MOTOROLA
SEMICONDUCTOR
TECHNICAL DATA
500 mW DO-35 Glass
Zener Voltage Regulator Diodes
GENERAL DATA APPLICABLE TO ALL SERIES IN
THIS GROUP
1N746A
SERIES
500 mW
DO-35 GLASS
GLASS ZENER DIODES
500 MILLIWATTS
1.8–200 VOLTS
500 Milliwatt
Hermetically Sealed
Glass Silicon Zener Diodes
Specification Features:
•
Complete Voltage Range — 1.8 to 200 Volts
•
DO-204AH Package — Smaller than Conventional DO-204AA Package
•
Double Slug Type Construction
•
Metallurgically Bonded Construction
Mechanical Characteristics:
CASE:
Double slug type, hermetically sealed glass
MAXIMUM LEAD TEMPERATURE FOR SOLDERING PURPOSES:
230°C, 1/16″ from
case for 10 seconds
FINISH:
All external surfaces are corrosion resistant with readily solderable leads
POLARITY:
Cathode indicated by color band. When operated in zener mode, cathode
will be positive with respect to anode
MOUNTING POSITION:
Any
WAFER FAB LOCATION:
Phoenix, Arizona
ASSEMBLY/TEST LOCATION:
Seoul, Korea
MAXIMUM RATINGS
(Motorola Devices)*
Rating
DC Power Dissipation and TL
≤
75°C
Lead Length = 3/8″
Derate above TL = 75°C
Operating and Storage Temperature Range
* Some part number series have lower JEDEC registered ratings.
CASE 299
DO-204AH
GLASS
Symbol
PD
Value
500
4
Unit
mW
mW/°C
°C
TJ, Tstg
– 65 to +200
PD , MAXIMUM POWER DISSIPATION (WATTS)
0.7
0.6
0.5
0.4
3/8”
3/8”
HEAT
SINKS
0.3
0.2
0.1
0
0
20
40
60
80
100
120
140
160
180 200
TL, LEAD TEMPERATURE (°C)
Figure 1. Steady State Power Derating
Motorola TVS/Zener Device Data
500 mW DO-35 Glass Data Sheet
6-1
GENERAL DATA — 500 mW DO-35 GLASS
ELECTRICAL CHARACTERISTICS
(TA = 25°C, VF = 1.5 V Max at 200 mA for all types)
Nominal
Zener Voltage
VZ @ IZT
(Note 2)
Volts
Test
Current
IZT
mA
Maximum Zener Impedance
ZZT @ IZT
(Note 3)
Ohms
Maximum
DC Zener Current
IZM
(Note 4)
mA
Maximum Reverse Leakage Current
TA = 25°C
IR @ VR = 1 V
µA
TA = 150°C
IR @ VR = 1 V
µA
Type
T
Number
(Note 1)
1N746A
1N747A
1N748A
1N749A
1N750A
1N751A
1N752A
1N753A
1N754A
1N755A
1N756A
1N757A
1N758A
1N759A
3.3
3.6
3.9
4.3
4.7
5.1
5.6
6.2
6.8
7.5
8.2
9.1
10
12
20
20
20
20
20
20
20
20
20
20
20
20
20
20
28
24
23
22
19
17
11
7
5
6
8
10
17
30
110
100
95
85
75
70
65
60
55
50
45
40
35
30
10
10
10
2
2
1
1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
30
30
30
30
30
20
20
20
20
20
20
20
20
20
NOTE 1. TOLERANCE AND VOLTAGE DESIGNATION
Tolerance Designation
The type numbers shown have tolerance designations as follows:
1N4370A series:
±5%
units, C for
±2%,
D for
±1%.
1N746A series:
±5%
units, C for
±2%,
D for
±1%.
1N957B series:
±5%
units, C for
±2%,
D for
±1%.
NOTE 2. ZENER VOLTAGE (VZ) MEASUREMENT
Nominal zener voltage is measured with the device junction in thermal equilibrium at the lead
temperature of 30°C
±1°C
and 3/8″ lead length.
NOTE 3. 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.
NOTE 4. 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.
500 mW DO-35 Glass Data Sheet
6-2
Motorola TVS/Zener Device Data
GENERAL DATA — 500 mW DO-35 GLASS
APPLICATION NOTE — ZENER VOLTAGE
Since the actual voltage available from a given zener diode
is temperature dependent, it is necessary to determine junc-
tion temperature under any set of operating conditions in order
to calculate its value. The following procedure is recom-
mended:
Lead Temperature, TL, should be determined from:
TL =
θ
LAPD + TA.
θ
LA is the lead-to-ambient thermal resistance (°C/W) and PD is
the power dissipation. The value for
θ
LA will vary and depends
on the device mounting method.
θ
LA 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 mea-
sured value of TL, the junction temperature may be deter-
mined by:
TJ = TL +
∆T
JL.
∆T
JL is the increase in junction temperature above the lead
temperature and may be found from Figure 2 for dc power:
∆T
JL =
θ
JLPD.
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
=
θ
VZTJ.
θ
VZ, 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 ex-
tremely high in small spots, resulting in device degradation
should the limits of Figure 7 be exceeded.
