Recommended Reflow Profile
255
230
217
200
180
150
120
80
25
0
P1
HEAT
UP
50
100
P2
SOLDER PASTE DRY
150
200
P3
SOLDER
REFLOW
250
P4
COOL DOWN
300
t-TIME
(SECONDS)
R1
MAX 260C
R3
R4
T - TEMPERATURE (˚C)
R2
60 sec to 90 sec
Above 217 C
R5
Process Zone
Heat Up
Solder Paste Dry
Solder Reflow
Cool Down
Time maintained above °C
Peak Temperature
Symbol
P, R
P, R
P3, R3
P3, R4
P4, R5
DT
5°C to 50°C
50°C to 00°C
00°C to 55°C
55°C to 00°C
00°C to 5°C
> °C
60°C
> 55°C
5°C to 60°C
Maximum
DT/Dtime
or Duration
3°C/s
00s to 80s
3°C/s
-6°C/s
-6°C/s
60s to 90s
0s to 40s
8mins
Time within 5°C of actual Peak Temperature
Time 5°C to Peak Temperature
The reflow profile is a straight-line representation of
a nominal temperature profile for a convective reflow
solder process. The temperature profile is divided into
four process zones, each with different
DT/Dtime
tem-
perature change rates or duration. The
DT/Dtime
rates or
duration are detailed in the above table. The tempera-
tures are measured at the component to printed circuit
board connections.
In process zone P1, the PC board and APDS-9006 pins
are heated to a temperature of 150°C to activate the flux
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 APDS-9006 pins.
Process zone P2 should be of sufficient time duration (60
to 120 seconds) to dry the solder paste. The temperature
is raised to a level just below the liquidus point of the
solder, usually 200°C (392°F).
Process zone P3 is the solder reflow zone. In zone P3,
the temperature is quickly raised above the liquidus
point of solder to 255°C (491°F) for optimum results. The
dwell time above the liquidus point of solder should be
between 20 and 40 seconds. It usually takes about 20
seconds to assure proper coalescing of the solder balls
into liquid solder and the formation of good solder con-
nections. Beyond a dwell time of 40 seconds, the inter-
metallic growth within the solder connections becomes
excessive, resulting in the formation of weak and un-
reliable connections. The temperature is then rapidly
reduced to a point below the solidus temperature of the
solder, usually 200°C (392°F), 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 APDS-9006 pins to change dimensions evenly,
putting minimal stresses on the APDS-9006.
It is recommended to perform reflow soldering no more
than twice.
9
AVAGO [ AVAGO TECHNOLOGIES LIMITED ]
