©2007 Fairchild Semiconductor Corporation

1

www.fairchildsemi.com

1N957B - 1N979B Rev. F1

1N957B - 1N979B

  Zener Diodes

June 2007

1N957B - 1N979B

Zener Diodes

Absolute Maximum Ratings *  

T

A

 = 25

°C unless otherwise noted

* These ratings are limiting values above which the serviceability of the diode may be impaired.

Electrical Characteristics

   

T

A

=25

°C unless otherwise noted

Symbol

Parameter

Value

Units

P

D

Power Dissipation

 

@ TL 

≤ 75 °C, Lead Length = 3/8†�

500

mW

Derate above 75

°C

4.0

mW/

°C

T

J

, T

STG

Operating and Storage Temperature Range

-65 to +200

°C

Device

V

Z

 (Volts)  

(Note 1)

Z

Z

 (

Ω)  

(Note 2)

I

R

 @ V

R

I

ZM

 (mA)

(Note 3)

Min.

Typ.

Max.

@ I

Z

(mA)

Z

Z

 @ I

Z

Z

ZK

 @ I

ZK

μA

Volts

Ω

mA

1N957B
1N958B
1N959B
1N960B
1N961B

6.46

7.125

7.79

8.645

9.5

6.8
7.5
8.2
9.1

10

7.14

7.875

8.61

9.555

10.5

18.5
16.5

15
14

12.5

4.5
5.5
6.5
7.5
8.5

700
700
700
700
700

1.0

 0.5

0.5
0.5

0.25

150

75
50
25
10

5.2
5.7
6.2
6.9
7.6

47
42
38
35
32

1N962B
1N963B
1N964B
1N965B
1N966B

10.45

11.4

12.35
14.25

15.2

11

12
13
15
16

11.55

12.6

13.65
15.75

16.8

11.5

10.5

9.5
8.5
7.8

9.5

11.5

13
16
17

700
700
700
700
700

0.25
0.25
0.25
0.25
0.25

5
5
5
5
5

8.4
9.1
9.9

11.4

12.2

28
26
24
21
19

1N967B
1N968B
1N969B
1N970B
1N971B

17.1

19

20.9
22.8

25.652

18
20
22
24
27

18.9

21

23.1
25.2

28.35

7.0
6.2
5.6
5.2
4.6

21
25
29
33
41

750
750
750
750
750

0.25
0.25
0.25
0.25
0.25

5
5
5
5
5

13.7
15.2
16.7
18.2
20.6

17
15
14
13

11

1N972B
1N973B
1N974B
1N975B
1N976B

8.5

31.35

34.2

37.05
40.85

30
33
36
39
43

31.5

34.65

37.8

40.95
45.15

4.2
3.8
3.4
3.2
3.0

49
58
70
80
93

1000
1000
1000
1000
1500

0.25
0.25
0.25
0.25
0.25

5
5
5
5
5

22.8
25.1
27.4
29.7
32.7

10

9.2
8.5
7.8
7.0

1N977B
1N978B
1N979B

44.65
48.45

53.2

47
51
56

49.35
53.55

58.8

2.7
2.5
2.2

105
125
150

1500
1500
2000

0.25
0.25
0.25

5
5
5

35.8
38.8
42.6

6.4
5.9
5.4

     

DO-35 Glass case

COLOR BAND DENOTES CATHODE

Tolerance = 5%

2

www.fairchildsemi.com

1N957B - 1N979B Rev. F1

1N957B - 1N979B

  Zener Diodes

Notes:
1. Zener Voltage (V

Z

) Measurement

 

Nominal zener voltage is measured with the device junction in the thermal equilibrium at the lead temperature (T

L

) at 30

°C ± 1 °C and 3/8†� lead length.

2. Zener Impedance (Z

Z

) Derivation

Z

ZT

 and Z

ZK

 are measured by dividing the ac voltage drop across the device by the ac current applied. The specified limits are for I

Z(ac)

 = 0.1 I

Z(dc)

 with the ac frequency = 60Hz.

3. Maximum Zener Current Ratings (I

ZM

)

 

The maximum current handling capability on a worst case basis is limited by the actual zener voltage at the operation point and the power derating curve.

Top Mark Information

Device

Line 1

Line 2

Line 3

1N957B
1N958B
1N959B
1N960B
1N961B

LOGO
LOGO
LOGO
LOGO
LOGO

57
58
59
60
61

B
B
B
B
B

1N962B
1N963B
1N964B
1N965B
1N966B

LOGO
LOGO
LOGO
LOGO
LOGO

62
63
64
65
66

B
B
B
B
B

1N967B
1N968B
1N969B
1N970B
1N971B

LOGO
LOGO
LOGO
LOGO
LOGO

67
68
69
70
71

B
B
B
B
B

1N972B
1N973B
1N974B
1N975B
1N976B

LOGO
LOGO
LOGO
LOGO
LOGO

72
73
74
75
76

B
B
B
B
B

1N977B
1N978B
1N979B

LOGO
LOGO
LOGO

77
78
79

B
B
B

3

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1N957B - 1N979B Rev. F1

1N957B - 1N979B

  Zener Diodes

Top Mark Information 

(Continued)

General Requirements:  

1.0 Cathode Band

2.0 First Line: F - Fairchild Logo

3.0 Second Line: Device name - For 1Nxx  series: 4

th

  to  5

th

 characters of the device name.

