Hutton Close, Crowther Ind Est, Dist 3, Washington, Tyne & Wear NE38 0AH, England
Email: isocom@dial.pipex.com - Tel: +44 0191 4166546 - Fax: +44 0191 4155055
4N55, 4N55/L2, L3, L4
Dual Channel High Speed Hermetically
Sealed Optocoupler
Circuit and Package
Features
Description
Absolute Maximum Ratings
Recommended Operating Conditions
Electrical Characteristics
Typical Characteristics
Radiation Effects Data
Reliability and Approvals
Similar Optocouplers
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Circuit and Package
4N55, 4N55/L2, L3, L4: Optocoupler, 16 Pin Dual Channel High Speed Hermetically Sealed (Datasheet)
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Features
Release to BS9400 GO125
Hermetically Sealed
High Speed: Typically 400 kbit/s
1500 Vdc Withstand Test Voltage
High Radiation Immunity
Performance Guaranteed Over -55°C to +125°C Ambient Temperature Range
2 MHz Bandwidth
Description
The 4N55 consists of two independent optocouplers in a hermetically sealed ceramic package. Each
channel has a light emitting diode and an integrated photon detector. Separate connections for the
photodiodes and output transistor collectors improve the speed up to 100 times that of a conventional
phototransistor optocoupler by reducing the base collector capacitance.
The 4N55 is suitable for wide bandwidth analogue applications, as well as for interfacing TTL to LSTTL
or CMOS. The availability of the base lead allows optimised gain/bandwidth adjustment in analog
applications. The shallow depth of the IC photodiode provides better radiation immunity than
conventional phototransistor couplers. Surface Mount Option Available.
Absolute Maximum Ratings
Storage Temperature:
Operating Temperature:
Lead Soldering:
-65°C to +150°C
-55°C to +125°C
260°C for 10s, 1.6mm from case
Input Diode (each channel)
Peak forward current IF:
Average Forward Current IF:
Reverse Voltage VR:
Power Dissipation:
40mA (duration <= 1ms)
20mA
5V
36mW
Output Detector (each channel)
4N55, 4N55/L2, L3, L4: Optocoupler, 16 Pin Dual Channel High Speed Hermetically Sealed (Datasheet)
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Supply Voltage VCC:
Average Current IO:
Peak Current IO:
Voltage VO:
Emitter-Base Reverse Voltage BVEBO:
Base Current IB:
Power Dissipation:
Derate Linearly:
-0.5V to 20V (1 minute max)
8mA
16mA
-0.5V to 20V
3V
5mA
50mW
1.4mW/°C above 100°C
Recommended Operating Conditions
PARAMETER SYMBOL MIN MAX UNIT
Input Current, Low Level (each channel) IFL 250 µA
Supply Voltage, Output VCC 2 18 V
Electrical Characteristics
(Over recommended temperature Ta= -55°C to +125°C u.o.s.; all typical values at Vcc=5V, Ta=25°C
each channel.)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT NOTES
IOH Logic High Output Current IF=0, VO=VCC=18V,
IF(other channel)=20mA 30 100 µA
1
Output Leakage Current IF=250µA, ... 70 250 µA
ICCL Logic Low Supply Current VCC=18V, IF1,2=20mA 30 200 µA
ICCH Logic High Supply
Current VCC=18V, IF=0mA,
IF(other channel)=20mA 0.4 10 µA
VFInput Forward Voltage IF=20mA 1.45 1.8 V 1
BVRInput Reverse Breakdown
Voltage IR=10µA 3 V
II-O Input-Output Insulation
Leakage Current RH=45%, TA=25°C, t=5s,
VIO=1500Vdc 1.0 µA 3, 9
tPLH Propagation Delay Time to
Logic High at Output RL=8.2kohm, CL=50pF,
IF=16mA, VCC=5V
2.0 6.0 µs 1
tPHL Propagation Delay Time to
Logic Low at Output 0.4 2.0 µs
4N55, 4N55/L2, L3, L4: Optocoupler, 16 Pin Dual Channel High Speed Hermetically Sealed (Datasheet)
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CTR Current Transfer Ratio VO=0.4V, IF=16mA,
VCC=4.5V 9 20 % 1, 2
Typical Characteristics
