IPC-TM-650 EN 2022 试验方法-- - 第626页
Figure 1 Current Leakage T est Circuit Configu ration AC RECEPT ACLE FOR VOL TMET ER AC RECEPT ACL E FOR UUT BNC CONNECTOR FOR VOL TMET ER TEST ELECTRODE CARD EDGE CONNECTOR 1K RESISTOR MET A L BOX DIODES G R N B L K W H …
IPC-TM-650
Number
Subject Date
Revision
Page 2 of 5
2.5.33
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
11/98
4.2
AC
millivoltmeter
capable
of
measuring
true
mvAC/rms
having
a
resolution
of
0.1
mv
AC.
The
frequency
response
of
the
millivoltmeter
shall
be
20
Hz-to-20
MhL(MilliVac
MV81
4A,
Hewlett-Packard
HP3400B,
or
equivalent).
4.3
DC
millivoltmeter
capable
of
measuring
at
least
60
mv
DC
and
having
a
resolution
of
1
mv
DC
4.4
Ohmmeter
with
a
digital
readout
unit.
It
shall
possess
scales
that
can
measure
resistances
beyond
5
MQ
with
an
accuracy
of
±
100
KQ
or
better
(±
1
0%
or
better
of
the
lower
limit).
The
ohmmeter
shall
have
a
resolution
of
0.1
MQ
or
better.
4.5
Storage
oscilloscope,
100
Mhz
bandwidth
or
faster,
1
MQ
input
vertical
amplifier
4.6
Oscilloscope
probe
-
X10
Attenuation
4.7
Constant
current
Source
capable
of
providing
10
milli¬
amps
DC
4.8
Resistor,
4.99
Q,
1
%
precision
%w
or
greater
(any
com¬
mercially
available
brand
carbon
or
metal
film)
4.9
Power
line
filter,
20
ampere
@115
VAC,
50
dB
insertion
loss
@
5
Mhz/50Q
4.10
Test
box
(see
5.1)
4.11
Screen
room/shielded
enclosure
(optional)
capable
of
accommodating
the
entire
UUT,
cord,
and
hand
piece.
A
fil¬
tered
AC
power
receptacle
shall
be
available
from
within
(see
Method
2.5.33.4).
4.12
Resistor,
1
.00
KQ,
1%
(any
commercially
available
brand
carbon
or
metal
film)
4.13
Diodes
(two),
which
shall
be
of
the
lowest
practicable
known
forward
bias
devices.
1N34
diodes
have
been
found
satisfactory
for
this
purpose.
4.14
AC
Receptacles
(two)
4.15
Line
cord
4.16
Strain
relief
4.18
Edge
card
connector
w/mounting
hardware
4.19
Metal
(bud)
box
5
Procedure
All
the
following
test
procedures
should
be
completed
to
ensure
compliance
with
ANSI/J-STD-001
:
Method
2.5.33.1
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
—
Ground
Measurements
Method
2.5.33.2
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
—
Transient
Measurements
Method
2.5.33.3
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
—
Current
Leakage
Measurements
To
construct
a
bench
top
shielded
enclosure
for
use
in
lieu
of
a
screen
room,
refer
to:
Method
2.5.33.4
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
—
Shielded
Enclosure
5.1
Test
Box
Testing
has
shown
that
for
UUTs
that
utilize
high
frequency
circuits,
layout
and
cord
positioning
can
influ¬
ence
the
AC
current
leakage
reading.
A
compact
configura¬
tion
such
as
the
one
shown
in
Figure
1
minimizes
those
influ¬
ences
(see
Method
2.5.33.3).
6
Notes
6.1
Pass/Fail
Limits
for
Transients
and
Steady-Sate
Voltage
EOS/ESD
papers
typically
discuss
possible
dam¬
age
to
electronic
components
coming
from
electrostatic
dis¬
charge
(ESD).
The
potentials
discussed
typically
are
1
00's
and
1000's
of
volts.
This
test
method
is
also
concerned
with
the
possible
damage
to
electronic
components
coming
from
elec¬
trical
overstress
(EOS).
The
EOS
potentials
of
concern
will
be
1
's
of
volts
down
to
millivolts.
This
test
method
strives
to
set
achievable
EOS
limits
for
soldering/desoldering
equipment
based
upon
the
ability
to
construct
soldering
equipment
as
well
as
resolve
small
potentials
from
background
interference.
Although
any
electronic
component
can
be
damaged
by
suf¬
ficient
amounts
of
EOS/ESD,
conventional
wisdom
states
that
semiconductors
are
the
most
susceptible.
