Flex Series (Z Foil)
The Future COTS Bulk Metal
®
Foil Resistors are Already Here
The Future COTS Bulk Metal® Foil Resistors are Already Here
with Flexible Terminations System and
Load-Life Stability of 0.005% (50 ppm)
FEATURES AND BENEFITS
• Temperature coefficient of resistance (TCR):
±0.2 ppm/°C typical (–55°C to +125°C, +25°C ref.)
• Tolerance: to ±0.01%
• Power coefficient of resistance “∆R due to self heating:”
5 ppm at rated power
• Electrostatic discharge (ESD) at least to 25 kV
• Load-life stability: ±0.005% (70°C, 2000 h)
• Resistance range: 5
Ω
to 80 kΩ (for higher and lower
values, please contact us)
• Bulk Metal Foil resistors are not restricted to standard
values; we can supply specific “as required” values at
no extra cost or delivery (e.g., 1K01234 vs. 1 k)
• Power rating: to 600 mW at +70°C
• Thermal stabilization time: <1 s (within 10 ppm of
steady state value)
• Non inductive, non capacitive design
• Current noise: 0.010 μV
RMS
/V of applied voltage
(<–40 dB)
• Voltage coefficient: <0.1 ppm/V
• Low harmonic distortion, linear behavior
• Non hot spot design
• Inductive: <0.08 μH
• Terminal finishes available: lead (Pb)-free, tin/lead alloy,
or silver
Flexible terminations assure minimal stress
transference from the PCB due to a difference
in thermal coefficient of expansions (TCE).
generation of Bulk Metal
®
Foil technology, Z Foil, the
Flex Series' flexible terminations system is designed to
establish pliability while maintaining terminal strength,
solderability, stability, and electrical specifications.
The flexible terminations absorb board stresses, thereby
prevening external stresses from reaching the resistance
element.
Why choose the Flex Series
• Provides superior flex performance compared to
standard terminations systems
• Flexible terminations isolate resistor body from PCB
stresses
• Superior flex performance up to several mm
Stress checklist:
1. Where is the resistor going to be placed? Around big or
heavy components? Solution: Flex Series.
2. Are you intending to place the resistor close to the PCB
edges or corners? (Stress can occur due to bending or
CTE difference.) Solution: Flex Series.
3. Will the PCB be exposed to high levels of boards
flexure during assembly or mounting? Solution: Flex
Series.
INTRODUCTION
When mounted on a board that is bent or flexed either
during the manufacturing process or in the field,
resistors can develop cracks that affect their electrical
performances. The Flex Series is a surface-mount, multi-
featured precision resistor that incorporates a unique
flexible terminations system. Integrated with the latest
Table 1—Tolerance and TCR vs. Resistance
Value
(–55°C to +125°C, +25°C Ref.)
Value
(Ω)
50 Ω to 80 kΩ
20 Ω to <50 Ω
10 Ω to <20 Ω
5 Ω to <10 Ω
Figure 1—Power Derating Curve
200
Percent of Rated Power (%)
175
150
125
100
75
50
25
0
–75
–25
+25
+75
+125
Ambient Temperature (°C)
+175
–55 °C
+ 70 °C
Standard
Tolerance
(1)
(%)
±0.01%
±0.02%
±0.05%
±0.1%
Typical TCR and
Max. Spread
(1)
(ppm/°C)
±0.2 ±1.8
±0.2 ±2.8
±0.2 ±4.8
±0.2 ±6.8
Note
(1)
For values <5 Ω and tighter performance, contact us.
Note
* This datasheet provides information about parts that are
RoHS-compliant and/or parts that are non-RoHS-compliant.
For example, parts with lead (Pb) terminations are not RoHS
compliant. Please see the information/tables in this datasheet
for details.
