Semiconductor Components Industries, LLC, 2002
January, 2002 – Rev. 2 1Publication Order Number:
1N4728A/D
1N4728A Series
1 Watt DO-41 Hermetically
Sealed Glass Zener Voltage
Regulator Diodes
This is a complete series of 1 Watt Zener diode with limits and
excellent operating characteristics that reflect the superior capabilities
of silicon–oxide passivated junctions. All this in an axial–lead
hermetically sealed glass package that offers protection in all common
environmental conditions.
Specification Features:
•Zener Voltage Range – 3.3 V to 91 V
•ESD Rating of Class 3 (>16 KV) per Human Body Model
•DO–41 (DO–204AL) Package
•Double Slug Type Construction
•Metallurgical Bonded Construction
•Oxide Passivated Die
Mechanical Characteristics:
CASE: Double slug type, hermetically sealed glass
FINISH: All external surfaces are corrosion resistant and leads are
readily solderable
MAXIMUM LEAD TEMPERATURE FOR SOLDERING PURPOSES:
230°C, 1/16″ from the case for 10 seconds
POLARITY: Cathode indicated by polarity band
MOUNTING POSITION: Any
MAXIMUM RATINGS
Rating Symbol Value Unit
Max. Steady State Power Dissipation
@ TL ≤ 50°C, Lead Length = 3/8″
Derated above 50°C
PD1.0
6.67
Watt
mW/°C
Operating and Storage
Temperature Range TJ, Tstg – 65 to
+200 °C
Devices listed in
bold, italic
are ON Semiconductor
Preferred devices. Preferred devices are recommended
choices for future use and best overall value.
Device Package Shipping
ORDERING INFORMATION (Note 1.)
1N47xxA Axial Lead 2000 Units/Box
1N47xxARL Axial Lead
AXIAL LEAD
CASE 59–10
GLASS
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6000/Tape & Reel
Cathode Anode
1N47xxARL2 Axial Lead 6000/Tape & Reel
1N47xxATA Axial Lead 4000/Ammo Pack
1N47xxATA2 Axial Lead 4000/Ammo Pack
1. The “2” suffix refers to 26 mm tape spacing.
L
1N
47
xxA
YWW
L = Assembly Location
1N47xxA= Device Code
Y = Year
WW = Work Week
Zener Voltage Regulator
IF
V
I
IR
IZT
VR
VZVF
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ELECTRICAL CHARACTERISTICS (TA = 25°C unless
otherwise noted, VF = 1.2 V Max., IF = 200 mA for all types)
Symbol Parameter
VZReverse Zener Voltage @ IZT
IZT Reverse Current
ZZT Maximum Zener Impedance @ IZT
IZK Reverse Current
ZZK Maximum Zener Impedance @ IZK
IRReverse Leakage Current @ VR
VRBreakdown Voltage
IFForward Current
VFForward Voltage @ IF
IrSurge Current @ TA = 25°C
ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise noted, VF = 1.2 V Max, IF = 200 mA for all types)
Zener Voltage (3.)(4.) Zener Impedance (5.) Leakage Current
JEDEC
VZ (Volts) @ IZT ZZT @I
ZT ZZK @I
ZK IR @ VRIr (6.)
JEDEC
Device (2.) Min Nom Max (mA) () () (mA) (µA Max) (Volts) (mA)