Two
obvious
EOS/
ESD
caused
failure
modes
in
semiconductors
are:
4.17
BNC
Connector
•
Dielectric
breakdown
or
reverse
voltage
breakdown
due
to
excessive
potential
Figure 1 Current Leakage Test Circuit Configuration
AC RECEPTACLE
FOR VOLTMETER
AC RECEPTACLE
FOR UUT
BNC CONNECTOR
FOR VOLTMETER
TEST ELECTRODE
CARD EDGE
CONNECTOR
1K RESISTOR
METAL BOX
DIODES
G
R
N
B
L
K
W
H
T
TO AC
IPC-TM-650
Number
Subject Date
Revision
Page 3 of 5
IPC-2.5.33-1
2.5.33
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
11/98
•
Junction
overheated
due
to
excessive
forward
current
6.2
Limits
to
Prevent
Voltage
Breakdown
Due
to
Indi¬
vidual
Transients
As
integrated
circuit
geometries
shrink,
dielectric
breakdown
voltage
ratings
also
diminish.
One
semi¬
conductor
discussed
here
(battery
operated
integrated
cir¬
cuits)
currently
represents
the
lowest
breakdown
ratings.
S-MOS
Systems'
SMC62L35
single-chip
microcomputer
is
designed
to
run
from
a
single
1.5
volt
battery.
It
has
an
abso¬
lute
maximum
voltage
(damage
could
result)
of
2
volts.
The
recommended
limit
for
individual
transients
is
2
volts
peak.
6.3
Limits
to
Prevent
Overheating
Due
to
Steady-State
Leakage
Most
semiconductor
junctions
are
intentionally
designed,
but
in
integrated
circuits,
there
are
also
unavoidable
intrinsic
junctions.
Also,
there
are
junctions
that
are
never
sup¬
posed
to
be
operated
in
the
forward
direction
(i.e.,
JFETs
and
tuning
diodes).
The
devices
are
not
well
character-ized
by
the
manufacturer
regarding
the
maximum
forward
current.
Regardless
of
the
nature
of
the
junction,
simultaneous
forward
current
and
voltage
drop
results
in
power
dissipation.
If
the
junction
power
results
in
a
sufficient
temperature
increase,
the
junction
may
be
changed
or
destroyed.
It
is
possible
to
pre¬
vent
forward
current
from
flowing
through
a
junction
simply
by
keeping
the
applied
voltage
below
the
forward
junction
volt¬
age
rating.
Two
semiconductors
discussed
here
represent
the
lowest
forward
junction
voltage
ratings:
Schottky
diodes
and
germanium
diodes.
Motorola's
MBD201
Schottky
diode
and
most
common
germanium
diodes
begin
to
conduct
at
220
millivolts.
The
test
method
apparatus
represents
these
by
including
commonly
available
1
N34
germanium
diodes.
To
be
sure
no
junction
heating
can
be
caused
by
the
UUT,
the
cur¬
rent
should
be
zero.
But
practically,
since
zero
is
difficult
to
measure,
a
1
microamp
maximum
tolerance
can
be
permitted
without
fear
of
overheating
the
junction.
The
recommended
limit
for
current
leakage
is
1
microamp
(flowing
through
a
closed
circuit,
which
includes
parallel
head-to-tail
germanium
diodes).
Test Procedure Pass/Fail Criteria Value Recorded Status
Ground Measurements (2.5.33.1) 5 [ Pass [ Fail
Transient Measurements/Pass 1 (2.5.33.2)
2 V peak V [ Pass [ Fail
Transient Measurements/Pass 2 (2.5.33.2)
2 V peak V [ Pass [ Fail
Transient Measurements/Pass 3 (2.5.33.2)
2 V peak V [ Pass [ Fail
Current Leakage Measurements (2.5.33.3)
1.0 µ-amp DC µ-amp DC [ Pass [ Fail
Current Leakage Measurements (2.5.33.3) 1.0 µ-amp ACrms µ-amp ACrms [ Pass [ Fail
Equipment Function Brand Model Calibration Date
AC millivoltmeter true mvAC/rms
DC millivoltmeter 60 mv DC
Ohmmeter resistances beyond 5
M
Storage Oscilloscope 100 Mhz bandwidth or
faster, 1 M
input
vertical amplifier
Constant Current Source 10 milliamps DC
Equipment Scale Used Cal / Std Meas. Baseline Meas.
AC millivoltmeter
DC millivoltmeter
Ohmmeter
Storage Oscilloscope
Constant Current Source
NAME: DATE:
COMPANY: PHONE:
IPC-TM-650
Number
Subject Date
Revision
Page 4 of 5
2.5.33
Measurement
of
Electrical
Overstress
from
Soldering
Hand
Tools
11/98
6.4
Test
Results
Complete
ALL
shaded
areas.
Description
of
UUT
(brand,
model
configuration,
etc.):
Q Q
Description
of
Test
Equipment
and
Configuration
Q
Q
Additional
Comments:
Test
Completed
by: