KN352-0113B-0R033 Vitrohm, KN352-0113B-0R033 Datasheet - Page 8

• Manufacturer Part Number: KN352-0113B-0R033
• Manufacturer: Vitrohm

Specifications of KN352-0113B-0R033

• Resistance Value: 33 mOhm
• Power Rating: 1.5 W
• Tolerance: 3 %

General:
VITROHM offers a range of low-ohm resistors for
current sensing applications, resistance ranges
typically from 1 milliohm to 100 milliohms.
These devices are of non-wound construction and
made from flat resistive alloy wire.
The resistor‘s specification depends on the material
and the choosen dimensions, namely specific-resi-
stance, thermal conductivity and temperature
coefficient are of importance.
1. Standard, leaded types, KN-family
The „KN-resistors“ are available in standardized sizes
with choices of open-frame and ceramic cased types.
Copper leads are welded to the resistive element for
board assembly.
Attention should be given to the following:
- resistance value
- temperature coefficient
Design Notes for Current Sense Resistors
24
The value is specified over a given „measuring
length“. Between the two measuring points lies the
element plus some copper-wire for contact
purposes.
If the actual used total length of the resistor in the
application differs from this specified length, the
influence of the copper wire of 0.4 mΩ per
centimeter must be considered.
Typically the temperature coefficient of the resistive
element ranges around 150 ppm/
for details). However, the copper wire is part of the
effective resistance and influences the TC between
the contacts.
Types KN 350 ... KN 354
o
C (ask factory
- power and current rating
2. Semi-customized types, LPS-family
VITROHM provides tools to produce U-shaped low-
ohm resistors for direct board mounting.
The solder-tags (1 or 2 per side) are of given
dimensions, the size of the final unit is designed in
accordance with the applicational requirements.
If the demand for a shunt-resistor justifies a
customized solution, the LPS-family offers a variety
of possibilities.
The lower the resistance value, the more influence
of the copper leads, the higher the TC!
If the TC is of concern in a given application, a
vertical style of the KN-family should be used (type
35X-009). In this case the influence of the copper
wire is almost eliminated.
The „KN-resistors“ are standard products with a
fixed given power rating (P
rating can be of concern, especially if overload or
pulse conditions can occure.
The current limit is defined by the current density,
and 100 A per mm
maximum in power electronics. With a 0,8 mm
diameter copper wire, the current limit is 50 A.
With respect to reliability, the welding junction
between copper and resistive alloy should not carry
more than 20 A continuously.
The 50 A limit may not be exceeded even under
pulse conditions.
Types LPS 355 ... LPS 359
Marking
2
M
are considered absolute
Measuring point
70
). Nevertheless, current