Copyright © 2015 Future Technology Devices International Limited

33

FT234XD USB TO BASIC UART IC

Version 1.2

Document No.: FT_000753 Clearance No.: FTDI#324

9.3 Solder Reflow Profile

The FT234XD is supplied in a Pb free DFN-12 package. The recommended solder reflow profile is shown

in Figure 9.35.

Figure 9.3 FT234XD Solder Reflow Profile

The recommended values for the solder reflow profile are detailed in Table 9.1. Values are shown for both

a completely Pb free solder process (i.e. the FT234XD is used with Pb free solder), and for a non-Pb free

solder process (i.e. the FT234XD is used with non-Pb free solder).

Profile Feature

Pb Free Solder Process

Non-Pb Free Solder Process

3°C / second Max.

3°C / Second Max.

Preheat

150°C

200°C

60 to 120 seconds

100°C

150°C

60 to 120 seconds

Time Maintained Above Critical Temperature

217°C

60 to 150 seconds

183°C

60 to 150 seconds

260°C

240°C

Time within 5°C of actual Peak Temperature

20 to 40 seconds

20 to 40 seconds

Ramp Down Rate

6°C / second Max.

6°C / second Max.

8 minutes Max.

6 minutes Max.

Table 9.1 Reflow Profile Parameter Values

Critical Zone: when

T is in the range

T to T

Time, t (seconds)

25

P

T = 25º C to T

t

Preheat

S

t

L

Ramp Up

L

p

Ramp

Down

T Max

S

T Min

S