1N978B

Voltage Temperature Coefficient :
Voltage Tolerance : 5 %
Maximum Reverse Leakage Current : 5 uA
Maximum Zener Impedance : 125 Ohms
Power Dissipation : 500 mW
Maximum Operating Temperature : + 200 C
Mounting Style : Through Hole
Zener Voltage : 51 V
Packaging : Bulk
Package / Case : DO-35
Zener Current : 5.9 mA


Features:

• JEDEC registered 1N957B(-1) to 1N992B(-1) series
• Internal metallurgical bond option available by adding a "-1" suffix
• Also available in JAN, JANTX, and JANTXV qualifications per MIL-PRF-19500/117 by adding the JAN, JANTX, or JANTXV prefixes to part numbers for desired level of screening as well as "-1" suffix; (e.g. JANTX1N962B-1, JANTXV1N986C-1, etc.)
• Military Surface Mount equivalents also available in DO-213AA by adding a UR-1 suffix in addition to the JAN, JANTX, and JANTXV prefix; e.g. JANTX1N962BUR-1 (see separate data sheet)
• Commercial Surface Mount equivalents available as MLL957B to MLL992B or with "-1" suffix for bonded in the DO-213AA MELF style package (consult factory for others)
• DO-7 glass body axial-leaded Zener equivalents are also available

Application

• Regulates voltage over a broad operating 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 per MIL-STD-750 Method 1020
• Minimal capacitance (see Figure 3)
• Inherently radiation hard as described in Microsemi MicroNote 050




Specifications

• Operating and Storage temperature: -65ºC to +175ºC
• Thermal Resistance: 250 ºC/W junction to lead at 3/8 (10 mm) lead length from body, or 310ºC/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 T_L < 50oC 3/8 inch (10 mm) from body or 0.48 W at T_A < 25ºC when mounted on FR4 PC board as described for thermal resistance above (also see Figure1)
• 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)

Description

The popular the 1N978B 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. These glass axial-leaded DO-35 Zeners of the 1N978B are also available with an internal-metallurgical-bond option by adding a "-1" suffix. The 1N962B-1 thru 1N992B-1 are available in JAN, JANTX, and JANTXV military qualifications. Microsemi also offers numerous other Zener products to meet higher and lower power applications.

Parameters:

Technical/Catalog Information	1N978B
Vendor	Fairchild Semiconductor
Category	Discrete Semiconductor Products
Voltage - Zener (Nom) (Vz)	51V
Power - Max	500mW
Impedance (Max) (Zzt)	125 Ohm
Voltage - Forward (Vf) (Max) @ If	-
Current - Reverse Leakage @ Vr	5A @ 38.8V
Tolerance	±5%
Mounting Type	Through Hole, Axial
Package / Case	DO-35, Axial
Packaging	Bulk
Operating Temperature	-65°C ~ 200°C
Lead Free Status	Lead Free
RoHS Status	RoHS Compliant
Other Names	1N978B 1N978B