Approval sheet
TEST AND REQUIREMENTS
TEST
PROCEDURE
REQUIREMENT
Temperature
Coefficient of
Resistance
( TCR )
Natural resistance change per change in degree
centigrade.
Test temperature –55 ~ +125°C
As defined in P.3
R2 − R
×106 (ppm/°C)
1
R
(
t2 − t1
)
1
R1 : Resistance at reference temperature
R2 : Resistance at test temperature
t1 : 25°C
Short time
Permanent resistance change after 2 second application
∆R/R max. ±1%
overload ( STOL ) of a current 2.5 times RCWC specified.
no visible damage
Sub-Clause 4.13
Resistance to
soldering heat
Un-mounted chips 10±0.5 seconds, 260±5ºC
no visible damage
∆ R/R max. ±1%
Sub-clause 4.18
Solderability
Termination Sn base (lead free) : Un-mounted chip good tinning (>95% covered)
completely immersed in a lead free solder bath,
235°C±5°C, 2±0.5 sec
Sub-clause 4.17
no visible damage
Temperature
cycling
no visible damage
1. 30 minutes at -55°C±3°C,
2. 2~3 minutes at room temperature,
3. 30 minutes at +125°±3°C,
∆R/R max. ±1%
Sub-clause 4.19
4. 2~3 minutes at room temperature,
Total 5 continuous cycles
Load life
(endurance)
70±2ºC, 1000 hours, loaded with rated current,
1.5 hours on and 0.5 hours off
∆R/R max. ±5%
no visible damage
Sub-clause 4.25.1
Steady state in
Humidity
1000hrs without current applied in humidity chamber
∆R/R max. ±5%
controller at 40°C±2°C and 90~95% relative humidity
no visible damage
Sub-clause 4.24
Bending strength
Sub-clause 4.33
Resistors mounted on a 90mm glass epoxy resin
PCB(FR4); bending : 3 mm,
∆R/R max. ±1%
no visible damage
No visible damage
Adhesion
5N, 10±1s ( WW02C: 3N)
Sub-clause 4.32
Page 6 of 8
ASC_WWxxC_V07
Jan 2014