Process Zone Symbol T
Maximum T/time
or Duration
Heat Up P1, R1 25°C to 150°C 3°C/s
Solder Paste Dry P2, R2 150°C to 200°C 100 s to 180 s
Solder Re ow P3, R3 200°C to 260°C 3°C/s
P3, R4 260°C to 200°C -6°C/s
Cool Down P4, R5 200°C to 25°C -6°C/s
Time maintained above liquidus point, 217° C > 217°C 60 s to 90 s
Peak Temperature 260°C –
Time within 5° C of actual Peak Temperature – 20 s to 40 s
Time 25° C to Peak Temperature 25°C to 260°C 8 mins
The re ow pro le is a straight-line representation of
a nominal temperature pro le for a convective re ow
solder process. The temperature pro le is divided into
four process zones, each with di erent T/time tem-
perature change rates or duration. The T/time rates or
duration are detailed in the above table. The temperatures
are measured at the component to printed circuit board
connections.
In process zone P1, the PC board and component pins
are heated to a temperature of 150°C to activate the ux
in the solder paste. The temperature ramp up rate, R1, is
limited to 3°C per second to allow for even heating of both
the PC board and component pins.
Process zone P2 should be of su cient time duration (100
to 180 seconds) to dry the solder paste. The temperature is
raised to a level just below the liquidus point of the solder.
Process zone P3 is the solder re ow zone. In zone P3, the
temperature is quickly raised above the liquidus point of
solder to 260°C (500°F) for optimum results. The dwell time
above the liquidus point of solder should be between 60
and 90 seconds. This is to assure proper coalescing of the
solder paste into liquid solder and the formation of good
solder connections. Beyond the recommended dwell time
the intermetallic growth within the solder connections
becomes excessive, resulting in the formation of weak and
unreliable connections. The temperature is then rapidly
reduced to a point below the solidus temperature of the
solder to allow the solder within the connections to freeze
solid.
Process zone P4 is the cool down after solder freeze. The
cool down rate, R5, from the liquidus point of the solder to
25°C (77°F) should not exceed 6°C per second maximum.
This limitation is necessary to allow the PC board and
component pins to change dimensions evenly, putting
minimal stresses on the component.
It is recommended to perform re ow soldering no more
than twice.
Recommended Re ow Pro le
50
100 150 200 250 300
t-TIME
(SECONDS)
25
80
120
150
180
200
230
255
0
T - TEMPERATURE (°C)
R1
R2
R3
R4
R5
217
MAX 260°C
60 sec to 90 sec
Above 217°C
P1
HEAT
UP
P2
SOLDER PASTE DRY
P3
SOLDER
REFLOW
P4
COOL DOWN
For product information and a complete list of distributors, please go to our web site: www.avagotech.com
Avago, Avago Technologies, and the A logo are trademarks of Avago Technologies in the United States and other countries.
Data subject to change. Copyright © 2015–2016 Avago Technologies. All rights reserved.
AV02-4755EN - October 21, 2016
