The document provides information on Vishay's 4N25, 4N26, 4N27, and 4N28 optocouplers, which consist of a gallium arsenide infrared LED and silicon NPN phototransistor in a dual-in-line package. Key features include isolation voltage up to 5000Vrms, interfacing with common logic families, and industry standard packaging. The optocouplers are suitable for applications such as AC mains detection, relay driving, power supply feedback, and logic ground isolation due to their electrical characteristics, agency approvals, and wide operating temperature range from -55°C to 100°C.

1. www.vishay.com For technical questions, contact: optocoupleranswers@vishay.com Document Number: 83725
132 Rev. 1.8, 07-Jan-10
4N25, 4N26, 4N27, 4N28
Vishay Semiconductors
Optocoupler, Phototransistor Output, with Base Connection
DESCRIPTION
The 4N25 family is an industry standard single channel
phototransistor coupler. This family includes the 4N25,
4N26, 4N27, 4N28. Each optocoupler consists of gallium
arsenide infrared LED and a silicon NPN phototransistor.
FEATURES
• Isolation test voltage 5000 VRMS
• Interfaces with common logic families
• Input-output coupling capacitance < 0.5 pF
• Industry standard dual-in-line 6 pin package
• Compliant to RoHS directive 2002/95/EC and
in accordance to WEEE 2002/96/EC
APPLICATIONS
• AC mains detection
• Reed relay driving
• Switch mode power supply feedback
• Telephone ring detection
• Logic ground isolation
• Logic coupling with high frequency noise rejection
AGENCY APPROVALS
• UL1577, file no. E52744
• BSI: EN 60065:2002, EN 60950:2000
• FIMKO: EN 60950, EN 60065, EN 60335
i179004-5
1
2
3
6
5
4
B
C
E
A
C
NC
21842
ORDER INFORMATION
PART REMARKS
4N25 CTR > 20 %, DIP-6
4N26 CTR > 20 %, DIP-6
4N27 CTR > 10 %, DIP-6
4N28 CTR > 10 %, DIP-6
ABSOLUTE MAXIMUM RATINGS (1)
PARAMETER TEST CONDITION SYMBOL VALUE UNIT
INPUT
Reverse voltage VR 5 V
Forward current IF 60 mA
Surge current t ≤ 10 μs IFSM 3 A
Power dissipation Pdiss 100 mW
OUTPUT
Collector emitter breakdown voltage VCEO 70 V
Emitter base breakdown voltage VEBO 7 V
Collector current
IC 50 mA
t ≤ 1 ms IC 100 mA
Power dissipation Pdiss 150 mW

2. Document Number: 83725 For technical questions, contact: optocoupleranswers@vishay.com www.vishay.com
Rev. 1.8, 07-Jan-10 133
4N25, 4N26, 4N27, 4N28
Optocoupler, Phototransistor Output,
with Base Connection
Vishay Semiconductors
Notes
(1) Tamb = 25 °C, unless otherwise specified.
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. Functional operation of the device is not
implied at these or any other conditions in excess of those given in the operational sections of this document. Exposure to absolute
maximum ratings for extended periods of the time can adversely affect reliability.
(2) Refer to reflow profile for soldering conditions for surface mounted devices (SMD). Refer to wave profile for soldering condditions for through
hole devices (DIP).
Notes
(1) Tamb = 25 °C, unless otherwise specified.
Minimum and maximum values are testing requirements. Typical values are characteristics of the device and are the result of engineering
evaluation. Typical values are for information only and are not part of the testing requirements.
(2) JEDEC registered values are 2500 V, 1500 V, 1500 V, and 500 V for the 4N25, 4N26, 4N27, and 4N28 respectively.
COUPLER
Isolation test voltage VISO 5000 VRMS
Creepage distance ≥ 7 mm
Clearance distance ≥ 7 mm
Isolation thickness between emitter and
detector
≥ 0.4 mm
Comparative tracking index DIN IEC 112/VDE 0303, part 1 175
Isolation resistance
VIO = 500 V, Tamb = 25 °C RIO 1012 Ω
VIO = 500 V, Tamb = 100 °C RIO 1011 Ω
Storage temperature Tstg - 55 to + 125 °C
Operating temperature Tamb - 55 to + 100 °C
Junction temperature Tj 125 °C
Soldering temperature (2)
max.10 s dip soldering:
distance to seating plane
≥ 1.5 mm
Tsld 260 °C
ELECTRICAL CHARACTERISTICS (1)
PARAMETER TEST CONDITION PART SYMBOL MIN. TYP. MAX. UNIT
INPUT
Forward voltage (2) IF = 50 mA VF 1.3 1.5 V
Reverse current (2) VR = 3 V IR 0.1 100 μA
Capacitance VR = 0 V CO 25 pF
OUTPUT
Collector base breakdown voltage (2) IC = 100 μA BVCBO 70 V
Collector emitter breakdown voltage (2) IC = 1 mA BVCEO 30 V
Emitter collector breakdown voltage (2) IE = 100 μA BVECO 7 V
ICEO(dark) (2) VCE = 10 V, (base open)
4N25 5 50 nA
4N26 5 50 nA
4N27 5 50 nA
4N28 10 100 nA
ICBO(dark) (2) VCB = 10 V,
(emitter open)
2 20 nA
Collector emitter capacitance VCE = 0 CCE 6 pF
COUPLER
Isolation test voltage (2) Peak, 60 Hz VIO 5000 V
Saturation voltage, collector emitter ICE = 2 mA, IF = 50 mA VCE(sat) 0.5 V
Resistance, input output (2) VIO = 500 V RIO 100 GΩ
Capacitance, input output f = 1 MHz CIO 0.6 pF
ABSOLUTE MAXIMUM RATINGS (1)
PARAMETER TEST CONDITION SYMBOL VALUE UNIT

