T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 1 of 8
1N957B-1 – 1N992B-1
Availa ble on
commercial
versions
Silicon 500 mW Zener Diodes
Qualified per MIL-PRF-19500/117
Qualified Levels*:
JAN, JANTX, and
JANTXV
DESCRIPTION
The popular 1N957B-1 through 1N992B-1 series of 0.5 watt Zener voltage regulators provides
a selection from 6.8 to 200 volts in a standard 5%, 2% and 1% tolerance versions. These
axial-leaded glass DO-35 Zeners feat ure an internal metal lurg ic al bond and are available in
military qualified and commercial RoHS compliant versions. Milit ary qualified ver si ons are
available on the 1N962B-1 through 1N992B-1 range of part numbers.
DO-35 (DO-204AH)
Package
Also available in:
DO-213AA package
(MELF surface mount)
1N957BUR-1 –
1N992BUR-1
Important: For the latest information, visit our website http://www.microsemi.com.
FEATURES
• JEDEC registered 1N957B to 1N 992B number series.
• Interna l meta llurg ic al bond.
• *JAN, JANTX, and JANTXV qualifications are available per MIL-PRF-19500/117 for part numbers
1N962B-1 thru 1N992B-1.
• Upscreening is available in reference to MIL-PRF-19500 for the range of 1N957B-1 through
1N961B-1.
(See part nomenclature for all available options.)
• RoHS compliant versions available ( co mme rci al grade only ).
APPLICATIONS / BENEFITS
• Regulates voltage over a broad operating current and temperature range.
• Extensive selection from 6.8 to 200 V.
• Standard voltage tolerance is ± 5% with optional tighter tolerances of ± 2% or 1%.
• Flexible axial-lea d mount ing te rmina ls.
• Non-sensitive to ESD per MIL-STD-750 method 1020.
• Minimal capacitance.
• Inherently radiation hard as described in M icros emi MicroNote 050.
MAXIMUM RATINGS
MSC – Lawrence
6 Lake Street,
Lawrence, MA 01841
Tel: 1-800-446-1158 or
(978) 620-2600
Fax: (978) 689-0803
MSC – Ireland
Gort Road Business Park,
Ennis, Co. Clare, Ireland
Tel: +353 (0) 65 6840044
Fax: +353 (0) 65 6822298
Website:
www.microsemi.com
Parameters/Test Conditions
Symbol
Value
Unit
Operating and Storage Temperature
TJ and TSTG
-65 to +175
ºC
Thermal Resi stan ce Jun cti on-to-Lead
@ .375 inch (9.53 m m) lead length fr om body
R
ӨJL
250
ºC/W
Thermal Resi stan ce Jun cti on-to-Ambient when
mounted on PCB
(1)
R
ӨJA
300
ºC/W
Steady-State Power Dissipation
@ TL = +50°C .375 inch (9.53 mm) from body (2)
@ TA = 55°C mounted on PCB
PD
0.5
0.4
W
Forward Voltage @ I
F
= 200 mA
1N957 – 1N985
1N986 – 1N992
VF
1.1
1.3
V
Solder Temperature @ 10 s
TSP
260
oC
NOTES: 1. See figures 1 and 2 for derating curves. TA = +75°C on an FR4 PC board with 1 oz copper
metalization.
2. Both ends of case or diode body to heat sink at L = .375 inch (9.53 mm). Derate IZ to 0.0 mA at
+175°C.
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 2 of 8
1N957B-1 – 1N992B-1
MECHANICAL and PACKAGING
• CASE: Hermetically sealed axial-lead gla ss DO-35 (DO-204 AH) package.
• TERMINALS: Tin-lead (Sn/Pb) or RoHS compliant annealed matte-tin plat ing (on commercial grade only ). Solderable per MIL-
STD-750, method 2026.
• MARKING: Part number.
• POLARITY: Cathode indicated by band. Diode to be operated with the banded end positive with respect to the opposite end for
Zener regulation.
• TAPE & REEL option: Standard per EIA-296 (add “TR” suffix to part number). Consult factory for quantities.
• WEIGHT: 0.2 grams
• See Package Dimensions on last page.