1N4728A 3.14 3.3 3.47 76 10 400 1 100 1 1380
1N4729A 3.42 3.6 3.78 69 10 400 1 100 1 1260
1N4730A 3.71 3.9 4.10 64 9 400 1 50 1 1190
1N4731A 4.09 4.3 4.52 58 9 400 1 10 1 1070
1N4732A 4.47 4.7 4.94 53 8 500 1 10 1 970
1N4733A 4.85 5.1 5.36 49 7 550 1 10 1 890
1N4734A 5.32 5.6 5.88 45 5 600 1 10 2 810
1N4735A 5.89 6.2 6.51 41 2 700 1 10 3 730
1N4736A 6.46 6.8 7.14 37 3.5 700 1 10 4 660
1N4737A 7.13 7.5 7.88 34 4 700 0.5 10 5 605
1N4738A 7.79 8.2 8.61 31 4.5 700 0.5 10 6 550
1N4739A 8.65 9.1 9.56 28 5 700 0.5 10 7 500
1N4740A 9.50 10 10.50 25 7 700 0.25 10 7.6 454
1N4741A 10.45 11 11.55 23 8 700 0.25 5 8.4 414
1N4742A 11.40 12 12.60 21 9 700 0.25 5 9.1 380
1N4743A 12.4 13 13.7 19 10 700 0.25 5 9.9 344
1N4744A 14.3 15 15.8 17 14 700 0.25 5 11.4 304
1N4745A 15.2 16 16.8 15.5 16 700 0.25 5 12.2 285
TOLERANCE AND TYPE NUMBER DESIGNATION
2. The JEDEC type numbers listed have a standard tolerance on the nominal zener voltage of ±5%.
SPECIALS AVAILABLE INCLUDE:
3. Nominal zener voltages between the voltages shown and tighter voltage tolerances. For detailed information on price, availability, and
delivery, contact your nearest ON Semiconductor representative.
ZENER VOLTAGE (VZ) MEASUREMENT
4. ON Semiconductor guarantees the zener voltage when measured at 90 seconds while maintaining the lead temperature (TL) at 30°C
± 1°C, 3/8″ from the diode body.
ZENER IMPEDANCE (ZZ) DERIVATION
5. The zener impedance is derived from the 60 cycle ac voltage, which results when an ac current having an rms value equal to 10% of the
dc zener current (IZT or IZK) is superimposed on IZT or IZK.
SURGE CURRENT (IR) NON-REPETITIVE
6. The rating listed in the electrical characteristics table is maximum peak, non-repetitive, reverse surge current of 1/2 square wave or equiv-
alent sine wave pulse of 1/120 second duration superimposed on the test current, IZT, per JEDEC registration; however, actual device
capability is as described in Figure 5 of the General Data – DO-41 Glass.
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ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise noted, VF = 1.2 V Max, IF = 200 mA for all types) (continued)
Zener Voltage (8.)(9.) Zener Impedance (10.) Leakage Current
JEDEC
VZ (Volts) @ IZT ZZT @I
ZT ZZK @I
ZK IR @ VRIr (11.)
JEDEC
Device (7.) Min Nom Max (mA) () () (mA) (µA Max) (Volts) (mA)
1N4746A 17.1 18 18.9 14 20 750 0.25 5 13.7 250
1N4747A 19.0 20 21.0 12.5 22 750 0.25 5 15.2 225
1N4748A 20.9 22 23.1 11.5 23 750 0.25 5 16.7 205
1N4749A 22.8 24 25.2 10.5 25 750 0.25 5 18.2 190
1N4750A 25.7 27 28.4 9.5 35 750 0.25 5 20.6 170
1N4751A 28.5 30 31.5 8.5 40 1000 0.25 5 22.8 150
1N4752A 31.4 33 34.7 7.5 45 1000 0.25 5 25.1 135
1N4753A 34.2 36 37.8 7 50 1000 0.25 5 27.4 125
1N4754A 37.1 39 41.0 6.5 60 1000 0.25 5 29.7 115
1N4755A 40.9 43 45.2 6 70 1500 0.25 5 32.7 110
1N4756A 44.7 47 49.4 5.5 80 1500 0.25 5 35.8 95
1N4757A 48.5 51 53.6 5 95 1500 0.25 5 38.8 90
1N4758A 53.2 56 58.8 4.5 110 2000 0.25 5 42.6 80
1N4759A 58.9 62 65.1 4 125 2000 0.25 5 47.1 70
1N4760A 64.6 68 71.4 3.7 150 2000 0.25 5 51.7 65
1N4761A 71.3 75 78.8 3.3 175 2000 0.25 5 56 60
1N4762A 77.9 82 86.1 3 200 3000 0.25 5 62.2 55
1N4763A 86.5 91 95.6 2.8 250 3000 0.25 5 69.2 50
1N4764A 95 100 105 2.5 350 3000 0.25 5 76 45
TOLERANCE AND TYPE NUMBER DESIGNATION
7. The JEDEC type numbers listed have a standard tolerance on the nominal zener voltage of ±5%.
SPECIALS AVAILABLE INCLUDE:
8. Nominal zener voltages between the voltages shown and tighter voltage tolerances. For detailed information on price, availability, and
delivery, contact your nearest ON Semiconductor representative.
