SCAR (Charcroft Audio Resistor)
Charcroft Foil Resistors
Ultra High Precision, High Resolution Z-Foil Wrap Around Surface Mount
Audio Resistor, with TCR of
± 0.2 ppm/°C,Tolerance
to
± 0.01 %
and Noise
< -40 dB
F E AT U R E S
•
Temperature coefficient of resistance (TCR):
- 55°C to + 125°C, 25°C ref.
± 0.2 ppm/°C typical (see table 1)
Rated power: to 0.75 W at + 70°C
Tolerance: to ± 0.01 %
Load life stability: to ± 0.01 % at 70°C, 2000 h at rated power
Resistance range: 10Ω to 125kΩ (for higher or lower values
please contact us)
Electrostatic discharge (ESD) above 25000V
Non inductive, non capacitive design
Rise time: 1ns without ringing
Current noise: < -40 dB
Thermal EMF: 0.05 µV/°C typical
Voltage coefficient: < 0.1 ppm/V
Low inductance: < 0.08 µH typical
Non hot spot design
Terminal Finishes Available: RoHS Compliant
Tin/Lead Alloy
High precision amplifiers
High-end speaker system
High-end audio circuit
Transducer
High fidelity audio amplifier
TABLE 2 - SPECIFICATIONS
CHIP
SIZE
0805
1206
1506
2010
2512
RATED
POWER (mW)
at +70°C
200
300
300
500
750
MAXIMUM
VOLTAGE
RATING
(≤ PxR)
49V
95V
110V
200V
220V
RESISTANCE
RANGE
(Ω)
10 to 8K
10 to 25K
10 to 30K
10 to 70K
10 to 125K
•
•
•
•
•
•
•
•
•
•
•
•
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Any value at any tolerance available within resistance range
INTRODUCTION
The
SCAR,
composed of Vishay's Bulk Metal
®
Z-Foil technology,
offers all the features of the leaded CAR, but in a surface mount
version with wrap around terminations.
Whilst the regular foil resistors are already widely acknowledged as
the leading resistors for audio applications, the extremely low TCR,
improved low load life stability and power coefficient of the Z-Foil
technology makes it unrivalled for applications requiring low noise
and distortion-free properties.
Please contact our application engineering department for any non-
standard requirements.
TABLE 1 - TOLERANCE AND TCR VS RESISTANCE VALUE
(- 55 °C to + 125 °C, + 25 °C Ref.)
RESISTANCE
VALUE
(Ω)
250 to 125K
100 to < 250
50 to < 100
25 to < 50
10 to < 25
TOLERANCE
(%)
± 0.01
± 0.02
± 0.05
± 0.1
± 0.25
TYPICAL TCR & MAX.
SPREAD
(ppm/°C)
±
±
±
±
±
0.2
0.2
0.2
0.2
0.2
±
±
±
±
±
1.8
1.8
2.8
3.8
3.8
A P P L I C AT I O N S
•
•
•
•
•
FIGURE 1 - TYPICAL TCR CURVE Z-FOIL
FIGURE 2 -TRIMMING TO VALUES
(
CONCEPTUAL ILLUSTRATION)
NOTE:
Foil shown in BLACK, etched spaces in white.
Interloop Capacitance
Reduction in Series
Current Path
Before Trimming
Note:
The TCR for
values <100Ω are
influenced by the
termination composition
and result in deviation
from this curve.
Mutual Inductance
Reduction due
to Opposing
Current in
Adjacent Lines
Current Path
After Trimming
Trimming Process
Removes this Material
from Shorting Strip
Area Changing
Current Path and
Increasing
Resistance
www.charcroft.com
Document No:
ACC101
Issue:
2
Page:
1
Date:
04/09
SCAR (Charcroft Audio Resistor)
Charcroft Foil Resistors
Ultra High Precision, High Resolution Z-Foil Wrap Around Surface Mount Audio Resistor,
with TCR of
± 0.2 ppm/°C,Tolerance
to
± 0.01 %
and Noise
< -40 dB
TABLE 3 - DIMENSIONS AND LAND PATTERN in millimeters
CHIP
SIZE
0805
1206
1506
2010
2512
L
± 0.13
2.03
3.20
3.81
5.03
6.32
W
± 0.13
1.27
1.57
1.57
2.46
3.22
THICKNESS
MAXIMUM
0.64
0.64
0.64
0.64
0.64
D
± 0.13
0.38
0.50
0.50
0.64
0.81
Z***
MAXIMUM
3.10
4.40
5.05
6.27
7.40
G***
MINIMUM
0.70
1.50
2.10
2.92
3.80
X***
MAXIMUM
1.27
1.80
1.80
2.63
3.22
***Land Pattern Dimensions are per IPC-782
FIGURE 3 -POWER DERATING CURVE
FIGURE 4 - RECOMMENDED MOUNTING
A low profile solder fillet is
recommended to avoid unnecessary
stresses along top edge of
metallization. IR and vapor phase
reflow are best. Avoid the use of
cleaning agents which could attack
epoxy resins, which form part of the
resistor construction.
25% to 85% of T
TA B L E 4 - O R D E R I N G I N F O R M AT I O N
Specify SCAR (Charcroft audio resistors) as follows:
Example:
SCAR
MODEL NO.
0805
CHIP SIZE
T = RoHS compliant
None = Tin/Lead alloy
TERMINATION
250R00
RESISTANCE VALUE
T = ± 0.01%
Q = ± 0.02%
A = ± 0.05%
B = ± 0.1%
C = ± 0.25%
D = ± 0.5%
F = ± 1.0%
TOLERANCE
Resistance Value, in ohms, is expressed by a series of 6 characters, 5 of which represent significant digits while the 6th is
a dual purpose letter that designates both the multiplier and the location of the comma or decimal.
RESISTANCE
RANGE
10Ω to <1KΩ
1KΩ to 100KΩ
LETTER
DESIGNATOR
R
K
MULTIPLIER
FACTOR
x1
x 10
3
TR = Tape & Reel
None = Waffle Pack
PACKAGING
EXAMPLE
100R01 = 100.01Ω
5K2310 = 5,231Ω
For example: SCAR 0805 T 250R00Q -
Model:
SCAR 0805 Version,
Termination:
RoHS compliant;
Value:
250Ω,
Tolerance:
0.02 %
Packaging:
Waffle Pack
www.charcroft.com
Document No:
ACC101
Issue:
2
Page:
2
Date:
04/09