PART NOMENCLATURE
1N957B-1 – 1N961B-1 only:
1N957 B -1 (e3)
(see Electrical Characteristics
table)
Zener Voltage Tolerance
B = 5%
C = 2%
RoHS Compli ance
e3 = RoHS compliant
Blank = non-RoHS compliant
Metallurgically Bonded
1N962B-1 – 1N992B-1 on ly :
JAN 1N962 B -1 (e3)
JAN = JAN level
JANTX = JANTX level
JANTXV = J ANTXV level
Blank = Commercial
JEDEC type number
(see Electrical Characteristics
table)
Zener Voltage Tolerance
B = 5%
C = 2%
RoHS Compli ance
e3 = RoHS compliant (available
on commercial grade only)
Blank = non-RoHS compliant
Metallurgically Bonded
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 3 of 8
1N957B-1 – 1N992B-1
SYMBOLS & DEFINITIONS
Symbol
Definition
IR
Reverse Current: The maximum reverse (leakage) current that will flow at the specified voltage and temperature.
IZ, IZT, IZK
Regulator Current: The dc regulator current (IZ), at a specified test point (IZT), near breakdown knee (IZK).
IZM
Maximum Regulator (Zener) Current: The maximum rated dc current for the specified power rating.
IZSM
Maximum Zener Surge Current: The non-repetitive peak value of Zener surge current at a specified wave form.
VF
Maximum Forward Voltage: The maximum forward voltage the device will exhibit at a specified current.
V
R
Reverse Voltage: The reverse voltage dc value, no alternating component.
VZ
Zener Voltage: The Zener voltage the device will exhibit at a specified current (IZ) in its breakdown region.
ZZT o r ZZK
Dynamic Impedance: The small signal impedance of the diode when biased to operate in its breakdown region at a
specified rms current modulation (typically 10% of IZT or IZK) and superimpos ed on IZT or IZK respectively.
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 4 of 8
1N957B-1 – 1N992B-1
ELECTRICAL CHARACTERISTICS
JEDEC TYPE
NUMBER
(NOTE 1)
NOMINAL
ZENER
VOLTAGE
(NOTE 2)
VZ
ZENER
TEST
CURRENT
IZT
MAXIMUM ZENER
IMPEDANCE
ZZT
ZZ ZZK @ IZK
MAXIM UM DC
ZENER
CURRENT
(NOTE 4)
IZM
MAXIMUM
SURGE
CURRENT
(NOTE 5)
IZSM
MAXIMUM
REVERSE
LEAKAGE
CURRENT
IR @ VR
MAXIMUM
TEMPERATURE
COEFFICIENT
α
VZ
Volts
mA
Ohms
Ohms
µA
mA
mA
µA
Volts
%/°C
1N957B-1
1N958B-1
1N959B-1
1N960B-1
1N961B-1
6.8
7.5
8.2
9.1
10
18.5
16.5
15.0
14.0
12.5
4.5
5.5
6.5
7.5
8.5
700
700
700
700
700
250
250
250
250
250
55
50
45
41
38
300
275
250
225
200
150
75
50
25
10
5.2
5.7
6.2
6.9
7.6
+0.050
+0.058
+0.065
+0.068
+0.075
1N962B-1
1N963B-1
1N964B-1
1N965B-1
1N966B-1
11
12
13
15
16
11.5
10.5
9.5
8.5
7.8
9.5
11.5
13.0
16
17
700
700
700
700
700
250
250
250
250
250
35
32
30
26
25
590
540
500
433
406
1.0
1.0
0.5
0.5
0.5
8.4
9.1
9.9
11
12
+0.073
+0.076
+0.079
+0.082
+0.083
1N967B-1
1N968B-1
1N969B-1
1N970B-1
1N971B-1
18
20
22
24
27
7.0
6.2
5.6
5.2
4.6
21
25
29
33
41
750
750
750
750
750
250
250
250
250
250
21
19
17
16
14
361
325
295
271
240
0.5
0.5
0.5
0.5
0.5
14
15
17
18
21
+0.085
+0.086
+0.087
+0.088
+0.090
1N972B-1
1N973B-1
1N974B-1
1N975B-1
1N976B-1
30
33
36
39
43
4.2
3.8
3.4
3.2
3.0
49
58
70
80
93
1000
1000
1000
1000
1000
250
250
250
250
250
13
12
11
9.1
8.8
216
197
180
166
151
0.5
0.5
0.5
0.5
0.5
23
25
27
30
33
+0.091
+0.092
+0.093
+0.094
+0.095
1N977B-1
1N978B-1
1N979B-1
1N980B-1
1N981B-1
47
51
56
62
68
2.7
2.5
2.2
2.0
1.8
105
125
150
185
230
1500
1500
2000
2000
2000
250
250
250
250
250
7.9
7.4
6.9
6.0
5.5
138
127
116
105
95
0.5
0.5
0.5
0.5
0.5
36
39
43
47
52
+0.095
+0.096
+0.096
+0.097
+0.097
1N982B-1
1N983B-1
1N984B-1
1N985B-1
1N986B-1
75
82
91
100
110
1.7
1.5
1.4
1.3
