VHP4Z, VPR247Z
Bulk Metal® Z- Foil Technology Ultra High Precision
Hermetically Sealed 4-Terminal Power Current Sensing Resistors with
TCR as Low as 0.05 ppm/°C and Power up to 10 Watts
FEATURES
Temperature coefficient of resistance TCR:
0.05 ppm/°C typical (0 °C to + 60 °C)
+0.2 ppm/°C typical (- 55 °C to + 125 °C,
+ 25 °C ref.)
Resistance range: 0.25to 500
Tolerance: to ± 0.01 % (see table 1)
Power rating (heat-sinked): 10 W (see table 2)
Load life stability:
± 0.005 % typical (50 ppm), 3 W on heatsink at + 25 °C,
2000 h
± 0.01 % typical (100 ppm), 3 W in free air at + 25 °C,
2000 h
± 0.01 % typical (100 ppm), 10 W on heatsink at + 25 °C,
2000 h
Vishay Foil resistors are not restricted to standard values,
we can supply specific “as required” values at no extra cost
or delivery (e.g. 1K2345 vs. 1K)
Thermal stabilization time < 1 s (nominal value achieved
within 10 ppm of steady state value)
Electrostatic discharge (ESD) at least to 25 kV
Non inductive, non capacitive design
Rise time: 1 ns effectively no ringing
Current noise: 0.010 µVRMS/V of applied voltage (< - 40 dB)
Voltage coefficient < 0.1 ppm/V
Non inductive: < 0.08 µH
Non hot spot design
Terminal finishes available:
VHP-4Z:
lead (Pb)-free or tin/lead alloy
VPR247Z:
gold plated
INTRODUCTION
Vishay Foil Resistors (VFR) Model VHP-4Z offers welded
construction and screw mounting directly to a metal heat sink
for maximum heat transfer. Hermetic sealing and nitrogen
back fill provide the maximum protection against
environmental stresses, thereby ensuring long term stability.
A special feature of this construction is Kovar eyelet’s and
solder-plated OFHC copper leads providing the lowest
thermal EMFs in the industry.
VFR Model VPR247Z has many of the advantages of the
VHP4Z but with significantly reduced size and weight. It also
has gold plated copper leads.
These series should be selected where rapid
R
stabilization
and resistance stability under transient power conditions is
required. These products achieve optimum performance
when mounted on a chassis or cooled heat sink. The Z-Foil
technology provides extremely low PCR under defined
conditions (see figure 2 and figure 3). The low absolute TCR
provided by the Z-Foil technology is measured over the
temperature range of - 55 °C to + 125 °C or 0 °C to + 60 °C,
+ 25 °C reference (see figure 7).
All of these devices utilizing the Z-Foil technology are
provided with a true 4 terminal Kelvin connection. This is a
must for precise current sensing when the resistance value
is less than 100
(see figure 4).
Custom high power designs can be developed for your
specific applications, for more information please contact us.
TABLE 1 - TOLERANCE AND TCR VS.
RESISTANCE VALUE
(- 55 °C to + 125 °C,
+ 25 °C Ref.)
RESISTANCE
RANGE ()
10 to < 500
5 to < 10
2 to < 5
1 to < 2
TIGHTEST
TOLERANCE
± 0.01 %
± 0.02 %
± 0.05 %
± 0.1 %
± 0.25 %
±0.5 %
± 0.2 ± 2.8
± 0.2 ± 1.8
TYPICAL TCR
AND MAX.
SPREAD
(ppm/°C)
FIGURE 1 - POWER DERATING CURVE
- 55 °C
+ 25 °C
100
75
50
25
0
- 50
0
+ 50
+ 100
+ 150
+ 200
RATED POWER (%)
0.5 to < 1
0.25 to < 0.5
AMBIENT TEMPERATURE
* Pb containing terminations are not RoHS compliant, exemptions may apply
Document Number: 63239
Revision: 10-Mar-15
For any questions, contact
foil@vpgsensors.com
www.vishayfoilresistors.com
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VHP4Z, VPR247Z
TABLE 2 - GENERAL SPECIFICATIONS
(4)
Power Coefficient of Resistance (PCR)
Power Rating
At + 25 °C (see Fig. 1)
Current Noise
High Frequency Operation
Rise time
Inductance (L)
(2)
Capacitance (C)
Thermal resistance
Operating Temperature Range
Hermeticity
Maximum Working Voltage
(3)
Thermal EMF
Notes
1. Heat sink chassis
MIL-PRF-39009/1:
dimensions
and
requirements
MM
152.4
101.6
50.8
1.0
per
2. Inductance (L) due mainly to the leads.
3. Maximum ambient temperature is + 150 °C.
4. Weight: VHP4Z = 15 g maximum , VPR247Z = 7 g maximum.
1.0 ns at 1 k without ringing
0.1 µH maximum; 0.08 µH typical
1.0 pF maximum; 0.5 pF typical
6 °C/W
- 55 °C to + 150 °C
10
-7
Atmospheric cc/s maximum
600 V
0.1 µV/°C maximum (lead effect)
2.5 µV/W maximum (power effect)
10 W or 3 A (whichever is lower) - heat sink
(1)
3 W or 3 A (whichever is lower) - free air
< 0.010 µV (RMS)/V of applied voltage
(- 40 dB)
4 ppm/Watt Maximum
(Mounted on a cooled heat sink held at + 25 °C)
INCHES
L
W
H
T
6.00
4.00
2.00
0.04
TABLE 3 - ENVIRONMENTAL PERFORMANCE
TEST OR CONDITION
Thermal Shock
Short Time Overload
(5 x rated power for 5 s)
Terminal Strength
High Temperature Exposure
(2000 h at + 150 °C)
Moisture Resistance
Low Temperature Storage
(24 h at - 55 °C)
Shock
(specified pulse)
Vibration
(high frequency)
Load Life
(rated power
(3)
, + 25 °C, 2000 h)
(1)
TYPICAL
R
LIMITS
0.01 %
0.01 %
0.02 %
0.02 %
0.02 %
0.005 %
0.01 %
0.01 %
0.01 %
MAXIMUM
R
LIMITS
0.02 %
0.02 %
0.05 %
0.05 %
0.05 %
0.01 %
0.02 %
0.02 %
0.02 %
Note
(1)
R’s
plus additional 0.0005
for measurement error
(2)
Maximum overload rating is 15 W (5 x rated power in free air; 1.5 x rated power on heatsink), with applied voltage not to exceed 750 V.
(3)
3W in free air or 10W on heat sink
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Document Number: 63239
Revision: 10-Mar-15
VHP4Z, VPR247Z
FIGURE 2 - RAPID STABILIZATION
RESISTANCE DEVIATION, ppm
15
10
5
0
-5
- 10
- 15
0
20
40
60
80
100
TIME, s
RESISTANCE CHANGE UNDER LOAD AT 10 WATTS
MOUNTED ON COOLED HEAT SINK HELD AT + 25 °C
120
140
160 180 200
FIGURE 3 - POWER COEFFICIENT (PCR)
RESISTANCE DEVIATION, ppm
60
40
20
0
- 20
- 40
- 60
0
5
8
APPLIED POWER, W
RESISTANCE CHANGE VS APPLIED POWER
MOUNTED ON COOLED HEAT SINK HELD AT + 25 °C
1
2
10
FIGURE 4 - KELVIN CONNECTION
I
1
r
1
R
r
2
Kelvin (4-terminal) connections are used for these low ohmic value products to
I
2
measure a precise voltage drop across the resistive element. In these
applications the contact resistance, lead resistance, and their TCR effect may
be greater than that of the element itself and could cause significant errors if
the standard 2-terminal connection is used. Figure 4 shows a high impedance
measurement system where r
5
approaches infinity and I
m
approaches zero
resulting in negligible IR drop through r
3
and r
4
which negates their lead
resistance and TCR effect. With the voltage sense leads E
1
and E
2
inside of r
1
and r
2
the resistance and TCR effect of the current leads, I
1
and I
2
are negated
and only the resistance and TCR of the element R are sensed. This method of
measurement is essential for precise current sensing.
r
3
I
m
r
4
0
r
5
∞
FIGURE 5 - VHP4Z STANDARD IMPRINTING AND DIMENSIONS
in inches (millimeters)
0.266 (6.76)
± 0.005 (± 0.13)
0.335 (8.51)
± 0.005 (± 0.13)
Standard Marking
Arrangement
Print Spec
Model Number
VFR
VHP4Z
12R500
0.1 %
BXXXX
Mounting
Hole
0.665 (16.89)
± 0.005 (± 0.13)
1.186 (30.13)
± 0.005 (± 0.13)
1.530 (38.86)
± 0.005 (± 0.13)
I1
I2
TO-3 Cap
TO-3 Base
0.040 (1.00) Dia.
± 0.005 (± 0.13)
0.770 (19.56)
Max. Dia.
0.45 (11.43)
Min.
