1.IR for SMD Soldering Instructions Table 1 IR condition Profile Feature Preheat & Soak Temperature min (Tsmin) Temperature max (Tsmax) Time (Tsmin to Tsmax)(ts) Average ramp-up rate (Tsmax to Tp) Liquidous temperature (TL) Time at liquidous (tL) Peak package body temperature (Tp)* Pb-Free Assembly 150 ℃ ～200 ℃ 60-120 seconds 3 ℃/second max. 217 ℃ 60-150 seconds See classiｆｉcation temp in Table 4.2 Time (tp)*＊ within 5℃ of the 30** seconds specｉｆｉｅd classi cation temperature (Tc) Average ramp-down rate (Tp to Tsmax) 6 ℃/second max. Time 25℃ to peak temperature 8 minutes max. * Tolerance for peak proｆｉｌe temperature (Tp) is defined as a supplier minimum and a user maximum. ** Tolerance for time at peak profile temperature (tp) is defined as a supplier minimum and a user maximum. Note 1: All temperatures refer to the center of the package, measured on the package body surface that is facing up during assembly reflow (e.g., live-bug). If parts are reflowed in other than the normal live-bug assembly reflow orientation (i.e., dead-bug), Tp shall be within ±2℃ of the live-bug Tp and still meet the Tc requirements, otherwise, the profile shall be adjusted to achieve the latter. To accurately measure actual peak package body temperatures refer to JEP140 for recommended thermocouple use. Note 2: Reflow profiles in this document are for classification/ preconditioning and are not meant to specify board assembly profiles. Actual board assembly profiles should be developed based on specific process needs and board designs and should not exceed the parameters in Table 2. For example, if Tc is 260℃ and time tp is 30 seconds, this means the following for the supplier and the user. For a supplier: The peak temperature must be at least 260℃. The time above 255℃ must be at least 1／3 30 seconds. For user: The peak temperature must not exceed 260℃. The time above 255℃ must not exceed 30 seconds. Note 3: All components in the test load shall meet the classification profile requirements. Note 4: SMD packages classified to a given moisture sensitivity level by using Procedures or Criteria defined within any previous version of J-STD-020, JESD22-A112 (rescinded), IPC-SM-786 (rescinded) do not need to be reclassified to the current revision unless a change in classification level or a higher peak classification temperature is desired. Table 2. Pb-Free Process -Classification Temperatures (Tc) Package Thickness <1.6 mm 1.6 mm -2.5 mm >2.5 mm Volume mm3 <350 260 ℃ 260 ℃ 250 ℃ Volume mm3 350 -2000 260 ℃ 250 ℃ 245 ℃ Reflow Theoretical Profile 2. wave peak flow solder Temp. 260±5℃ time 10±1sec 3. iron solder Temp. 350±5℃ time 3±0.5sec 2／3 Volume mm3 >2000 260 ℃ 245 ℃ 245 ℃ The Temperature Curve Infrared Of Reflow 图 1： Lead free Infrared Reflow TMPERATURE ℃ 250~260℃ 217℃ 60s ~150s ABOVE SOLDER MELTING POINT 150℃ PREHEAT ZONE 30 60 90 120 ACTIVATES SOLDER FLUX 150 180 210 240 270 300 330 360 TIME IN SECONDS 图 2： TMPERATURE ℃ Pb—Sn Infrared Reflow 235~240℃ 60s ~ 150s 183℃ ABOVE SOL DER 100℃ MELTING POINT PREHEAT ZONE 30 60 ACTIVATES S OLDER F LUX 90 120 150 180 210 240 TIME IN SECONDS CUSTOMER： APPROVDED： APPROVED： CHECKED： CHECKED： DRAWN： 3／3 270 300 330 360