Wire and Film Technologies Division

Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com

February 2009 Issue Page 4 of 4

• 4222 South Staples Street • Corpus Christi Texas 78411 USA

OARS-3

Open Air Sense Resistors

Metal Alloy Strip

Note 1

: Package volume excludes external

terminals (balls, bumps, lands, leads) and/or

non-integral heat sinks.

Note 2

: The maximum component temperature

reached during reflow depends on package

thickness and volume. The use of convection

reflow processess reduces the thermal gradients

between packages. However, thermal gradients

due to differences in thermal mass of SMD pack-

ages may still exist.

Note 3

: Components intended for use in “lead-

free” assembly process shall be evaluated using

the “lead-free” peak temperature and profiles

defined in Table 1, 2 and reflow profile whether

or not lead-free.

Tabel 1: SnPb Eutectic Process -

Package Peak Reflow Temperatures

Package

Thickness

Volume mm3 < 350

Volume mm3 ≥ 350

< 2.5 mm

240 +0/-5°C

225 +0/-5°C

≥ 2.5 mm

225 +0/-5°C

225 +0/-5°C

Tabel 2: Pb-free Process -

Package Peak Reflow Temperatures

Package

Thickness

Volume mm3

< 350

Volume mm3

350 - 2000

Volume mm3

> 2000

< 1.6 mm

260°C *

260°C *

260°C *

1.6 mm - 2.5 mm

260°C *

250°C *

245°C *

≥ 2.5 mm

250°C *

245°C *

245°C *

* Tolerance: The device manufacturer/supplier shall assure process compat-

ibility up to and including the stated classification temperature at the rated MSL

level.

Note 1

: All temperatures refer

to topside of the package,

measured on the package

body surface.

Note 2

: Time within 5 °C of

actual peak temperature (tp)

specified for the reflow profiles

is a “supplier” minimum and a

“user” maximum.

Profile Feature

Sn-Pb Eutectic

Assembly

Pb-Free

Assembly

Average Ramp-up rate (Tsmax to Tp)

3°C / second max.

3°C / second max.

Preheat

- Temperature Min (Tsmin)

- Temperature Max (Tsmax)

- Time (Tsmin to Tsmax) (ts)

100°C

150°C

60 -120 seconds

150°C

200°C

60 -180 seconds

Time maintained above

- Temperature (TL)

- Time (tL)

183°C

60 - 150 seconds

217°C

60 - 150 seconds

Peak Temperature (TP)

See Table 1

See Table 2

Time within 5°C of actual Peak Temperature (tp)2

10 - 30 seconds

20 - 40 seconds

Ramp-down Rate

6°C / second max.

6°C / second max.

Time 25°C to Peak Temperature

6 minutes max.

8 minutes max.

Sn-Pb Eutectic and Pb-Free Reflow Profiles

Time

Critical Zone

T

Ramp-down

Ramp-up

t 25°C to Peak

T

P

T

L

T

smax

T

smin

t

s

Preheat

t

L

25

t

P

* Based on Industry Standards and IPC recommendations

IRC Solder Reflow Recommendations