Application Note

VISHAY GENERAL SEMICONDUCTOR
www.vishay.com
Protection Diodes
Application Note
Selecting Automotive Power Line
Polarity Protection Diodes
By Soo Man (Sweetman) Kim, Senior Application Manager
A major challenge in automotive design is protecting electronics - such as control units, sensors, and entertainment systems against damaging reverse voltages, voltage transients, electrostatic discharge (ESD), and noise that are present on the power
line. Rectifiers are ideal solutions for automotive electronic power line protection and have several important parameters for
these applications, including forward current, repetitive reverse voltage, forward surge current, and fusing rate.
PARAMETERS IN AUTOMOTIVE ELECTRONIC EQUIPMENT TEST CONDITIONS AND APPLICATIONS
Basic circuits for polarity protection are shown in Fig 1. Circuit (A) offers polarity protection only, while circuit (B) features polarity
protection with load dump suppression.
+
+
Protected
LOAD
GND
Protected
LOAD
GND
(A)
(B)
Fig. 1 - Basic Polarity Protection Circuits
Following are definitions for major parameters to consider when selecting a power line polarity protection diode for your
automotive application.
Maximum Repetitive Reverse Voltage (VRRM)
Revision: 09-Oct-12
Document Number: 89961
1
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
APPLICATION NOTE
The maximum repetitive reverse voltage is the maximum voltage that the diode can withstand in reverse bias mode. In reverse
bias mode, leakage current through the diode can generate heat in the diode junction and lead to thermal runaway. Tests that
simulate this condition include the U.S.’s ISO-7637-2 pulse 1 and 3a, and Japan’s JASO D001-94, standard type B and E. Each
peak voltage for these tests is specific in the folowing tables and figures.
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
TABLE 1: ISO-7637-2, PULSE 1
SYSTEM
(V)
Us
(V)
Ri
()
td
(ms)
tr
(μs)
12
- 75 to - 150
10
2
1
24
- 300 to - 600
50
1
3
t1
(s)
t2
(ms)
t3
(μs)
BURST CYCLE/
PULSE REPITITION
TIME
(s)
TEST
PULSES
> 0.5
200
< 100
Min. 0.5
500
V
t2
t3
UA
E1
0V
0.1 US
US
0.9 US
tr
td
t1
Fig. 2 - ISO-7637-2, Pulse 1
TABLE 2: ISO-7637-2, PULSE 3a
SYSTEM
(V)
Us
(V)
12
- 112 to - 220
24
- 150 to - 300
Ri
()
td
(ns)
tr
(ns)
t1
(μs)
t4
(ms)
t5
(ms)
BURST CYCLE/
PULSE REPITITION
TIME
(s)
TEST TIME
(h)
50
150
5
100
10
90
min. 90 to max. 100
1
V
t4
td
t5
UA
tr
0
0.1 US
APPLICATION NOTE
US
0.9 US
t1
Fig. 3 - ISO-7637-2, Pulse 3a
Revision: 09-Oct-12
Document Number: 89961
2
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
TABLE 3: JASO D001-94
CLASSIFICATION
12 V system
TYPE OF TEST
Type
24 V system
Vp
(V)
td
(μs)
B-1
- 80
60 000
B-2
- 250
2000
E
- 320
26 000
td
NUMBER OF
PULSES
f
(Hz)
Ri
()
8
100
1/30
80
100
210
100
E1
0V
36.8 % of Vp
Vp
1/f
Fig. 4 - JASO D001-94 Type B and E
According to the above test conditions, the VRRM of a diode for power line protection should be 300 V to 400 V for a 12 V power
train and 600 V for a 24 V power train.
Forward Current (IF(AV))
Average Forward Rectified Current (A)
APPLICATION NOTE
The specification for forward current in datasheets usually means the maximum average forward current the diode can handle
in the forward bias state, given the thermal limitations of the package. This parameter is related to the current usage of the circuit
in operation.
1.6
1.4
1.2
1.0
0.8
0.6
Resistive or Inductive Load
0.4
TM measured
at the Cathode Band Terminal
0.2
0
95
105
115
125 135
145
155
165
175
TM - Mount Temperature (°C)
Fig. 5 - The Maximum Forward Current Derating Curve of an AS1P on a 5 mm x 5 mm Cu Pad with a FR-4 PCB
The forward current capability varies by the temperature of the diode’s junction, as show in Fig 5. Other related parameters
include thermal resistance with the symbols RJC, RJA, RJL, and RJM.
Revision: 09-Oct-12
Document Number: 89961
3
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
Forward Surge Current (IFSM)
The specified forward surge current in a datasheet is the maximum peak current the diode can handle in the forward bias state
within specified time and pulse conditions. This rating is limited by the diode’s thermal capacity.
The forward surge current specification is related to two major operations and is simulated in the ISO-16750-2 and
JASO D001-94 automotive standards. The first operation is protecting circuitry against the high currents that occur during the
load dump condition. The second operation is simulated by ISO-7637-2 test pulse 2a and 3b, consisting of 50 ms and 100 ms
pulse widths and 2  and 50  line impedance, respectively. This is a relatively small amount of energy when compared to the
forward surge current at the load dump test condition.