                                                    For BZxx series: 5

th

 to 6

th

  characters of the device name.

4.0 Third Line: Device name - For 1Nxx series: 6

th

 to 7

th

 characters of the device name.

                                                For BZXyy series: Voltage rating

5.0 Devices shall be marked as required in the device specification (PID or FSC Test Spec).

6.0 Maximum no. of marking lines: 3

7.0 Maximum no. of digits per line: 2

8.0 FSC logo must be 20 % taller than the alphanumeric marking and should occupy the 2 characters of the specified line.

9.0 Marking Font: Arial (Except FSC Logo)

10.0 First character of each marking line must be aligned vertically.

11.0 All device markings must be based on Fairchild device specification.

 

F

22

9B

1

st

 line: F - Fairchild Logo

2

nd

 line: Device Name - 4

th

 to 5

th

 characters of the device name.

or 5

th

 to 6

th

 characters for BZXyy series

3

rd

 line: Device Name - 6

th

 to 7

th

 characters of the device name.

or Voltage rating for BZXyy series

TRADEMARKS

The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is not intended to 
be an exhaustive list of all such trademarks.

1N957B - 1N979B

  Zener Diodes

DISCLAIMER

FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO 
IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE 
OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN;NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE 
RIGHTS OF OTHERS. THESE SPECIFICATIONS DO NOT EXPAND THE TERMS OF FAIRCHILD’S WORLDWIDE TERMS AND CONDITIONS, SPE-
CIFICALLY THE WARRANTY THEREIN, WHICH COVERS THESE PRODUCTS.

LIFE SUPPORT POLICY

FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT 
THE EXPRESS WRITTEN APPROVAL OF FAIRCHILD SEMICONDUCTOR CORPORATION.

As used herein:
1. Life support devices or systems are devices or systems which, (a) are 
intended for surgical implant into the body, or (b) support or sustain life, or 
(c) whose failure to perform when properly used in accordance with 
instructions for use provided in the labeling, can be reasonably expected 
to result in significant injury to the user.

2. A critical component is any component of a life support device or system 
whose failure to perform can be reasonably expected to cause the failure 
of the life support device or system, or to affect its safety or effectiveness.

PRODUCT STATUS DEFINITIONS

Definition of Terms

Datasheet Identification

Product Status

Definition

Advance Information

Formative or In Design

This datasheet contains the design specifications for product develop-
ment. Specifications may change in any manner without notice.

Preliminary

First Production

This datasheet contains preliminary data, and supplementary data will 
be published at a later date.Fairchild Semiconductor reserves the right 
to make changes at any time without notice in order to improve design.

No Identification Needed

Full Production

This datasheet contains final specifications. Fairchild Semiconductor 
reserves the right to make changes at any time without notice in order 
to improve design.

Obsolete

Not In Production

This datasheet contains specifications on a product that has been dis-
continued by Fairchild semiconductor.The datasheet is printed for ref-
erence information only.

GTO™
HiSeC™
i-Lo™
ImpliedDisconnect™
IntelliMAX™
ISOPLANAR™
MICROCOUPLER™
MicroPak™
MICROWIRE™
MSX™
MSXPro™
OCX™
OCXPro™
OPTOLOGIC

®

OPTOPLANAR™

®

PACMAN™
POP™
Power220

®

Power247

®

PowerEdge™

PowerSaver™
PowerTrench

®

Programmable Active Droop™
QFET

®

QS™
QT Optoelectronics™
Quiet Series™
RapidConfigure™
RapidConnect™
ScalarPump™
SMART START™
SPM™
SuperFET™
SuperSOT™-3
SuperSOT™-6
SuperSOT™-8
TCM™
The Power Franchise

®

TinyBoost™

TinyBuck™
TinyLogic

®

TINYOPTO™
TinyPower™
TinyWire™
TruTranslation™
μSerDes™
UHC

®

UniFET™
VCX™
Wire™

ACEx™
Across the board. Around the world.™
ActiveArray™
Bottomless™
Build it Now™
CoolFET™
CROSSVOLT™
CTL™
Current Transfer Logic™
DOME™
E

2

CMOS™

EcoSPARK

®

EnSigna™
FACT Quiet Series™
FACT

®

FAST

®

FASTr™
FPS™
FRFET™
GlobalOptoisolator™

Rev. I23

4

www.fairchildsemi.com

1N957B - 1N979B Rev. F1

1N957B - 1N979B

  Zener Diodes