VFD244Z (Z-Foil)
Vishay Foil Resistors
Bulk Metal
®
Foil Technology Ultra High Precision Z-Foil Voltage Divider
Resistors with TCR Tracking to 0.1 ppm/°C, Power Coefficient Tracking
of 5 ppm at Rated Power, and Tolerance Match to 0.005 % (50 ppm)
D
(D 244
.C
Z
.)
VF
VF
FEATURES
R
Temperature coefficient of resistance (TCR):
absolute: ± 0.05 ppm/°C typical (0 °C to + 60 °C)
± 0.2 ppm/°C typical (- 55 °C to + 125 °C,
+ 25 °C ref.)
TCR tracking: 0.1 ppm/°C typical
Tolerance: absolute and matching to 0.005 % (50 ppm)
Resistance range: 1
to 100 k per resistive element
Power coefficient tracking “R due to self heating”: 5 ppm
at rated power
Vishay Foil resistors are not restricted to standard
values/ratios; specific “as requested” values/ratios can be
supplied at no extra cost or delivery (e.g. 1K2345 vs. 1K)
Power rating: up to 1 W at 70 °C, for the entire package,
divided proportionally between the two values
Load life ratio stability: < 0.005 % (50 ppm) 1 W at 70 °C
for 2000 h
Maximum working voltage: 350 V
Electrostatic discharge (ESD) up to 25 000 V
Non-inductive, non-capacitive design
Rise time: 1 ns effectively no ringing
APPLICATIONS
Instrumentation amplifiers
Bridge networks
Differential amplifiers
V
in
Military
Space
Medical
Automatic test equipment
Down-hole (high temperature)
R
2
R
1
-
+
V
out
VFD244
VFD244Z
Current noise: 0.010 µV
RMS
/V of applied voltage (< - 40 dB)
Thermal EMF: 0.05 µV/°C typical
Voltage coefficient: < 0.1 ppm/V
Non-inductive: < 0.08 µH
Non hot spot design
Thermal stabilization time < 1 s (nominal value achieved
within 10 ppm of steady state value)
Terminal finish: lead (Pb)-free or tin/lead alloy
Compliant to RoHS directive 2002/95/EC
Prototype quantities available in just 5 working days
or sooner. For more information, please contact
foil@vishaypg.com
For better performances please contact us
TABLE 1 - RATED POWER PER ELEMENT
RESISTANCE
ELEMENT
VALUE
1
to < 100 k
MAXIMUM POWER
RATING AT 70 °C
PER ENTIRE
PACKAGE
1W
(not exceed 0.6 W
per element)
MAXIMUM POWER
RATING AT 125 °C
PER ENTIRE
PACKAGE
0.5 W
(not exceed 0.3 W
per element)
TABLE 2 - MODEL VFD244Z SPECIFICATIONS
MODEL
RESISTANCE
VALUES
500
to 100 k
100
to 500
VFD244Z
50
to 100
25
to 50
10
to 25
5
to 10
ABSOLUTE TCR
(- 55 °C to + 125 °C, + 25 °C ref.)
TYPICAL AND MAX. SPREAD
± 0.2 ppm/°C ± 1.8 ppm/°C
± 0.2 ppm/°C ± 2.3 ppm/°C
± 0.2 ppm/°C ± 2.8 ppm/°C
± 0.2 ppm/°C ± 3.3 ppm/°C
± 0.2 ppm/°C ± 3.8 ppm/°C
TOLERANCE
ABSOLUTE
± 0.005 %
± 0.005 %
± 0.01 %
± 0.01 %
± 0.02 %
± 0.05 %
MATCH
0.005 %
0.01 %
0.02 %
0.02 %
0.04 %
0.05 %
TCR TRACKING (MAX.)
SAME VALUES
0.5 ppm/°C
1.0 ppm/°C
1.5 ppm/°C
2.0 ppm/°C
2.5 ppm/°C
3.0 ppm/°C
DIFFERENT VALUES
1.5 ppm/°C
2.0 ppm/°C
2.5 ppm/°C
3.0 ppm/°C
3.5 ppm/°C
4.0 ppm/°C
* Pb containing terminations are not RoHS compliant, exemptions may apply
Document Number: 63176
Revision: 15-Dec-11
For any questions, contact:
foil@vishaypg.com
www.vishayfoilresistors.com
1
VFD244Z (Z-Foil)
Vishay Foil Resistors
INTRODUCTION
The VFD244Z voltage divider is based on the latest
generation of Bulk Metal Z-Foil technology which is the most
recommended solution for ultra high precision, stability and
reliable voltage division.
