MOUNTING

Due to their rectangular shapes and small tolerances, Surface Mountable Resistors are suitable for

handling by automatic placement systems.

Chip placement can be on ceramic substrates and printed-circuit boards (PCBs).

Electrical connection to the circuit is by individual soldering condition.

The end terminations guarantee a reliable contact.

SOLDERING CONDITION

The robust construction of chip resistors allows them to be completely immersed in a solder bath of 260qC

for 10 seconds. Therefore, it is possible to mount Surface Mount Resistors on one side of a PCB and other

discrete components on the reverse (mixed PCBs).

Surface Mount Resistors are tested for solderability at 235qC during 2 seconds within lead-free solder bath.

The test condition for no leaching is 260qC for 30 seconds. Typical examples of soldering profile and

condition that provide reliable joints without any damage are given in Fig 3. and Table 1.

Fig. 3 Infrared soldering profile for Chip Resistors

Table 1. Infrared soldering condition for Chip Resistors

Temperature Condition

Exposure Time

Average ramp-up rate (217qC to 260qC)

Less than 3qC/second

Between 150 and 200qC

Between 60-120 seconds

> 217qC

Between 60-150 seconds

Peak Temperature

260ºC +0/-5qC

Time within 245qC

Min. 30 seconds

Ramp-down rate (Peak to 217qC)

Less than 6qC/second

Time from 25qC to Peak

No greater than 480 seconds