Clamping voltage
+
Polarity protection
diode
Load dump
TVS
Protected
LOAD
GND
Fig. 6 - Load Dump Suppression
Load dump suppression is simulated by tests such as ISO-16750-2 test A and B, JASO standard type A and D, and others.
TABLE 4: ISO-16750-2, TEST PULSE A
PARAMETER
Usa (V)
TYPE OF SYSTEM
12 V
24 V
79 to 101
151 to 202
Ria ()
0.5 to 4
1 to 8
td (ms)
40 to 400
100 to 350
tr (ms)
10/0/-5
10/0/-5
MINIMUM TEST REQUIREMENTS
10 pulses at intervals of 1 minute
td
V
APPLICATION NOTE
tr
US
0.9 (US - UA)
0.1 (US - UA)
UA
t
0
Fig. 7 - ISO-16750-2, Test Pulse A
Revision: 09-Oct-12
Document Number: 89961
4
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
TABLE 5: ISO-16750-2, TEST PULSE B
TYPE OF SYSTEM
PARAMETER
12 V
24 V
Usa (V)
79 to 101
151 to 202
Us (V)
35
65
Ria ()
0.5 to 4
1 to 8
td (ms)
40 to 400
100 to 350
tr (ms)
10/0/-5
10/0/-5
MINIMUM TEST REQUIREMENTS
10 pulses at intervals of 1 minute
td
V
tr
US
0.9 (US - UA)
USa
0.1 (US - UA)
UA
t
0
Fig. 8 - ISO-16750-2, Test Pulse B
TABLE 6: JASO D001-94, TYPE A AND D
CLASSIFICATION
Vp
(V)
td
(μs)
A-1
70
A-2
110
D-1
110
D-2
170
TYPE OF TEST
12 V system
Type
24 V system
NUMBER OF
PULSES
f
(Hz)
Ri
()
200 000
-
0.8
1
2.5
1/30
0.4
10
400 000
-
1.5
1
2.5
1/30
0.9
10
APPLICATION NOTE
1/f
Vp
36.8 % of Vp
E1
0V
td
Fig. 9 - JASO D001-94, Type A and D
Revision: 09-Oct-12
Document Number: 89961
5
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
In this situation, high surge current is passing through the polarity protection diode, and it requires a high enough forward surge
capability to avoid failure. Estimating the surge current value in load dump suppression tests can be accomplished with the
equation:
Ipeak = ( Vpeak - VFd - Vclamping)/(Ri + Rzd)
Vpeak: Surge voltage
Vclamping: Clamping voltage
VFd: Forward voltage drop of polarity protection diode
Ri: Line impedance
Rzd: Resistance of clamping device
Fig. 10 - With the Applied Condition of 101 V Us, 12 V UB, and 1.25  Line Impedance, as Specified by ISO-16750-2 test A,
the Peak Current is 51.3 A and the Actual Clamped Current is 50.3 A.
For a detailed explanation of load dump protection, please refer to www.vishay.com/doc?88490
APPLICATION NOTE
ESD
ESD influences the operating stability and lifetime reliability of electronic modules in vehicles.
ISO-10605 and JASO standard 5.8 specify testing conditions for this parameter.
Revision: 09-Oct-12
Document Number: 89961
6
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
TABLE 7: ISO-10605: 2001 B.4.2, TEST SEVERITY LEVELS FOR ELECTRONIC MODULES
(POWER-UP TEST)
TYPE OF DISCHARGE
SEVERITY LEVEL
SELECTED LEVEL
I
II
II
IV
Direct discharge
(2)
±4
±6
±7
±8
Air discharge
(2)
±4
±8
± 14
± 15
MINIMUM NUMBER OF
DISCHARGES (1)
3
Notes
(1) Minimum delay between discharges is 5 s
(2) Values to be agreed between vehicle manufacturer and supplier
TABLE 8: JASO D001-94 AUTOMOBILE STANDARD
TEST CONDITIONS
TYPE OF TEST
Type A
Type B
Type C
TEST VOLTAGE
(kV)
A-1
± 0.5
A-2
±1
B-1
±1
B-2
±5
C-1
±5
C-2
± 10
C-3
± 15
IMPRESSING CYCLE
TIMES
NUMBER OF
IMPRESSIONS
LOCATION OF
IMPRESSIONS
Input and output terminals
1 s or more
3 times or more
Operating portion
Non-Repetitive Avalanche Energy (EAS)
This non-repetitive avalanche energy of a diode specifies the maximum energy it can absorb in the reverse bias state to protect
circuits from inductive kick back transients from motors and solenoids, or induced high reverse voltages. There is no automotive
standard for this specification.
Temperature Conditions for Automotive Electronics and Components
The JASO specifies the operating temperature range for automotive electronics as - 40 °C to + 100 °C based on their location,
such as the trunk, engine, or other places.