Document No.: 63257
Revision: 04-Apr-2016
For any questions, contact
foil@vpgsensors.com
www.vishayfoilresistors.com
1
Flex Series (Z Foil)
Table 2—Specifications
Parameters
Resistance Range
Rated Power
Weight
Packaging
Specifications
Flex-1
5 Ω to 33 kΩ
5
Ω
to 10 kΩ
0.250 W at 70°C
0.125 W at 125°C
10 kΩ to 33 kΩ
0.160 W at 70°C
0.08 W at 125°C
Flex-2
5 Ω to 80 kΩ
5
Ω
to 30 kΩ
0.6 W at 70°C
0.3 W at 125°C
30 kΩ to 80 kΩ
0.4 W at 70°C
0.2 W at 125°C
0.1143 g
0.244 g
Bulk (loose), waffle pack or tape and reel, per EIA-481-1
Table 3—Performances
Test
Max. Working Voltage
Max. Operating Temperature
Working Temperature Range
Thermal Shock
Short Time Overload
Low Temperature Operation
Dielectric Withstanding
Voltage
Insulation Resistance
Resistance to Soldeing Heat
Moisture Resistance
Shock
Vibration, High Frequency
Conditions
Flex-1
73 V
+175°C (see Figure 1)
–55°C to +125°C (MIL range)
–65°C to +150°C; 30 min; 5 cycles
6.25 x rated power; 5 s
–65°C, 24 h (no load): 45 min at rated power
Atmospheric pressure; AC 200 V; 1 min
DC 100 V; 1 min
260°C for 10 s
+65°C to –10°C; 90% to 98% RH; rated power; 240 h
100 G; Sawtooth
10~2000~10 Hz; 20 G; X, Y, Z each 2.5 h
Flex-2
180 V
Maximum Limit
(1)
—
—
—
R > 100 Ω: ±0.02% (200 ppm)
R ≤100 Ω: ±0.03% (300 ppm)
±0.01% (100 ppm)
±0.01% (100 ppm)
±0.01% (100 ppm)
over 10 000 MΩ
±0.03% (300 ppm)
±0.03% (300 ppm)
±0.01% (100 ppm)
±0.01% (100 ppm)
Flex 1
0.005%, typical
0.02%, typical
0.05%, max
Flex 2
0.005%, typical
0.015%, typical
0.05%, max
Load Life Stability (2000 h)
0.04 W at +70°C
0.25 W at +70°C
0.125 W at +125°C
0.1 W at +70°C
0.6 W at +70°C
0.3 W at +125°C
High Temperature Exposure
175°C; no load 2000 h
±0.1% (1000 ppm)
Note
(1)
As shown +0.01
Ω
to allow for measurement errors at low values.
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Document No.: 63257
Revision: 04-Apr-2016
Flex Series (Z Foil)
Table 4—Dimensions
in Inches (Millimeters)
Side View
L
TH Minimum
VALUE (5 DIGITS)
Top View
100R0T
z
TOLERANCE
Z FOIL
INDICATOR
Stand Off
P
P
End View
H
V
(DATE CODE)
-
W
LEAD (Pb)-FREE INDICATOR
Bottom View
W
H
0.098 ±0.012
(2.49 ±0.30)
0.110 ±0.012
(2.79 ±0.30)
P
0.051 ±0.012
(1.30 ±0.30)
0.051 ±0.012
(1.30 ±0.30)
TW
TW
Model
Flex-1
Flex-2
L
0.236 ±0.012
(5.99 ±0.30)
0.287 ±0.012
(7.29 ±0.30)
TH Minimum
0.039
(0.99)
0.039
(0.99)
0.126 ±0.012
(3.20 ±0.30)
0.170 ±0.012
(4.32 ±0.30)
0.087 ±0.004
(2.21 ±0.10)
0.095 ±0.004
(2.41 ±0.10)
Table 5—Recommended Mounting Pad Geometries
in Inches (Millimeters)
Reflow Solder Pads
D
C
B
E
A
Model
Flex-1
Method
A
Min
0.110
(2.79)
0.118
(3.00)
B
Ref
0.106
(2.69)
C
Ref
0.124
(3.15)
0.175
(4.45)
D
± 0.04 (± 1.02)
0.337
(8.55)
0.388
(9.86)
E
Ref
0.050
(1.27)
Reflow
Flex-2
Figure 2—Therman Expansion
Bulk Metal
®
Foil Flex Series Resistor
Wrap Around Metal Film
Before Thermal Expansion of PCB
Before Thermal Expansion of PCB
Flexible Terminal
Chip Raised
Crack
Soldering Crack
After Thermal Expansion of PCB - T
After Thermal Expansion of PCB - T
Document No.: 63257
Revision: 04-Apr-2016
For any questions, contact
foil@vpgsensors.com
www.vishayfoilresistors.com
3
Flex Series (Z Foil)
Figure 3—Trimming to Values
(conceptual illustration)
Interloop
capacitance
reduction
in series
Mutual
inductance
reduction
due to change
in current
direction
Current path
before trimming
Current path after trimming
Figure 6—Typical TCR Curve Z Foil
+500
TCR Values for Different Temperature Ranges
+400
+300
Note
To acquire a precision resistance value, the Bulk Metal
®
Foil
chip is trimmed by selectively removing built-in “shorting bars.”
