Current Sense Resistors:Type CD0 pages

Type CD Low Resistance Precision Chip Resistors
Page 1 of 2

Low Resistance Chip down to 0.010Ω at ±1% with unique Pedestal Terminal Design
for Current Sense in Hybrid and SMT Applications

Type CD Low Resistance Precision Chip Resistors utilize the proven Caddock
Micronox® resistance films to achieve the unique low resistance range in this
family. The special performance features of the Type CD Low Resistance
Precision Film Resistor include:
•

•
•

•
•
•

Style FC - Flip Chip version for surface mount applications.
Style WB - Wire Bond version for hybrid applications with metallized t
back surface for solder down heat sinking of the chip, includes bondable
termination pedestals to receive aluminum wire bonds.
Resistance as low as 0.010 ohm at ±1%.
Pedestal terminals in this design provide an ultra low resistance tt
connection pad which maintains the precision 0.010Ω ±1% at the point
of customer Kelvin connection to the resistor chip. The pedestal terminal t
with its copper core also provides heat spreading which enhances the t
high power handling capability.
Thermal resistance is provided to optimize high power designs when t
utilizing higher thermal conductivity circuit board substrates such as IMS t
or Alumina.
High pulse handling and overload capability.
Low inductance provides excellent high frequency and pulse response.

Style FC - Flip Chip Version
Resistance
Model

is a surface mount version with solderable pedestal terminals for flip chip soldering.
Power Capability Information

General Applications High Power Applications
Thermal Resistance - RθJC
Power Rating
Film (J) to Solder Pad (C)
at 70° C
(see note 2)
(see note 1)

Max. Chip
Temperature

Min.

Max.

CD2015FC

0.010 Ω

0.20 Ω

1.0 Watt

12.0°C/Watt

150°C

CD2520FC

0.010 Ω

0.20 Ω

1.5 Watts

9.0°C/Watt

150°C

Dimensions in inches and (millimeters)
A

.200 ±.012
(5.08 ±.30
.250 ±.012
(6.35 ±.30)

B

.150 ±.012
(3.81 ±.30)
.200 ±.012
(5.08 ±.30)

C

.063 ±.006
(1.60 ±.15)
.063 ±.006
(1.60 ±.15

Comments
D

.062 min.
(1.57 min.)
.078 min.
(1.98 min.)

Solderable Pedestal
Solderable Pedestal

Style FC Derating Curve For General Applications
RATED LOAD, %

100
80
60
40
20
0

25
70
100
150
AMBIENT TEMPERATURE, o C

Note 1: General Applications - The power rating for
general applications is based upon 0.5 sq. in. (300
mm2) of termination pad or trace area (2 oz. copper)
connected to each end of the resistor. Maximum chip
temperature is 150°C. Use Derating Curve to derate
appropriately for the maximum ambient temperature
and for the temperature limitations of the adjacent
materials.

Note 2: Thermal Resistance - In High Power Applications where the circuit board material
provides high heat sinking benefits (such as IMS, Alumina, or other) the thermal resistance of
the chip resistor is useful to establish the maximum power capability of the chip resistor in the
application. The film temperature is measured at the center of the resistor element and solder
pad temperature at the center of the solderable pedestal (point X in the recommended circuit
layout shown below). Maximum temperature of the chip resistor (at the center of chip) should
not exceed 150°C through the temperature range of the application.

Recommended Circuit Board Layout
(current and sense connections):
Fig. 1A: Recommended Kelvin layout.
C = Current connection
S = Sense connection

Applications Engineering
17271 North Umpqua Hwy.
Roseburg, Oregon 97470-9422
Phone: (541) 496-0700
Fax: (541) 496-0408
© 2003-2007 Caddock Electronics, Inc.

C

C

X

CD2015FC Standard Resistance Values:
Tolerance CD2015FC ±1% Standard.
0.010 Ω
0.015 Ω
0.020 Ω
0.025 Ω

0.030 Ω
0.033 Ω
0.040 Ω
0.050 Ω

0.075 Ω
0.10 Ω
0.20 Ω

CD2520FC Standard Resistance Values:
Tolerance CD2520FC ±1% Standard.
0.010 Ω
0.015 Ω
0.020 Ω
0.025 Ω

0.030 Ω
0.033 Ω
0.040 Ω
0.050 Ω

0.075 Ω
0.10 Ω
0.20 Ω

Custom resistance values and non-standard tolerances
can be manufactured for high quantity applications.
Please contact Caddock Applications Engineering.

Note: Actual width of current trace is based on
magnitude of current. Point of connection should
be in the area shown.

X
S

S

ELECTRONICS, INC.

e-mail: caddock@caddock.com • web: www.caddock.com
For Caddock Distributors listed by country see caddock.com/contact/dist.html

Sales and Corporate Office
1717 Chicago Avenue
Riverside, California 92507-2364
Phone: (951) 788-1700
Fax: (951) 369-1151
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