The four fundamental factors determining how “ideal” a
precision divider and network will be:
1. Initial resistance matching - or how closely the absolute
resistance value of same value resistors can be matched.
2. Initial ratio matching - or how accurately a specified ratio
between resistors of different values will be ( a corollary of
how precisely the value of individual resistors can be
controlled).
3. Tracking in operation - or how precisely the initial ratios
are maintained under a wide range of operating
conditions (temperature, humidity, load, etc.)
4. Fast response without ringing - or ability of the divider,
network to react to rapid switching without blocking the
circuit. This depends on the inductance and capacitance
of the network, as well as of the individual resistors in the
network.
VFR VFD244Z with the Z-Foil technology is designed and
manufactured to eliminate the inter-parameter compromise
inherent in all other types of precision resistors. All important
characteristics - tolerance, long term shelf life and load
stability, temperature coefficient, noise, capacitance and
inductance - are optimum, approaching in total performances
the theoretical ideal, straight wire.
The VFD244Z maintain all its design, physical and electrical
characteristics. These factors are both measurable and
predictable before, during and after manufacture.
Why is the absolute TCR of each resistors is more
important the initial TCR tracking?
Depending on technology differences, some resistors may
increase in value with an increase in temperature (+TCR)
while others will decrease in value with an increase in
temperature (-TCR), or, they may not change in value at the
same rate. Other temperature effects, such as self heating
due to the application of power can add to the ambient
temperature effects. An example of these effects can be
seen with two resistors with different TCR characteristics are
used around an operation amplifier. The amplification ratio
will be affected by the differential TCR of the resistors and
will be compounded by the self heating effects of the I
2
R
differences of the feedback vs. the sense resistor.
Good design practice would be to use fundamentally low
TCR networks in this application since this would minimize
both varying temperature and self heating effects.
This could not be accomplished with high TCR resistors,
even with good tracking.
Our application engineering department is available to
advise and make recommendations. For non-standard
technical requirements and special applications. Please
contact us.
FIGURE 1 - TRIMMING TO VALUES
(conceptual illustration)
Interloop
Capacitance
Reduction
in Series
Mutual
Inductance
Reduction due
to Opposing
Current in
Adjacent Lines
Current Path
Before Trimming
Current Path
After Trimming
Trimming Process
Removes this Material
from Shorting Strip Area
Changing Current Path
and Increasing Resistance
Note:
Foil shown in black, etched spaces in white
www.vishayfoilresistors.com
2
For any questions, contact:
foil@vishaypg.com
Document Number: 63176
Revision: 15-Dec-11
VFD244Z (Z-Foil)
Vishay Foil Resistors
FIGURE 2 - STANDARD PRINTING AND DIMENSIONS
in millimeters (inches)
Model VFD244Z and Schematic
(2)
8.9
(0.350)
VFR
VFD244Z
(D.C.)
0.3
(0.012)
19.05 Min.
(1)
(0.75 Min.)
3.5
(0.138)
Match
Tolerance
(R
2
)
(Tol.)
(R
1
)
10.5
(0.413)
R
1
R
2
1
Low
Resistance
Value
Indicator
1
2
3
1
2
3
Ø 0.6
(0.024)
3
2
1
Dimensional Tolerance: ± 0.2 (0.008)
2.54 (0.100)
(1)
(2)
Lead wires: #22 AWG solder coated copper,
Each resistor contains 2 chips of two resistive elements
FIGURE 3 - POWER DERATING CURVE
VFD244Z
Percent of Rated Power at + 70 °C
100 %
FIGURE 4 - TYPICAL RESISTANCE/
TEMPERATURE CURVE
(for more details see table 2)
TCR Chord Slopes for Different Temperature Ranges
+ 500
- 55 °C
+ 70 °C
Rated Power
75 %
+ 400
+ 300
+ 200
50 %
Recommended
operation for
< 150 ppm
ΔR
after 2000 h
load life
+ 100
ΔR
0
R
(ppm)
- 100
- 200
- 300
- 400
- 500
- 0.16 ppm/°C
- 55
- 25
0
0.05 ppm/°C
- 0.1 ppm/°C
0.1 ppm/°C
0.14 ppm/°C
0.2 ppm/°C
+ 25
+ 60 + 75
+ 100 + 125
25 %
0
- 75 - 50 - 25
0
+ 25 + 50 + 75 + 100 + 125 + 150 + 175 + 200
Ambient Temperature (°C)
Note:
• Power is divided proportionally between the 2 values (see table 1)
Ambient Temperature (°C)
Document Number: 63176
Revision: 15-Dec-11
For any questions, contact:
foil@vishaypg.com
www.vishayfoilresistors.com
3
VFD244Z (Z-Foil)
Vishay Foil Resistors
TABLE 3 - GLOBAL PART NUMBER INFORMATION
(1)
NEW GLOBAL PART NUMBER: Y0115V0058QT9L (preferred part number format)
DENOTES PRECISION
Y
VCODE
RESISTANCE
VALUE CODE
TOLERANCE MATCH
V
= 0.005 %
T
= 0.01 %
Q
= 0.02 %
A
= 0.05 %
B
= 0.1 %
D
= 0.5 %
F
= 1.0 %
PACKAGING
L
= bulk pack
Y
0
1
1
5
V
0
0
5
8
Q
T
9
L
PRODUCT CODE
0115
= VFD244Z
RESISTANCE TOLERANCE
V
= ± 0.005 %
T
= ± 0.01 %
Q
= ± 0.02 %
A
= ± 0.05 %
B
= ± 0.1 %
D
= ± 0.5 %
F
= ± 1.0 %
CHARACTERISTICS
0
= standard
9
= lead (Pb)-free
1 to 999
= custom
FOR EXAMPLE: ABOVE GLOBAL ORDER Y0115 V0058 Q T 9 L:
TYPE: VFD244Z
VALUES: 2K/20K
ABSOLUTE TOLERANCE: ± 0.02 %
TOLERANCE MATCH: 0.01 %
TERMINATION: lead (Pb)-free
PACKAGING: bulk pack
HISTORICAL PART NUMBER: VFD244ZT 2K/20K TCR0.2 Q T B (will continue to be used)
VFD244Z
MODEL
VFD244Z
T
TERMINATION
T
= lead (Pb)-free
None
= tin/lead alloy
2K/20K
OHMIC VALUE
R
1
= 2 k
R
2
= 20 k
TCR0.2
TCR
CHARACTERISTIC
Q
ABSOLUTE
TOLERANCE
V
T
Q
A
B
D
F
= ± 0.005 %
= ± 0.01 %
= ± 0.02 %
= ± 0.05 %
= ± 0.1 %
= ± 0.5 %
= ± 1.0 %
T
TOLERANCE
MATCH
V
= 0.005 %
T
= 0.01 %
Q
= 0.02 %
A
= 0.05 %
B
= 0.1 %
D
= 0.5 %
F
= 1.0 %
B
PACKAGING
B
= bulk pack
Note
(1)
For non-standard requests, please contact application engineering
www.vishayfoilresistors.com
4
For any questions, contact:
foil@vishaypg.com
Document Number: 63176
Revision: 15-Dec-11
Legal Disclaimer Notice
Vishay Precision Group
Disclaimer
ALL PRODUCTS, PRODUCT SPECIFICATIONS AND DATA ARE SUBJECT TO CHANGE WITHOUT NOTICE.
Vishay Precision Group, Inc., its affiliates, agents, and employees, and all persons acting on its or their
behalf (collectively, “Vishay Precision Group”), disclaim any and all liability for any errors, inaccuracies or
incompleteness contained herein or in any other disclosure relating to any product.
The product specifications do not expand or otherwise modify Vishay Precision Group’s terms and conditions of
purchase, including but not limited to, the warranty expressed therein.
Vishay Precision Group makes no warranty, representation or guarantee other than as set forth in the terms
and conditions of purchase.
To the maximum extent permitted by applicable law, Vishay Precision Group
disclaims (i) any and all liability arising out of the application or use of any product, (ii) any and all liability,
including without limitation special, consequential or incidental damages, and (iii) any and all implied
warranties, including warranties of fitness for particular purpose, non-infringement and merchantability.
Information provided in datasheets and/or specifications may vary from actual results in different applications
and performance may vary over time. Statements regarding the suitability of products for certain types of
applications are based on Vishay Precision Group’s knowledge of typical requirements that are often placed on
Vishay Precision Group products. It is the customer’s responsibility to validate that a particular product with the
properties described in the product specification is suitable for use in a particular application.
No license, express, implied, or otherwise, to any intellectual property rights is granted by this document, or by
any conduct of Vishay Precision Group.
The products shown herein are not designed for use in life-saving or life-sustaining applications unless otherwise
expressly indicated. Customers using or selling Vishay Precision Group products not expressly indicated for use
in such applications do so entirely at their own risk and agree to fully indemnify Vishay Precision Group for any
damages arising or resulting from such use or sale. Please contact authorized Vishay Precision Group personnel
to obtain written terms and conditions regarding products designed for such applications.
Product names and markings noted herein may be trademarks of their respective owners.
Document No.: 63999
Revision: 27-Apr-11
www.vishaypg.com
1
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
