Datasheet MTD20P06HDL (Motorola) - 9

MTD20P06HDL
SOLDER STENCIL GUIDELINES
ÇÇÇÇÇÇ Prior to placing surface mount components onto a printed ÇÇÇÇÇÇÇÇ ÇÇ circuit board, solder paste must be applied to the pads. Solder ÇÇÇÇÇÇÇÇ ÇÇ stencils are used to screen the optimum amount. These SOLDER PASTE stencils are typically 0.008 inches thick and may be made of ÇÇÇÇÇÇÇÇ ÇÇ OPENINGS brass or stainless steel. For packages such as the SC–59, ÇÇÇÇÇÇÇÇ ÇÇ SC–70/SOT–323, SOD–123, SOT–23, SOT–143, SOT–223, SO–8, SO–14, SO–16, and SMB/SMC diode packages, the ÇÇÇÇÇÇÇÇ STENCIL stencil opening should be the same as the pad size or a 1:1 ÇÇÇÇÇÇÇÇ registration. This is not the case with the DPAK and D2PAK packages. If one uses a 1:1 opening to screen solder onto the
Figure 17. Typical Stencil for DPAK and
drain pad, misalignment and/or “tombstoning” may occur due
D2PAK Packages
to an excess of solder. For these two packages, the opening in the stencil for the paste should be approximately 50% of the tab area. The opening for the leads is still a 1:1 registration. Figure 17 shows a typical stencil for the DPAK and D2PAK packages. The pattern of the opening in the stencil for the drain pad is not critical as long as it allows approximately 50% of the pad to be covered with paste.
SOLDERING PRECAUTIONS
The melting temperature of solder is higher than the rated • When shifting from preheating to soldering, the maximum temperature of the device. When the entire device is heated temperature gradient shall be 5°C or less. to a high temperature, failure to complete soldering within a • After soldering has been completed, the device should be short time could result in device failure. Therefore, the allowed to cool naturally for at least three minutes. following items should always be observed in order to Gradual cooling should be used as the use of forced minimize the thermal stress to which the devices are cooling will increase the temperature gradient and result subjected. in latent failure due to mechanical stress. • Always preheat the device. • Mechanical stress or shock should not be applied during • The delta temperature between the preheat and soldering cooling. should be 100°C or less.* • When preheating and soldering, the temperature of the * Soldering a device without preheating can cause excessive leads and the case must not exceed the maximum thermal shock and stress which can result in damage to the temperature ratings as shown on the data sheet. When device. using infrared heating with the reflow soldering method, the difference shall be a maximum of 10°C. * Due to shadowing and the inability to set the wave height to • The soldering temperature and time shall not exceed incorporate other surface mount components, the D2PAK is 260°C for more than 10 seconds. not recommended for wave soldering. Motorola TMOS Power MOSFET Transistor Device Data 9