θ
JL , JUNCTION-TO-LEAD THERMAL RESISTANCE (
°
C/W)
500
400
L
L
300
2.4–60 V
200
100
0
62–200 V
0
0.2
0.4
0.6
0.8
1
L, LEAD LENGTH TO HEAT SINK (INCH)
Figure 2. Typical Thermal Resistance
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
9
10
11
12
13
14
15
+25°C
TYPICAL LEAKAGE CURRENT
AT 80% OF NOMINAL
BREAKDOWN VOLTAGE
I R , LEAKAGE CURRENT (
µ
A)
+125°C
VZ, NOMINAL ZENER VOLTAGE (VOLTS)
Figure 3. Typical Leakage Current
Motorola TVS/Zener Device Data
500 mW DO-35 Glass Data Sheet
6-3
GENERAL DATA — 500 mW DO-35 GLASS
TEMPERATURE COEFFICIENTS
(–55°C to +150°C temperature range; 90% of the units are in the ranges indicated.)
θV
Z , TEMPERATURE COEFFICIENT (mV/
°C)
+12
+10
+8
+6
+4
+2
RANGE
0
–2
–4
2
3
4
5
6
7
8
9
VZ, ZENER VOLTAGE (VOLTS)
10
11
12
VZ @ IZT
(NOTE 2)
θV
Z , TEMPERATURE COEFFICIENT (mV/
°C)
100
70
50
30
20
10
7
5
3
2
1
10
RANGE
VZ @ IZ (NOTE 2)
20
30
50
VZ, ZENER VOLTAGE (VOLTS)
70
100
Figure 4a. Range for Units to 12 Volts
Figure 4b. Range for Units 12 to 100 Volts
θV
Z , TEMPERATURE COEFFICIENT (mV/
°C)
θV
Z , TEMPERATURE COEFFICIENT (mV/
°C)
200
180
160
+6
+4
+2
20 mA
0
0.01 mA
–2
–4
3
4
1 mA
NOTE: BELOW 3 VOLTS AND ABOVE 8 VOLTS
NOTE:
CHANGES IN ZENER CURRENT DO NOT
NOTE:
AFFECT TEMPERATURE COEFFICIENTS
5
6
7
8
VZ @ IZ
TA = 25°C
140
VZ @ IZT
(NOTE 2)
120
100
120
130
140
150
160
170
180
190
200
VZ, ZENER VOLTAGE (VOLTS)
VZ, ZENER VOLTAGE (VOLTS)
Figure 4c. Range for Units 120 to 200 Volts
Figure 5. Effect of Zener Current
1000
500
0 V BIAS
200
C, CAPACITANCE (pF)
100
50
20
10
5
2
1
1
2
5
10
20
50% OF
VZ BIAS
TA = 25°C
100
70
50
C, CAPACITANCE (pF)
30
20
TA = 25°C
0 BIAS
1 V BIAS
1 VOLT BIAS
10
7
5
3
2
1
50% OF VZ BIAS
50
100
120
140
160
180
190
200
220
VZ, ZENER VOLTAGE (VOLTS)
VZ, ZENER VOLTAGE (VOLTS)
Figure 6a. Typical Capacitance 2.4–100 Volts
Figure 6b. Typical Capacitance 120–200 Volts
500 mW DO-35 Glass Data Sheet
6-4
Motorola TVS/Zener Device Data
GENERAL DATA — 500 mW DO-35 GLASS
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
10% DUTY CYCLE
5% DUTY CYCLE
Ppk , PEAK SURGE POWER (WATTS)
11 V–91 V NONREPETITIVE
1.8 V–10 V NONREPETITIVE
RECTANGULAR
WAVEFORM
TJ = 25°C PRIOR TO
INITIAL PULSE
20% DUTY CYCLE
PW, PULSE WIDTH (ms)
Figure 7a. Maximum Surge Power 1.8–91 Volts
Ppk , PEAK SURGE POWER (WATTS)
ZZ , DYNAMIC IMPEDANCE (OHMS)
1000
700
500
300
200
100
70
50
30
20
10
7
5
3
2
1
0.01
1000
500
RECTANGULAR
WAVEFORM, TJ = 25°C
200
100
50
20
10
5
2
1
0.1
1
10
100
1000
0.1
0.2
0.5
VZ = 2.7 V
47 V
27 V
TJ = 25°C
iZ(rms) = 0.1 IZ(dc)
f = 60 Hz
100–200 VOLTS NONREPETITIVE
6.2 V
1
2
5
10
20
50
100
PW, PULSE WIDTH (ms)
IZ, ZENER CURRENT (mA)
Figure 7b. Maximum Surge Power DO-204AH
100–200 Volts
Figure 8. Effect of Zener Current on
Zener Impedance
ZZ , DYNAMIC IMPEDANCE (OHMS)
1000
700
500
200
100
70
50
20
10
7
5
2
1
1
2
3
5
7
10
IZ = 1 mA
5 mA
20 mA
I F , FORWARD CURRENT (mA)
TJ = 25°C
iZ(rms) = 0.1 IZ(dc)
f = 60 Hz
1000
500
200
100
50
20
10
5 150°C
2
1
75°C
MAXIMUM
MINIMUM
25°C
0°C
20
30
50
70 100
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
VZ, ZENER VOLTAGE (VOLTS)
VF, FORWARD VOLTAGE (VOLTS)
Figure 9. Effect of Zener Voltage on Zener Impedance
Figure 10. Typical Forward Characteristics
Motorola TVS/Zener Device Data
500 mW DO-35 Glass Data Sheet
6-5