3. www.vishay.com For technical questions, contact: optocoupleranswers@vishay.com Document Number: 83725
134 Rev. 1.8, 07-Jan-10
4N25, 4N26, 4N27, 4N28
Vishay Semiconductors Optocoupler, Phototransistor Output,
with Base Connection
Note
(1) Indicates JEDEC registered values.
TYPICAL CHARACTERISTICS
Tamb = 25 °C, unless otherwise specified
Fig. 1 - Forward Voltage vs. Forward Current
Fig. 2 - Normalized Non-Saturated and Saturated CTR vs.
LED Current
Fig. 3 - Normalized Non-Saturated and Saturated CTR vs.
LED Current
Fig. 4 - Normalized Non-Saturated and Saturated CTR vs.
LED Current
CURRENT TRANSFER RATIO (1)
PARAMETER TEST CONDITION PART SYMBOL MIN. TYP. MAX. UNIT
DC current transfer ratio VCE = 10 V, IF = 10 mA
4N25 CTRDC 20 50 %
4N26 CTRDC 20 50 %
4N27 CTRDC 10 30 %
4N28 CTRDC 10 30 %
SWITCHING CHARACTERISTICS
PARAMETER TEST CONDITION SYMBOL MIN. TYP. MAX. UNIT
Rise and fall times VCE = 10 V, IF = 10 mA, RL = 100 Ω tr, tf 2 μs
i4n25_01
1001010.1
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
IF
- Forward Current (mA)
VF
-ForwardVoltage(V)
TA
= - 55 °C
TA
= 25 °C
TA
= 85 °C
i4n25_02
0.0
0.5
1.0
1.5
0 10 100
IF
- LED Current (mA)
NCTR
NCTR(SAT)
NCTR-NormalizedCTR
CTRCE(sat)
= 0.4 V
VCE
= 10 V, IF
= 10 mA, TA
= 25 °C
TA
= 25 °C
Normalized to:
1
i4n25_03
1001010.1
0.0
0.5
1.0
1.5
IF
- LED Current (mA)
NCTR-NormalizedCTR
CTRCE(sat)
VCE
= 0.4 V
NCTR
NCTR(SAT)
TA
= 50 °C
Normalized to:
VCE
= 10 V, IF
= 10 mA, TA
= 25 °C
i4n25_04
1001010.1
0.0
0.5
1.0
1.5
IF
- LED Current (mA)
NCTR-NormalizedCTR
NCTR
NCTR(SAT)
TA
= 70 °C
Normalized to:
CTRCE(sat)
VCE
= 0.4 V
VCE
= 10 V, IF
= 10 mA, TA
= 25 °C