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT NOTES
dVF/dTATemperature Coefficient
of Forward Voltage IF=20mA -1.9 mV/°C
1
CIN Input Capacitance VF=0, f=1MHz 125 pF
RI-O Resistance (Input-Output) VI-O=500Vdc 1E12 ohm
CI-O Capacitance
(Input-Output) f=1MHz 1.0 pF 1, 4
II-I Input-Input Insulation
Leakage Current RH=45%, VH=500Vdc,
t=5s 1 pA 5
CI-I Capacitance (Input-Input) f=1MHz 0.6 pF
hFE Transistor DC Current
Gain VO=5V, IO=3mA 130 1
dIO/dIFSmall Signal Current
Transfer Ratio VCC=5V, VO=2V 20 %
CMH
Common Mode Transient
Immunity at Logic High
Level Output
VCM=10Vp-p,
RL=8.2kohm, IF=0,
VO(min)=2.0V 1000 V/µs 1, 6
CML
Common Mode Transient
Immunity at Logic Low
Level Output
VCM=10Vp-p,
RL=8.2kohm, IF=16,
VO(max)=0.8V -1000 V/µs 1, 7
BW Bandwidth RL=100ohm 2 MHz 8
Notes
1. Each channel.
2. Current Transfer Ratio is defined as the ratio of output collector current Io to the forward LED input
current If, times 100%. CTR is known to degrade slightly over the unit's lifetime as a function of input
current, temperature, signal duty cycle and system on-time. It is recommended that designers allow at
least 20-25% guardband for CTR degradation.
3. Measured between pins 1 through 8 shorted together and pins 9 through 16 shorted together.
4. Measured between each input pair shorted together and the output pins for that channel shorted
together.
5. Measured between pins 3 and 4 shorted together, and pins 7 and 8 shorted together.
6. CMh is the steepest slope (dV/dt) on the leading edge of the common mode pulse Vcm for which the
output will remain in the logic high state (Vo>2.0V).
4N55, 4N55/L2, L3, L4: Optocoupler, 16 Pin Dual Channel High Speed Hermetically Sealed (Datasheet)
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8. CMl is the steepest slope (dV/dt) on the trailing edge of the common mode pulse Vcm for which the
output will remain in the logic low state (Vo<0.8V).
9. This is a momentary withstand test, not an operation condition.
Radiation Effects Data
Neutron Fluence: Hard to > 3E12n/cm2
Total Dose: Hard to 1 Mrad (Si)
Dose Rate: Hard to 6E9 rad (Si)/sec
Vcc photocurrent up to 1.6A; up to 5µs output transient upset
Reliability and Approvals
Isocom Ltd supplies high reliability devices for applications requiring an operating temperature range of
-55°C to +125°C (e.g. military applications).
Devices supplied have completed rigorous testing, and various high reliability test options are offered.
The Company is developing a suitable specification to permit release to CECC 20000.
As a manufacturer of high reliability optocouplers Isocom Ltd's manufacturing plant in North East
England, has site approval to BS9000 (registered number 1294/M) issued by the British Standards
Institution. Together with CECC, BS9000 is a preferred standard for use in European military projects.
Consequently, Isocom Ltd's approved devices are listed in the CECC "MUAHAG" preferred products
list.
The BS9000 approval is also recognised as meeting the equivalent criteria to those required by
BS5750/ISO9000/EN29000.
The Company's customers can be assured of our commitment to stringent quality, reliability and
inspection standards, as demonstrated by our existing approvals. Other customer-specific options can
also be offered.
Isocom takes great effort to ensure accurate data, but regrettably cannot be held liable for any error on its
website. Visit File Lists to confirm old printouts are up-to-date.
Contents
4N55, 4N55/L2, L3, L4: Optocoupler, 16 Pin Dual Channel High Speed Hermetically Sealed (Datasheet)
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