Silicon 500 mW Zener Diodes
Microsemi
Scottsdale Division
8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503
Page 1
Copyright © 2005
10-18-2005 REV C
WWW.Microsemi .COM
SCOTTSDALE DIVISION
1N957B thru 1N992B, e3 DO-7
1N957B – 992B, e3 (DO-7 )
DESCRIPTION APPEARANCE
The popular 1N957B thru 1N992B series of 0.5 watt Zener voltage regulators
provides a selection from 6.8 to 200 volts in standard 5% or 10% tolerances
as well as tighter tolerances identified by different suffix letters on the part
number. The somewhat larger DO-7 packaging option offers a “straight-
through” soldered internal connection with a larger active die element than
otherwise provided in the smaller DO-35 package when needed. Microsemi
also offers numerous other Zener products to meet higher and lower power
applications.
DO-7
(DO-204AA)
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
FEATURES
APPLIC ATIONS / BENEFITS
• JEDEC registered 1N957B to 1N992B series
• Internal metallurgical bonding equivalent to “-1” suffix
identification on other military DO-7 Zeners
• Options for screening in accordance with MIL-PRF-
19500 for JAN, JANTX, JANTXV, and JANS are
available by adding MQ, MX, MV, or MSP prefixes
respectively to part numbers.
• Surface mount equivalents in DO-213AA also
available as MLL957B to MLL992B or with “-1” suffix
(consult factory for other surface mount options)
• RoHS Compliant devices avai lable by adding e3 suffix
• Smaller DO-35 glass body axial-leaded Zener
equivalents are also available
• Regulates voltage over a broad op erating current
and temperature range
• Extensive selection from 6.8 to 200 V
• Standard voltage tolerances are plus/minus 5%
with B suffix, 10 % with A suffix identification
• Tight tolerances available in plus or minus 2% or
1% with C or D suffix respectively
• Flexible axial-lead mounting terminals
• Nonsensitive to ESD
• Capacitance also specified (see Figure 3)
• Inherently radiation hard as described in
Microsemi MicroNote 050
MAXIMUM RAT ING S
MECHANICAL AND PACKAGING
• Operating and Storage temperature: -65ºC to +175ºC
• Thermal Resistance: 300 ºC/W junction to lead at 3/8
(10 mm) lead length from body, or 360ºC/W junction
to ambient when mounted on FR4 PC board (1 oz
Cu) with 4 mm2 copper pads and track width 1 mm,
length 25 mm
• Steady-State Power: 0.5 watts at TL < 25oC 3/8 inch
(10 mm) from body or 0.417 W at TA < 25ºC when
mounted on FR4 PC board as described for thermal
resistance above (also see F igure1)
• Forward voltage @200 mA: 1.1 volts (maximum) for
1N957B – 1N985B and 1.3 V for 1N985 – 1N992B
• Solder Temperatures: 260 ºC for 10 s (max)
• CASE: Hermetically sealed axial-lead glass DO-7
(DO-204AA) package
• TERMINALS: Tin-Lead or RoHS Compliant
annealed matte-Tin plating solderable per MIL-
STD-750, method 2026
• POLARITY: Cathode indicated by band. Diode to
be operated with the banded end positive with
respect to the opposite end for Zener regulation
• MARKING: Part number
• TAPE & REEL option: Standard per EIA-296 (add
“TR” suffix to part number)
• WEIGHT: 0.2 grams
• See package dimensions on l ast page
Silicon 500 mW Zener Diodes
WWW.Microsemi .COM
SCOTTSDALE DIVISION
1N957B thru 1N992B, e3 DO-7
1N957B – 992B, e3 (DO-7 )
ELECTRICAL CHARACTERISTICS* @ 25oC
NOMINAL
ZENER
VOLTAGE
(Note 2)
VZ
ZENER
TEST
CURRENT
IZT
MAX. ZENER IMPEDANCE
(Note 3)
ZZT @ IZT ZZK @ IZK
MAX. DC
ZENER
CURRENT
(Note 4)
IZM
MAX. SURGE
CURRENT
(Note 5)
IZSM
MAX. REVERSE
LEAKAGE
CURRENT
IR @ VR
MAX. TEMP.