ZENER VOLTAGE (VZ) MEASUREMENT
9. ON Semiconductor guarantees the zener voltage when measured at 90 seconds while maintaining the lead temperature (TL) at 30°C ± 1°C,
3/8″ from the diode body.
ZENER IMPEDANCE (ZZ) DERIVATION
10.The zener impedance is derived from the 60 cycle ac voltage, which results when an ac current having an rms value equal to 10% of the
dc zener current (IZT or IZK) is superimposed on IZT or IZK.
SURGE CURRENT (IR) NON-REPETITIVE
11.The rating listed in the electrical characteristics table is maximum peak, non-repetitive, reverse surge current of 1/2 square wave or equivalent
sine wave pulse of 1/120 second duration superimposed on the test current, IZT, per JEDEC registration; however, actual device capability
is as described in Figure 5 of the General Data – DO-41 Glass.
Figure 1. Power Temperature Derating Curve
TL, LEAD TEMPERATURE (°C)
P
D
0 20 40 60 20080 100 120 140 160 180
0.25
0.5
0.75
1
1.25
L = LEAD LENGTH
TO HEAT SINK
L = 3/8″
L = 1/8″
L = 1″
, MAXIMUM STEADY STATE POWER DISSIPATION (WATTS)
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Figure 2. Temperature Coefficients
(–55°C to +150°C temperature range; 90% of the units are in the ranges indicated.)
a. Range for Units to 12 Volts b. Range for Units to 12 to 100 Volts
+12
+10
+8
+6
+4
+2
0
-2
-4
23456789101112
VZ, ZENER VOLTAGE (VOLTS)
θVZ, TEMPERATURE COEFFICIENT (mV/°C)
100
70
50
30
20
10
7
5
3
2
1
10 20 30 50 70 100
VZ, ZENER VOLTAGE (VOLTS)
θVZ, TEMPERATURE COEFFICIENT (mV/°C)
VZ@IZT
RANGE
RANGE VZ@IZT
Figure 3. Typical Thermal Resistance
versus Lead Length Figure 4. Effect of Zener Current
175
150
125
100
75
50
25
0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
L, LEAD LENGTH TO HEAT SINK (INCHES)
θJL , JUNCTIONTOLEAD THERMAL RESISTANCE (mV/°C/W)
θVZ, TEMPERATURE COEFFICIENT (mV/°C)
+6
+4
+2
0
-2
-4 34 5678
VZ, ZENER VOLTAGE (VOLTS)
VZ@IZ
TA=25°C
20mA
0.01mA
1mA
NOTE: BELOW 3 VOLTS AND ABOVE 8 VOLTS
NOTE: CHANGES IN ZENER CURRENT DO NOT
NOTE: EFFECT TEMPERATURE COEFFICIENTS
Figure 5. Maximum Surge Power
100
70
50
30
20
10
7
5
3
2
1
0.01 0.02 0.05 0.1 0.2 0.5 1 2 5 10 20 50 100 200 500 1000
PW, PULSE WIDTH (ms)
This graph represents 90 percentile data points.
For worst case design characteristics, multiply surge power by 2/3.
