Semiconductor Components Industries, LLC, 2001
May, 2001 – Rev. 1 1Publication Order Number:
1N957B/D
1N957B Series
500 mW DO-35 Hermetically
Sealed Glass Zener Voltage
Regulators
This is a complete series of 500 mW Zener diodes 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 – 6.8 V to 75 V
•ESD Rating of Class 3 (>16 KV) per Human Body Model
•DO–204AH (DO–35) Package – Smaller than Conventional
DO–204AA Package
•Double Slug Type Construction
•Metallurgical Bonded Construction
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 (Note 1.)
Rating Symbol Value Unit
Max. Steady State Power Dissipation
@ TL ≤ 75°C, Lead Length = 3/8″
Derate above 75°C
PD500
4.0
mW
mW/°C
Operating and Storage
Temperature Range TJ, Tstg –65 to
+200 °C
1. Some part number series have lower JEDEC registered ratings.
Device Package Shipping
ORDERING INFORMATION
1N9xxB Axial Lead 3000 Units/Box
1N9xxBRL Axial Lead
AXIAL LEAD
CASE 299
GLASS
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5000/Tape & Reel
Cathode Anode
1N9xxBRL2 * Axial Lead 5000/Tape & Reel
1N9xxBRA1 Axial Lead 3000/Ammo Pack
1N9xxBTA Axial Lead 5000/Ammo Pack
* The “2” suffix refers to 26 mm tape spacing.
Polarity band up with cathode lead off first
Polarity band down with cathode lead off first
L
1N
9x
xB
YWW
L = Assembly Location
1N9xxB = Device Code
= (See Table Next Page)
Y = Year
WW = Work Week
1N9xxBTA2 * Axial Lead 5000/Tape & Reel
1N9xxBRR1 Axial Lead 3000/Tape & Reel
1N9xxBRR2 Axial Lead 3000/Tape & Reel
MARKING DIAGRAM
Zener Voltage Regulator
IF
V
I
IR
IZT
VR
VZVF
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ELECTRICAL CHARACTERISTICS (TA = 25°C unless
otherwise noted, VF = 1.5 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
IZM Maximum DC Zener Current
ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise noted, VF = 1.5 V Max @ IF = 200 mA for all types)
Zener Voltage (Note 3.) Zener Impedance (Note 4.) Leakage Current
IZM
Device
Device
VZ (Volts) @ IZT ZZT @ IZT ZZK @ IZK IR @ VR
I
ZM
(Note 5.)
D
ev
i
ce
(Note 2.)
D
ev
i
ce
Marking Min Nom Max mA mA µA Volts mA
1N957B 1N957B 6.46 6.8 7.14 18.5 4.5 700 1.0 150 5.2 47
1N958B 1N958B 7.125 7.5 7.875 16.5 5.5 700 0.5 75 5.7 42
1N959B 1N959B 7.79 8.2 8.61 15 6.5 700 0.5 50 6.2 38
1N960B 1N960B 8.645 9.1 9.555 14 7.5 700 0.5 25 6.9 35
1N961B 1N961B 9.5 10 10.5 12.5 8.5 700 0.25 10 7.6 32
1N962B 1N962B 10.45 11 11.55 11.5 9.5 700 0.25 5 8.4 28
1N963B 1N963B 11.4 12 12.6 10.5 11.5 700 0.25 5 9.1 26
1N964B 1N964B 12.35 13 13.65 9.5 13 700 0.25 5 9.9 24
1N965B 1N965B 14.25 15 15.75 8.5 16 700 0.25 5 11.4 21
1N966B 1N966B 15.2 16 16.8 7.8 17 700 0.25 5 12.2 19
1N967B 1N967B 17.1 18 18.9 7.0 21 750 0.25 5 13.7 17
1N968B 1N968B 19 20 21 6.2 25 750 0.25 5 15.2 15
1N969B 1N969B 20.9 22 23.1 5.6 29 750 0.25 5 16.7 14
1N970B 1N970B 22.8 24 25.2 5.2 33 750 0.25 5 18.2 13
1N971B 1N971B 25.65 27 28.35 4.6 41 750 0.25 5 20.6 11
1N972B 1N972B 28.5 30 31.5 4.2 49 1000 0.25 5 22.8 10
1N973B 1N973B 31.35 33 34.65 3.8 58 1000 0.25 5 25.1 9.2
1N974B 1N974B 34.2 36 37.8 3.4 70 1000 0.25 5 27.4 8.5
1N975B 1N975B 37.05 39 40.95 3.2 80 1000 0.25 5 29.7 7.8
1N978B 1N978B 48.45 51 53.55 2.5 125 1500 0.25 5 38.8 5.9
1N979B 1N979B 53.2 56 58.8 2.2 150 2000 0.25 5 42.6 5.4
1N982B 1N982B 71.25 75 78.75 1.7 270 2000 0.25 5 56 4.1
2. TOLERANCE AND VOLTAGE DESIGNATION
Tolerance designation – Device tolerance of ±5% is indicated by a “B” suffix.
3. ZENER VOLTAGE (VZ) MEASUREMENT
Nominal zener voltage is measured with the device junction in the thermal equilibrium at the lead temperature (TL) at 30°C ± 1°C and 3/8″
lead length.
4. ZENER IMPEDANCE (ZZ) DERIVATION
ZZT and ZZK are measured by dividing the ac voltage drop across the device by the ac current applied. The specified limits are for IZ(ac) =
0.1 IZ(dc) with the ac frequency = 60 Hz.
5. MAXIMUM ZENER CURRENT RATINGS (IZM)
Values shown are based on the JEDEC rating of 400 mW where the actual zener voltage (VZ) is known at the operating point, the maximum
zener current may be increased and is limited by the derating curve.
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0.7
0.6
0.5
0.4
0.3
0.2
0.1
00 20 40 60 80 100 120 140 160 180 200
TL, LEAD TEMPERATURE (°C)
Figure 1. Steady State Power Derating
HEAT
SINKS
3/8" 3/8"
PD, STEADY STATE
POWER DISSIPATION (WATTS)
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APPLICATION NOTE — ZENER VOLTAGE
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 from Figure 2 for dc power:
∆TJL = θJLPD.
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 = θVZTJ.
θVZ, the zener voltage temperature coefficient, is found
from Figures 4 and 5.
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 7. 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 7 be exceeded.
LL
500
400
300
200
100
00 0.2 0.4 0.6 0.8 1
2.4-60V
62-200V
L, LEAD LENGTH TO HEAT SINK (INCH)
JL , JUNCTIONTOLEAD THERMAL RESISTANCE ( C/W)θ°
Figure 2. Typical Thermal Resistance
TYPICAL LEAKAGE CURRENT
AT 80% OF NOMINAL
BREAKDOWN VOLTAGE
+25°C
+125°C
1000
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 3 4 5 6 7 8 910 1112131415
VZ, NOMINAL ZENER VOLTAGE (VOLTS)
I , LEAKAGE CURRENT ( A)µ
R
Figure 3. Typical Leakage Current
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5
+12
+10
+8
+6
+4
+2
0
-2
-4 2345 678 9101112
VZ, ZENER VOLTAGE (VOLTS)
Figure 4a. Range for Units to 12 Volts
VZ@IZT
(NOTE 2)
RANGE
TEMPERATURE COEFFICIENTS
(–55°C to +150°C temperature range; 90% of the units are in the ranges indicated.)
100
70
50
30
20
10
7
5
3
2
1
2 3 4 5 6 7 8 9 10 11 12 10 20 30 50 70 100
VZ, ZENER VOLTAGE (VOLTS)
Figure 4b. Range for Units 12 to 100 Volts
RANGE VZ@IZ(NOTE 2)
120 130 140 150 160 170 180 190 200
200
180
160
140
120
100
VZ, ZENER VOLTAGE (VOLTS)
Figure 4c. Range for Units 120 to 200 Volts
VZ@IZT
(NOTE 2)
+6
+4
+2
0
-2
-4
3 4 56 78
VZ, ZENER VOLTAGE (VOLTS)
Figure 5. Effect of Zener Current
NOTE: BELOW 3 VOLTS AND ABOVE 8 VOLTS
NOTE: CHANGES IN ZENER CURRENT DO NOT
NOTE: AFFECT TEMPERATURE COEFFICIENTS
1mA
0.01mA
VZ@IZ
TA=25°C
1000
C, CAPACITANCE (pF)
500
200
100
50
20
10
5
2
1
1 2 5 10 20 50 100
VZ, ZENER VOLTAGE (VOLTS)
Figure 6a. Typical Capacitance 2.4–100 Volts
TA=25°C
0V BIAS
1V BIAS
50% OF
VZBIAS
100
70
50
30
20
10
7
5
3
2
1
120 140 160 180 190 200 220
VZ, ZENER VOLTAGE (VOLTS)
Figure 6b. Typical Capacitance 120–200 Volts
TA=25°C
1VOLTBIAS
50% OF VZBIAS
0 BIAS
θVZ, TEMPERATURE COEFFICIENT (mV/°C)
20mA
C, CAPACITANCE (pF) θVZ, TEMPERATURE COEFFICIENT (mV/°C)θVZ, TEMPERATURE COEFFICIENT (mV/°C)
θVZ, TEMPERATURE COEFFICIENT (mV/°C)
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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
Ppk , PEAK SURGE POWER (WATTS)
PW, PULSE WIDTH (ms)
5% DUTY CYCLE
10% DUTY CYCLE
20% DUTY CYCLE
11V-91V NONREPETITIVE
1.8V-10V NONREPETITIVE
RECTANGULAR
WAVEFORM
TJ=25°C PRIOR TO
INITIAL PULSE
Figure 7a. Maximum Surge Power 1.8–91 Volts
1000
700
500
300
200
100
70
50
30
20
10
7
5
3
2
1
0.01 0.1 1 10 100 1000
Ppk , PEAK SURGE POWER (WATTS)
PW, PULSE WIDTH (ms)
Figure 7b. Maximum Surge Power DO-204AH
100–200 Volts
1000
500
200
100
50
20
10
1
2
5
0.1 0.2 0.5 1 2 5 10 20 50 100
IZ, ZENER CURRENT (mA)
Figure 8. Effect of Zener Current on
Zener Impedance
ZZ, DYNAMIC IMPEDANCE (OHMS)
ZZ, DYNAMIC IMPEDANCE (OHMS)
1000
700
500
200
100
70
50
20
10
7
5
2
1
1 2 3 5 7 10 20 30 50 70 100
VZ, ZENER VOLTAGE (VOLTS)
Figure 9. Effect of Zener Voltage on Zener Impedance Figure 10. Typical Forward Characteristics
RECTANGULAR
WAVEFORM, TJ=25°C
100-200VOLTS NONREPETITIVE
TJ=25°C
iZ(rms)=0.1 IZ(dc)
f=60Hz
IZ=1mA
5mA
20mA
TJ=25°C
iZ(rms)=0.1 IZ(dc)
f=60Hz
VZ=2.7V
47V
27V
6.2V
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)
MINIMUM
MAXIMUM
150°C
75°C
0°C
25°C
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Figure 11. Zener Voltage versus Zener Current — VZ = 1 thru 16 Volts
VZ, ZENER VOLTAGE (VOLTS)
IZ, ZENER CURRENT (mA)
20
10
1
0.1
0.01
1 23456 78 910111213141516
TA=25°
Figure 12. Zener Voltage versus Zener Current — VZ = 15 thru 30 Volts
VZ, ZENER VOLTAGE (VOLTS)
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
10
1
0.1
0.01
TA=25°
IZ, ZENER CURRENT (mA)
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Figure 13. Zener Voltage versus Zener Current — VZ = 30 thru 105 Volts
VZ, ZENER VOLTAGE (VOLTS)
10
1
0.1
0.01
30 35 40 45 50 55 60 70 75 80 85 90 95 100
Figure 14. Zener Voltage versus Zener Current — VZ = 110 thru 220 Volts
VZ, ZENER VOLTAGE (VOLTS)
110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260
10
1
0.1
0.01
TA=25°
65 105
IZ, ZENER CURRENT (mA)IZ, ZENER CURRENT (mA)
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OUTLINE DIMENSIONS
500 mW DO–35 Glass
Zener Voltage Regulators – Axial Leaded
GLASS DO–35/D0–204AH
CASE 299–02
ISSUE A
NOTES:
1. PACKAGE CONTOUR OPTIONAL WITHIN A AND B
HEAT SLUGS, IF ANY, SHALL BE INCLUDED
WITHIN THIS CYLINDER, BUT NOT SUBJECT TO
THE MINIMUM LIMIT OF B.
2. LEAD DIAMETER NOT CONTROLLED IN ZONE F
TO ALLOW FOR FLASH, LEAD FINISH BUILDUP
AND MINOR IRREGULARITIES OTHER THAN
HEAT SLUGS.
3. POLARITY DENOTED BY CATHODE BAND.
4. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
All JEDEC dimensions and notes apply.
DIM MIN MAX MIN MAX
INCHESMILLIMETERS
A3.05 5.08 0.120 0.200
B1.52 2.29 0.060 0.090
D0.46 0.56 0.018 0.022
F--- 1.27 --- 0.050
K25.40 38.10 1.000 1.500
B
D
K
K
F
F
A
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Notes
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Notes
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1N957B/D
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