10 mA
pF
W
µ
s
Figure 1. Timing test circuit
IL
1
I
F
2
NC
3
5
4
NC
6
1 kΩ
Figure 3. LED forward current vs. forward voltage
IF Forward current in mA
120
100
80
60
40
20
0
0.6
0.8 1.0 1.2 1.4 1.6 1.8
VF- Input LED forward Voltage
85°C
25°C
+
–
50 V
Figure 2. Timing waveform
t
R
≤1 µs
Control
Input
Switch
Output
90%
I
F
t
R
≤1 µs
I
L
10%
t
OFF
Figure 4. Recommended load current vs. temperature
IL-Load Current in mA
100
80
60
40
20
0
-40
3.75 mA
>4.5 mA
IF=1.5 mA
t
ON
-20
0
20
40
60
Ambient temperature in
°C
80
5–209
LH1550