4. Document Number: 83725 For technical questions, contact: optocoupleranswers@vishay.com www.vishay.com
Rev. 1.8, 07-Jan-10 135
4N25, 4N26, 4N27, 4N28
Optocoupler, Phototransistor Output,
with Base Connection
Vishay Semiconductors
Fig. 5 - Normalized Non-Saturated and Saturated CTR vs.
LED Current
Fig. 6 - Collector Emitter Current vs.
Temperature and LED Current
Fig. 7 - Collector Emitter Leakage Current vs. Temperature
Fig. 8 - Normalized CTRcb vs. LED Current and Temperature
Fig. 9 - Normalized Photocurrent vs. IF and Temperature
Fig. 10 - Normalized Non-Saturated hFE vs.
Base Current and Temperature
i4n25_05
1001010.1
0.0
0.5
1.0
1.5
IF
- LED Current (mA)
NCTR-NormalizedCTR
NCTR
NCTR(SAT)
TA
= 85 °C
Normalized to:
CTRCE(sat)
VCE
= 0.4 V
VCE
= 10 V, IF
= 10 mA, TA
= 25 °C
i4n25_06
6050403020100
0
5
10
15
20
25
30
35
50 °C
70 °C
85 °C
IF
- LED Current (mA)
ICE
-CollectorCurrent(mA)
25 °C
i4n25_07
100806040200- 20
10- 2
10- 1
100
101
102
103
104
105
Tamb
- Ambient Temperature (°C)
ICEO
-CollectorEmitter(nA)
Typical
VCE
= 10 V
i4n25_08
0.0
0.5
1.0
1.5
25 °C
50 °C
70 °C
IF
- LED Current (mA)
NCTRcb-NormalizedCTRcb
0.1 1 10 100
Normalized to:
VCB
= 9.3 V, IF
= 10 mA, TA
= 25 °C
i4n25_09
0.
0.01
1
1
10
IF
- LED Current (mA)
NormalizedPhotocurrent
0.1 1 10 100
IF
= 10 mA, TA
= 25 °C
Nib, TA
= - 20 °C
Normalized to:
Nib, TA
= 20 °C
Nib, TA
= 50 °C
Nib, TA
= 70 °C
i4n25_10
0.4
0.6
1.0
1.2
Ib - Base Current (µA)
1 10 100 1000
IB
= 20 µA, VCE
= 10 V,
TA
= 25 °C
25 °C
70 °C
- 20 °C
NhFE-NormalizedhFE
0.8
Normalized to:

5. www.vishay.com For technical questions, contact: optocoupleranswers@vishay.com Document Number: 83725
136 Rev. 1.8, 07-Jan-10
4N25, 4N26, 4N27, 4N28
Vishay Semiconductors Optocoupler, Phototransistor Output,
with Base Connection
Fig. 11 - Normalized hFE vs. Base Current and Temperature
Fig. 12 - Propagation Delay vs. Collector Load Resistor
Fig. 13 - Switching Timing
Fig. 14 - Switching Schematic
i4n25_11
0.0
0.5
1.0
1.5
25 °C
- 20 °C
50 °C70 °C
NhFE(sat)-NormalizedSaturatedhFE
1 10 100 1000
VCE
= 10 V, Ib
= 20 µA
TA
= 25 °C
VCE
= 0.4 V
Ib - Base Current (µA)
Normalized to:
i4n25_12
1
10
100
1000
RL
- Collector Load Resistor (kΩ)
tPLH
-PropagationDelay(µs)
2.5
2.0
1.5
1.0
0.1 1 10 100
IF
= 10 mA, TA
= 25 °C
VCC
= 5.0 V, Vth
= 1.5 V
tPLH
tPHL
tPHL
-PropagationDelay(µs)
i4n25_13
IF
tR
= 1.5 V
VO
tD
tS tFtPHL
tPLH
VTH
i4n25_14
VCC = 5 V
f = 10 kHz
DF = 50 %
RL
VO
IF = 10 mA

6. Document Number: 83725 For technical questions, contact: optocoupleranswers@vishay.com www.vishay.com
Rev. 1.8, 07-Jan-10 137
4N25, 4N26, 4N27, 4N28
Optocoupler, Phototransistor Output,
with Base Connection
Vishay Semiconductors
PACKAGE DIMENSIONS in millimeters
PACKAGE MARKING
14771_2
7.12 ± 0.3
0.25
6.5 ± 0.3
1.2 ± 0.1
3.5±0.3
7.62 typ.
0.5 ± 0.1
4.5±0.3
2.8±0.15
4.5 ± 0.3
1 2 3
6 5 4
7.62 to 9.5 typ.
21764-25
4N25
V YWW 24

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Revision: 01-Jan-2019 1 Document Number: 91000
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