Precision Resistor Type PBH

Spec Sheet R371-1/2 July 97

Technical Data

Resistance range

2 mOhm - 100 Ohm

Tolerances

1 %, 5 %

Temperature coefficient ( R > 20 mOhm )

< 50 ppm/K ( 20 °C to 60 °C )

Applicable temperature range

-55 °C to +125 °C

Load capacity

3 W / 10 W with heatsink provided

Thermal resistance to aluminum base plate

Rth < 4 K/W

Thermal resistance to ambiente

Rth < 20 K/W

Dielectric withstanding voltage

500 V AC

Inductance ( R = 100 mOhm )

< 20 nH

Stability ( nominal load at 70 °C )

deviation < 0.5 % after 2,000 h

The Resistor type PBH, which is very similar to type

TO 247 for high power transistors, features small

dimensions complemented with high load capacity and

compatibility with active components.

The use of the precision resistance material MANGANIN

as well as optimization of conductor leads and resistance

structure result in a low temperature coefficient, a long-

term stability and low inductance.

The resistor is mounted through a center bore to the

heatsink, whereby the large area of the base plate will

function as an optimum heat transfer.The thermal resistance

between resistor layer and aluminum base plate is rated

below 4 K/W, so that the temperature of the resistor foil

Remarks:

- Standard resistance values according to E12 with the additionel values of 2 and 5

- Minimum quantity of other values on request

- Tolerance 0.5% for values of 10 mOhm up

will rise only little at a nominal load of 10 W, compared with

customary resistors. This again results that the absolute

resistance deviation caused by the temperature coefficient,

is very low under load and will serve for a good stability on

overloading.

The resistor is ideally suited for applications in power

electronic and control technique, as most applications at

inductive loading will require operation with switched power

regulating units.

Short connection distances and small dimensions with

high loading capacity and low inductance are a prerequisite

for obtaining high switching frequencies.

Change of the R(T)-curve to the TCR of copper terminals

for very low ohmic 2-terminal-resistors

dimensions

( mm )

20

40

60

80

100

120

-2

-1

1

2

dR/R [%]

>200 m

Ω

100 m

Ω

20 m

Ω

10 m

Ω

5 m

Ω

-40

-20

-40

-20

20

40

60

80

100

120

-0.4

-0.2

0.2

∆R/R

0

20

40

60

80

100

120

T

0.25

0.5

0.75

1

P / P

Nenn

power derating curve

Temperature dependence of the electrical resistance

of ISA-PLAN Resistors