AN-9072

www.fairchildsemi.com AN-9072 Smart Power Module Motion-SPM™ in µMini-DIP SPM Mounting Guidance Mounting Guidance This application note shows the electric spacing and mounting guidance of Mini-DIP SPM. Electric Spacing The electric spacing specification of Mini-DIP SPM is shown in Table 1. Table 1. Typical Electric Spacing of Mini-DIP SPM Creepage Clearance Distance [mm] [mm] Between Power Terminals Between Control Terminals Between Terminals & Heat Sink 3.08 2.35 2.05 3.28 4.95 2.05 Figure 1. Mounting Screws Fastening Order: Pre-Screwing: 1 → 2; Final Screwing: 2 → 1 Notes: 1. Do not over torque when mounting screws. Excess mounting torque may cause ceramic cracks, as well as screw and heat-sink damage. 2. Avoid one-side tightening stress, Figure 1 shows the recommended torque order for mounting screws. Uneven mounting can cause the SPM ceramic substrate to be damaged. The pre-screwing torque is set to 20~30% of maximum torque rating. Mounting Method and Precautions When installing a module to a heat sink, excessive uneven fastening force might apply stress to inside chips, which can lead to damage or degradation of the device. An example of recommended fastening order is shown in Figure 1. Table 2. Mounting Torque and Heat Sink Flatness Specifications Conditions See Figure 2 See Figure 3 Recommended 0.7N·m Recommended 7.1kg·m Parameter Device Flatness Heat Sink Flatness Mounting Torque W eight Screw: M3 Limits Min. 0 -50 0.6 6.2 Typ. Max. +120 +100 0.8 8.1 Units µm µm N·m kg·cm g 0.7 7.1 11 Note: 3. Recommend using SEMS screw (include spring/plain washer, M3) in fastening screws. © 2009 Fairchild Semiconductor Corporation Rev. 1.0.2 • 4/7/11 www.fairchildsemi.com AN-9072 APPLICATION NOTE To get the most effective heat dissipation, it is necessary to enlarge the contact area as much as possible, which minimizes the contact thermal resistance. Properly apply thermal-conductive grease over the contact surface between a module and heat sink, which is also useful for preventing the contact surface from corrosion. Ensure the grease has stable quality and long-term endurance within a wide operating temperature range. Use a torque wrench to fasten up to the specified to torque rating. Exceeding the maximum torque limitation might cause a module to be damaged or degraded. Pay careful attention not to have any dirt remaining on the contact surface. Thermal Compound Figure 2. Measurement Point of Package Surface Flatness Note: 4. The measurement point of flatness of the package surface is package center point compared with outside four points. Use a minimum 150µm layer of thermal grease to the module base plate or to the heat sink. While fastening the module, a rim of thermal compound must be observed around the mounted module. Fixing Sequence Fix all screws 0.5N·m under (by hand or driver). Apply impact torque maximum 0.8N m crosswise. Use recommended SEMS screw (included spring/plain washer M3). Figure 3. Measurement Point of Heat Sink Flatness Figure 4. SEMS Screw (Size M3, Spring Washer 5.0Φ, Plain Washer 7.5Φ) © 2009 Fairchild Semiconductor Corporation Rev. 1.0.2 • 4/7/11 www.fairchildsemi.com 2 AN-9072 APPLICATION NOTE Related Datasheets FNX4XX60X — Smart Power Module Motion-SPM™ AN-9070 — Smart Power Module Motion-SPM™ in µMini-DIP SPM User Guide AN-9071 — Smart Power Module Motion-SPM™ in µMini-DIP SPM Thermal Performance Information DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION, OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, or (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. © 2009 Fairchild Semiconductor Corporation Rev. 1.0.2 • 4/7/11 www.fairchildsemi.com 3