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AT91SAM7A2 - Summary

6021AS–ATARM–03/04

Soldering

Profile

Table 7 gives the recommended soldering profile from J-STD-20.

Small packages may be subject to higher temperatures if they are reflowed in boards with

larger components. In this case, small packages may have to withstand temperatures of up to

235

°C, not 220°C (IR reflow).

Recommended package reflow conditions depend on package thickness and volume. See

Table 8 below.

Notes:

1. The packages are qualified by Atmel by using IR reflow conditions, not convection or VPR.

2. By default, the package level 1 is qualified at 220

°C (unless 235°C is stipulated).

3. The body temperature is the most important parameter but other profile parameters such as

total exposure time to hot temperature or heating rate may also influence component

reliability.

A maximum of three reflow passes is allowed per component.

Table 7. Soldering Profile

Convection or

IR/Convection

VPR

Average Ramp-up Rate (183

°C to Peak)

3

°C/sec. max.

10

°C/sec.

Preheat Temperature 125

°C ±25°C

120 sec. max

Temperature Maintained Above 183

°C

60 sec. to 150 sec.

Time within 5

°C of Actual Peak Temperature

10 sec. to 20 sec.

60 sec.

Peak Temperature Range

220 +5/-0

°C or

235 +5/-0

°C

215 to 219

°C or

235 +5/-0

°C

Ramp-down Rate

6

°C/sec.

10

°C/sec.

Time 25

°C to Peak Temperature

6 min. max

Table 8. Recommended Package Reflow Conditions

(1, 2, 3)

Parameter

Temperature

Convection

220 +5/-0

°C

VPR

215 to 219

°C

IR/Convection

220 +5/-0

°C