TABLE 9: SETTING TEMPERATURES FOR TESTING
CLASSIFICATION OF EQUIPMENT
SETTING TEMPERATURES (°C)
APPLICATION NOTE
Class 1
- 30, - 5, 25, 65, 80
Class 2
- 30, - 5, 25, 65, 80
Class 3
- 30, - 5, 25, 65, 100 (125) (1)
Class 4
As agreed between the persons concerned
Note
(1) The (125) of Class 3 is carried out according to the necessary conditions
Equipment is classified as follows:
• Class 1: Installed in the vehicle compartment and the trunk room (other than Class 4)
• Class 2: Installed outside the vehicle (other than Class 4)
• Class 3: Installed inside the engine room (other than Class 4)
• Class 4: Installed at or near the high-temperature portion or other special portion
Revision: 09-Oct-12
Document Number: 89961
7
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
VISHAY RECTIFIERS FOR POWER LINE POLARITY PROTECTION
TABLE 10: VISHAY’S HIGH CURRENT DENSITY SURFACE MOUNT ESD CAPABILITY RECTIFIERS
SERIES
VRRM (V)
MSE1P
SE10P
100 to 600
SE15P
IF (A)
IFSM (A)
1.0
20
0.925
VF (V) AT IF (A)
1.0
PACKAGE
MicroSMP
1.0
25
0.860
1.0
DO-220AA (SMP)
1.5
30
0.868
1.5
DO-220AA (SMP)
Vishay’s ESD capability rectifiers offer low forward voltage drop and meet ESD test levels as outlined in the following table.
TABLE 11: ESD IMMUNITY STANDARDS
(TA = 25 °C unless otherwise noted)
STANDARD
CLASS
VALUE
AEC-Q101-001
Human body model (contact mode)
C = 100 pF, R = 1.5 
H3B
> 8 kV
AEC-Q101-002
Machine model (contact mode)
C = 200 pF, R = 0 
M4
> 400 kV
JESD22-A114
Human body model (contact mode)
C = 150 pF, R = 1.5 
JESD22-A114
Machine model (contact mode)
C = 200 pF, R = 0 
Human body model (contact mode)
C = 150 pF, R = 150 
4
> 8 kV
Human body model (air -discharge mode) (1)
C = 150 pF, R = 150 
4
> 15 kV
IEC 61000-4-2 (2)
TEST TYPE
TEST CONDITIONS
SYMBOL
VC
3B
> 8 kV
C
> 400 kV
Notes
(1) Immunity to IEC 61000-4-2 air discharge mode has a typical performance > 30 kV
(2) System ESD standard
Vishay’s avalanche rectifiers offer the low forward voltage drop of common rectifiers, while providing the avalanche capability
to protect circuits from induced transient voltages through the power line, inductive kick back transient voltage from motors and
solenoids, and induced transient voltages from outside the power line.
TABLE 12: VISHAY’S SURFACE MOUNT AVALANCHE RECTIFIERS
APPLICATION NOTE
SERIES
VRRM (V)
IF (A)
IFSM (A)
VF (V) AT IF (A)
EAS (mJ)
PACKAGE
AS1P
200 to 1000
1.5
30
0.89
1.5
20
DO-220A
BYG10
200 to 1600
1.5
30
1.15
1.5
20
DO-214AC (SMA)
AS3BJ
600
3.0
90
0.88
3.0
30
DO-214AA (SMB)
AS3P
200 to 1000
3.0
70
0.90
3.0
30
TO-277A
AS4P
200 to 1000
4.0
100
0.92
4.0
30
TO-277A
Avalanche rectifiers are designed to protect against avalanche breakdown, which is caused by ionization created by
electron-hole pairs. This is different than Zener breakdown, which results from quantum mechanical tunneling of carriers
through the band-gap in highly doped p-n junctions.
Revision: 09-Oct-12
Document Number: 89961
8
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Application Note
www.vishay.com
Vishay General Semiconductor
Selecting Automotive Power Line Polarity Protection Diodes
References
Fulup, W. “Calculation of Avalanche Breakdown of Silicon P-N junctions.” Solid-State Electronics 10.1 (1967): 39-43. Print.
Hart, Daniel W. Introduction to Power Electronics. Taiwan: Prentice Hall/Pearson Education, 2002. Print.
Horowitz, Paul, and Winfield Hill. The Art of Electronics. Cambridge: Cambridge University Press, 1980. Print.
IEC 61000-4-2: 1995: Electromagnetic compatibility (EMC) - Part 4: Testing and measurement techniques; Section 2:
Electrostatic discharge immunity test
ISO-10605: 2001: Road vehicles - Test methods for electrical disturbances from electrostatic discharge
ISO-16750-2: 2010: Road vehicles - Environmental conditions and testing for electrical and electronic equipment
ISO-7637-2: 2010: Road vehicles - Electrical disturbance by conduction and coupling – Part 2: Electrical transient conduction
along supply lines only
JASO D001-94: Japanese automobile standard - General rules of environmental testing methods for automotive electronic
equipment
APPLICATION NOTE
IEC 61000-4-2: 1995 Electromagnetic compatibility (EMC) - Part 4: Testing and measurement techniques - Section 2:
Electrostatic discharge immunity tes
Revision: 09-Oct-12
Document Number: 89961
9
For technical questions within your region: [email protected], [email protected], [email protected]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000