Ppk , PEAK SURGE POWER (WATTS)
11V-100V NONREPETITIVE
3.3V-10V NONREPETITIVE
5% DUTY CYCLE
10% DUTY CYCLE
20% DUTY CYCLE
RECTANGULAR
WAVEFORM
TJ=25°C PRIOR TO
INITIAL PULSE
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VF, FORWARD VOLTAGE (VOLTS)
0.4 0.5 0.6 0.7 0.8 0.9 1 1.1
1000
500
200
100
50
20
10
5
2
1
IF, FORWARD CURRENT (mA)
MAXIMUM
150°C
75°C
0°C
25°C
Figure 6. Effect of Zener Current
on Zener Impedance Figure 7. Effect of Zener Voltage
on Zener Impedance
Figure 8. Typical Leakage Current
1000
500
200
100
50
20
10
5
2
1
0.1 0.2 0.5 1 2 5 10 20 50 100
IZ, ZENER CURRENT (mA)
ZZ, DYNAMIC IMPEDANCE (OHMS)
1000
700
500
200
100
70
50
20
10
7
5
2
1
1 2 100
VZ, ZENER VOLTAGE (V)
35710 20305070
ZZ, DYNAMIC IMPEDANCE (OHMS)
10000
7000
5000
2000
1000
700
500
200
100
70
50
20
10
7
5
2
1
0.7
0.5
0.2
0.1
0.07
0.05
0.02
0.01
0.007
0.005
0.002
0.001
IR, LEAKAGE CURRENT (µA)
3456789101112131415
VZ, NOMINAL ZENER VOLTAGE (VOLTS)
+25°C
+125°C
TYPICAL LEAKAGE CURRENT
AT 80% OF NOMINAL
BREAKDOWN VOLTAGE
TJ = 25°C
iZ(rms) = 0.1 IZ(dc)
f = 60 Hz
6.2 V
27 V
VZ = 2.7 V
47 V
TJ = 25°C
iZ(rms) = 0.1 IZ(dc)
f = 60 Hz
20 mA
5 mA
IZ = 1 mA
0 V BIAS
1 V BIAS
400
300
200
100
50
20
10
8
4
1 2 5 10 20 50 100
VZ, NOMINAL VZ (VOLTS)
C, CAPACITANCE (pF)
50% OF BREAKDOWN BIAS
MINIMUM
Figure 9. Typical Capacitance versus VZ
Figure 10. Typical Forward Characteristics
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APPLICATION NOTE
Since the actual voltage available from a given zener
diode is temperature dependent, it is necessary to determine
junction temperature under any set of operating conditions
in order to calculate its value. The following procedure is
recommended:
Lead Temperature, TL, should be determined from:
TL = θLAPD + TA.
θLA is the lead-to-ambient thermal resistance (°C/W) and PD
is the power dissipation. The value for θLA will vary and
depends o n the device mounting method. θLA is generally 30
to 40°C/W for the various clips and tie points in common use
and for printed circuit board wiring.
The temperature of the lead can also be measured using a
thermocouple placed on the lead as close as possible to the
tie point. The thermal mass connected to the tie point is
normally large enough so that it will not significantly
respond to heat surges generated in the diode as a result of
pulsed operation once steady-state conditions are achieved.
Using the measured value of TL, the junction temperature
may be determined by:
TJ = TL + ∆TJL.
∆TJL is the increase in junction temperature above the lead
temperature and may be found as follows:
∆TJL = θJLPD.
θJL may be determined from Figure 3 for dc power
conditions. For worst-case design, using expected limits of
IZ, limits of PD and the extremes of TJ(∆TJ) may be
estimated. Changes in voltage, VZ, can then be found
from:
∆V = θVZ ∆TJ.
θVZ, the zener voltage temperature coefficient, is found
from Figure 2.
Under high power-pulse operation, the zener voltage will
vary with time and may also be affected significantly by the
zener resistance. For best regulation, keep current
excursions as low as possible.
Surge limitations are given in Figure 5. They are lower
than would be expected by considering only junction
temperature, as current crowding effects cause temperatures
to be extremely high in small spots, resulting in device
degradation should the limits of Figure 5 be exceeded.
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OUTLINE DIMENSIONS
1 Watt DO–41 Glass
Zener Voltage Regulator Diodes – Axial Leaded
B
D
K
K
F
F
ADIM MIN MAX MIN MAX
MILLIMETERSINCHES
A4.10 5.200.161 0.205
B2.00 2.700.079 0.106
D0.71 0.860.028 0.034
F--- 1.27--- 0.050
K25.40 ---1.000 ---
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. 59-04 OBSOLETE, NEW STANDARD 59-09.
4. 59-03 OBSOLETE, NEW STANDARD 59-10.
5. ALL RULES AND NOTES ASSOCIATED WITH
JEDEC DO-41 OUTLINE SHALL APPLY
6. POLARITY DENOTED BY CATHODE BAND.
7. LEAD DIAMETER NOT CONTROLLED WITHIN F
DIMENSION.
GLASS
D0–41
CASE 59–10
ISSUE R
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without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular
purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability,
including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or
specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be
validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others.
SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or
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attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim
alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer.
PUBLICATION ORDERING INFORMATION
JAPAN: ON Semiconductor, Japan Customer Focus Center
4–32–1 Nishi–Gotanda, Shinagawa–ku, Tokyo, Japan 141–0031
Phone: 81–3–5740–2700
Email: r14525@onsemi.com
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For additional information, please contact your local
Sales Representative.
1N4728A/D
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