To increase the resistance in known increments, marked
areas are cut, producing progressively smaller increases in
resistance. This method reduces the effect of “hot spots” and
improves the long-term stability of Bulk Metal Foil resistors.
Trimming process
removes this material
from shorting strip area
changing current path
and increasing
resistance
Foil shown in black, etched spaces in white
+100
R
0
R
(ppm)
–100
–200
–300
–500
+200
0.05 ppm/°C
–0.1 ppm/°C
–0.16 ppm/°C
–55
–25
0.1 ppm/°C
0.14 ppm/°C
0.2 ppm/°C
+100
+125
–400
0
+25
+60 +75
Ambient Temperature (°C)
Notes
• For more details, see Table 1.
• The TCR values for <80
Ω
are influenced by the
termination composition and the result is deviation from
this curve.
Figure 5—Part Number Information
GLOBAL PART NUMBER: Y201510K0000T9R
DENOTES PRECISION
Y
VALUE
R
=
Ω
K
= kΩ
TYPE
0
= tin/lead
9
= lead (Pb)-free
1 to 999
= Custom
Y
2
0
1
5
1
0
K
0
0
0
0
T
9
R
PRODUCT CODE
2014
= Flex-1
2015
= Flex-2
RESISTANCE TOLERANCE
T
= ±0.01%
Q
= ±0.02%
A
= ±0.05%
B
= ±0.1%
C
= ±0.25%
D
= ±0.5%
F
= ±1.0%
PACKAGING
L
= Bulk pack
R
= Tape and reel
W
= Waffle pack
FOR EXAMPLE: ABOVE GLOBAL ORDER Y2015 10K0000 T 9 R:
TYPE: Flex-2
VALUE: 10.0 kΩ
ABSOLUTE TOLERANCE: ±0.01%
TERMINATION: Lead (Pb)-free
PACKAGING: Tape and reel
Flex-2
MODEL
Flex-1
Flex-2
PART DESCRIPTION: Flex-2 10K000 TCR0.2 T S T (will continue to be used)
10K000
OHMIC VALUE
10.0 kΩ
TCR0.2
TCR
CHARACTERISTIC
T
RESISTANCE
TOLERANCE
T
= ±0.01%
Q
= ±0.02%
A
= ±0.05%
B
= ±0.1%
C
= ±0.25%
D
= ±0.5%
F
= ±1.0%
S
TERMINATION
S
= Lead (Pb)-free
B
= Tin/Lead
T
PACKAGING
B
= Bulk pack
T
= Tape and reel
W
= Waffle pack
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4
For any questions, contact
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Document No.: 63257
Revision: 04-Apr-2016
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Copyright Vishay Precision Group, Inc., 2014. All rights reserved.
Document No.: 63999
Revision: 15-Jul-2014
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