1.1
270
330
400
500
750
2000
3000
3000
3000
4000
250
250
250
250
250
5.1
4.6
4.2
3.7
3.3
86
79
71
65
59
0.5
0.5
0.5
0.5
0.5
56
62
69
76
84
+0.098
+0.098
+0.099
+0.110
+0.110
1N987B-1
1N988B-1
1N989B-1
1N990B-1
1N991B-1
1N992B-1
120
130
150
160
180
200
1.0
0.95
0.85
0.80
0.68
0.65
900
1100
1500
1700
2200
2500
4500
5000
6000
6500
7100
8000
250
250
250
250
250
250
3.1
2.7
2.4
2.2
2.0
1.8
54
50
43
40
36
32
0.5
0.5
0.5
0.5
0.5
0.5
91
99
114
122
137
152
+0.110
+0.110
+0.110
+0.110
+0.110
+0.110
NOTES:
1. The JEDEC type numbers shown (B suffix) have a ± 5% tolerance on nominal Zener voltage. Th e suffix C will have ± 2% tolerance; and suffix
D will have ± 1% tolerance.
2. Zener voltage (VZ) is measured after the test current has been applied for 20 ± 5 seconds. The device shall be suspended by its leads with
the inside edge of the mounting clips between 0.375” and 0.500” from the body. Mounting clips shall be maint ai ned at temperat ure of 25 ± 8/ -
2 °C.
3. The Zener im pedance is derived when a 60 cycle ac current having an rms value equal to 10% of the dc Zener current (IZT or IZK) is
superimpos ed on IZT or IZK. Zener impedance is measured at 2 points to ensure a sharp knee on the breakdown curve and to eliminate
unstable units. See MicroNote 202 for variat i on in dynamic impedance with dif ferent Zener currents.
4. The values of IZM are calculated for a ± 5% tolerance on nominal Zener voltage. Allowance has been made for the rise in Zener voltage above
VZT which results from Zener impedance and the increase in juncti on tem perat ure as power dissipation approaches 400 mW. In the case of
individual diodes IZM is that value of current which results in a dissipation of 400 mW at 75°C lead temperature at 3/8” from body.
5. The surge for IZSM is a square wave or equivalent half-sine wave pulse of 1/120 sec. duration.
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 5 of 8
1N957B-1 – 1N992B-1
GRAPHS
TL (ºC) (Leads .375”)
FIGURE 1
Temperature-Power Derating Curve
TL (ºC) (PCB)
FIGURE 2
Temperature-Power Derating Curve (PCB mount)
DC Operations Maximum Rating (mW)
DC Operations Maximum Rating (mW)
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 6 of 8
1N957B-1 – 1N992B-1
GRAPHS
Time (s)
FIGURE 3
Therm al Impedanc e PC B mount
Time (s)
FIGURE 4
Thermal Impedance
Theta (°C/W)
Theta (°C/W)
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 7 of 8
1N957B-1 – 1N992B-1
GRAPHS
LEAD TEMPERATURE (ºC)
(At described lead length)
Inches
Millimeters
.000
0.00
.125
3.18
.250
6.35
.375
9.53
FIGURE 5
Maximum Power vs Lead Temperature And Lead Length.
MAXIMUM POWER DISSIPATION (mW )
T4-LDS-0287, Rev. 1 (121795) ©2012 Microsemi Corporation Page 8 of 8
1N957B-1 – 1N992B-1
PACKAGE DIMENSIONS
Ltr
Dimensions
Notes
Inch
Millimeters
Min
Max
Min
Max
BD
.055
.090
1.40
2.29
3
BL
.120
.200
3.05
5.08
3
LD
.018
.022
0.46
0.56
LL
1.000
1.500
25.40
38.10
LL1
.050
1.27
4
NOTES:
1. Dimensions are in inch.
2. Millimeters are given for general information only.
3. Package contour optional within BD and length BL. Heat slugs, if any, shall be included within this cylinder
but shall not be subject to minimum limit of LD. The BL dimension shall include the entire body including
slugs.
4. Within LL1 lead, diameter may vary to allow for for flash, lead finish build-up, and minor irregularities other
than heat slugs.
5. In accordance with ASME Y14.5M, diameters are equivalent to Φx symbology.