COEFFICIENT
αVZ
JEDEC
TYPE
NUMBER
(Note 1) VOLTS mA OHMS OHMS mA mA mA μA VOLTS %/oC
1N957B
1N958B
1N959B
1N960B
1N961B
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
1.0
.5
.5
.5
.25
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
+0.05
+0.058
+0.065
+0.068
+0.075
1N962B
1N963B
1N964B
1N965B
1N966B
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
.25
.25
.25
.25
.25
32
31
28
25
24
175
160
150
130
120
5
5
5
5
5
8.4
9.1
9.9
11.4
12.2
+0.076
+0.077
+0.079
+0.082
+0.083
1N967B
1N968B
1N969B
1N970B
1N971B
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
.25
.25
.25
.25
.25
20
18
16
15
13
110
100
90
80
70
5
5
5
5
5
13.7
15.2
16.7
18.2
20.6
+0.085
+0.086
+0.087
+0.088
+0.090
1N972B
1N973B
1N974B
1N975B
1N976B
30
33
36
39
43
4.2
3.8
3.4
3.2
3.0
49
58
70
80
93
1000
1000
1000
1000
1500
.25
.25
.25
.25
.25
12
11
10
9.5
8.8
65
60
55
46
44
5
5
5
5
5
22.8
25.1
27.4
29.7
32.7
+0.091
+0.092
+0.093
+0.094
+0.095
1N977B
1N978B
1N979B
1N980B
1N981B
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
.25
.25
.25
.25
.25
7.9
7.4
6.8
6.0
5.5
40
37
35
30
28
5
5
5
5
5
35.8
38.8
42.6
47.1
51.7
+0.095
+0.096
+0.096
+0.097
+0.097
1N982B
1N983B
1N984B
1N985B
1N986B
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
.25
.25
.25
.25
.25
5.0
4.6
4.1
3.7
3.3
26
23
21
18
16
5
5
5
5
5
56.0
62.2
69.2
76.0
83.6
+0.098
+0.098
+0.099
+0.11
+0.11
1N987B
1N988B
1N989B
1N990B
1N991B
1N992B
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
.25
.25
.25
.25
.25
.25
3.1
2.7
2.4
2.2
2.0
1.8
15
13
12
11
10
9
5
5
5
5
5
5
91.2
98.8
114.0
121.6
136.8
152.0
+0.11
+0.11
+0.11
+0.11
+0.11
+0.11
* JEDEC Registered Data
NOTE 1: The JEDEC type numbers shown (B suffix) have a +/-5% tolerance on nominal Zener voltage. The suffix A is used to identify +/-
10% tolerance; suffix C is used to identify +/-2%; and suffix D is used to identify +/-1% tolerance; no suffix indicates +/-20%
tolerance.
NOTE 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 .375” and .500” from the body. Mounting clips shall be maintained at a
temperature of 25 +8/ -2oC.
NOTE 3: The zener impedance is derived when a 60 cycle ac current having an rms value equal to 10% of the dc zener current (IZT or
IZK) is superimposed 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 variation in dynamic impedance with different zener currents.
NOTE 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 junction temperature 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 75oC lead
temperature at 3/8” from body.
NOTE 5: The surge for IZSM is a square wave or equivalent half-sine wave pulse of 1/120 sec. duration.
Microsemi
Scottsdale Division Page 2
Copyright © 2005
10-18-2005 REV C 8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503
Silicon 500 mW Zener Diodes
WWW.Microsemi .COM
SCOTTSDALE DIVISION
1N957B thru 1N992B, e3 DO-7
1N957B – 992B, e3 (DO-7 )
GRAPHS
TEMPERATURE COEFFICIENT mV/oC
TEMPERATURE COEFFICIENT %/oC
RATED POWER DISSIPATION - mW
Voltage Temperature
Coefficient %/oC
mV Change /oC
T
L – LEAD TEMPERATURE (oC) 3/8” FROM BODY NOMINAL ZENER VOLTAGE (VOLTS)
or TA on FR4 PC BOARD
FIGURE 1 FIGURE 2
POWER DERATING CURVE ZENER VOLTAGE TEMPERATURE
COEFFICIENT vs. ZENER VOLTAGE
PACKAGE DIMEN SIONS
All dimensions in: INCH
Microsemi
Scottsdale Division Page 3
Copyright © 2005
10-18-2005 REV C
FIGURE 3 mm
CAPACITANCE vs. ZENER VOLTAGE
(TYPICAL)
8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503