Resistance
Value
Tolerance
Date Code
29
B1329 = 13
(Year)(Week)
0.222
(5.64)
E1
E2
0.156 Dia. (3.9)
± 0.005 (± 0.13)
0.43 (10.92)
± 0.01 (± 0.25)
1.00 (25.4)
± 0.005 (± 0.13)
I1
E1
E2
I2
Case not active; insulators not required; mounting hardware not supplied.
Document Number: 63239
Revision: 10-Mar-15
For any questions, contact
foil@vpgsensors.com
www.vishayfoilresistors.com
3
VHP4Z, VPR247Z
FIGURE 6 - VPR247Z STANDARD IMPRINTING AND DIMENSIONS
B
L
C
VFR
VPR247Z
BXXXX
0R2000 1%
0.140 ± 0.005
(Dia. Thru Hole)
W
H
0.010 Max.
Sleeve Extension
Date Code
10
B1310 = 13
(Year) (Week)
Tolerance
Resistance
Value
LL
I
1
E
1
E
2
I
2
S
LS
Gold Plated
Copper Leads
0.025 Dia.
A
DIMENSION
L
H
W
LL
LS
S
A
B
C
INCHES
0.690 ± 0.005
0.820 ± 0.005
0.215 ± 0.005
0.500 minimum
0.100 ± 0.005
0.200 ± 0.005
0.120 ± 0.005
0.040 ± 0.005
0.120 ± 0.005
MM
17.53 ± 0.13
20.83 ± 0.13
5.46 ± 0.13
12.70 minimum
2.54 ± 0.13
5.08 ± 0.13
3.05 ± 0.13
1.02 ± 0.13
3.05 ± 0.13
FIGURE 7 - TYPICAL RESISTANCE/
TEMPERATURE CURVE
+ 500
+ 400
+ 300
+ 200
+ 100
ΔR
0
R
(ppm)
- 100
- 200
- 300
- 400
- 500
0
- 55
- 25
+ 25
+ 60 + 75 + 100 + 125
Ambient Temperature (°C) and TCR Chord Slopes for
Different Temperature Ranges
- 0.16 ppm/°C
FIGURE 8 - TRIMMING TO VALUES
(Conceptual Illustration)
Interloop Capacitance
Reduction in Series
0.05 ppm/°C
- 0.1 ppm/°C
0.1 ppm/°C
0.14 ppm/°C
0.2 ppm/°C
Current Path
Before Trimming
Current Path
After Trimming
Trimming Process
Removes this Material
from Shorting Strip Area
Changing Current Path
and Increasing
Resistance
Mutual Inductance
Reduction due
to Change in
Current Direction
Note
• The TCR values for < 100
are influenced by the termination
composition and result in deviation from this curve
Note:
Foil shown in black, etched spaces in white
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Document Number: 63239
Revision: 10-Mar-15
VHP4Z, VPR247Z
TABLE 4 - GLOBAL PART NUMBER INFORMATION
NEW GLOBAL PART NUMBER: Y1480400R000T9L (preferred part number format)
DENOTES PRECISION
Y
VALUE
R
=
K
= k
AER*
0
= standard
9
= lead (Pb)-free
1 - 999
= custom
Y
1
4
8
0
4
0
0
R
0
0
0
T
9
L
PRODUCT CODE
1479
= VHP4Z
1480
= VPR247Z
RESISTANCE TOLERANCE
T
= ± 0.01 %
Q
= ± 0.02 %
A
= ± 0.05 %
B
= ± 0.1 %
C
= ± 0.25 %
D
= ± 0.5 %
PACKAGING
L
= bulk pack
FOR EXAMPLE: ABOVE GLOBAL ORDER Y1480400R000T9L:
TYPE: VPR247Z
VALUE: 400
ABSOLUTE TOLERANCE: ± 0.01 %
TERMINATION: lead (Pb)-free
PACKAGING: bulk pack
HISTORICAL PART NUMBER: VPR247ZT 400R T B (will continue to be used)
VPR247Z
MODEL
VHP4Z
VPR247Z
T
TERMINATION
T
= lead (Pb)-free
None = tin/lead alloy
400R
OHMIC VALUE
400
T
RESISTANCE
TOLERANCE
T
= ± 0.01 %
Q
= ± 0.02 %
A
= ± 0.05 %
B
= ± 0.1 %
C
= ± 0.25 %
D
= ± 0.5 %
B
PACKAGING
B
= bulk pack
Note
* For non-standard requests, please contact Application Engineering.
Document Number: 63239
Revision: 10-Mar-15
For any questions, contact
foil@vpgsensors.com
www.vishayfoilresistors.com
5
