CHAPTER 6

THERMAL DESIGN CONSIDERATIONS

page

Introduction 6 - 2

Thermal resistance 6 - 2

Junction temperature 6 - 2

Factors affecting Rth(j-a) 6 - 2

Thermal resistance test methods 6 - 3

Test procedure 6 - 3

Forced air factors for thermal resistance 6 - 4

Thermal resistance data - assumptions and precautions 6 - 5

Thermal resistance (Rth(j-a)) data 6 - 6

Thermal resistance (Rth(j-c)) data tables - power packages 6 - 24 Philips IC Packages

Thermal design considerations Chapter 6

INTRODUCTION FACTORS AFFECTING Rth(j-a) The ability to describe the thermal performance There are several factors which affect the characteristic characteristics of a IC package is thermal resistance of IC packages. Some of the more becoming increasingly crucial. With increased power significant of these include the test board configuration, densities, improved reliability and shrinking system sizes, the material, the design of the lead frame and the cooling of IC packages has become a challenging task the moulding compound. for design engineers. The situation is further exacerbated by the demand for ever decreasing sizes of electronic Test board Configuration devices because, in general, decreasing the size of an An IC package’s thermal resistance highly depends on the electronic package decreases the thermal performance. (PCB) on which the package is The designer must carefully balance the benefits of mounted. The copper traces and thermal vias on the PCB miniaturization and performance against the potential provide the major heat dissipation path of the package, reduction in reliability of electronic components resulting therefore the configuration and the size of the copper from high operating temperatures. traces play a significant role in affecting Rth(j-a). For test purpose, JEDEC standards (EIA/JEDEC51-3 and others) THERMAL RESISTANCE specify two categories of test boards: low effective thermal conductivity test board (low K board) and high effective The ability of a particular semiconductor package to thermal conductivity test board (high K board). The low K dissipate heat to its environment is expressed in terms of board is a single sided board with only fine signal traces, thermal resistance (R ). This single entity describes th(j-a) the high K board is a board with two signal layers and two the heat path impedance from the active surface of the power (or ground) layers. The real application board is (junction) to the ambient operating almost always different from the standard test boards, environment. R can be expressed by its constituents th(j-a) however, the thermal resistance measured from the as follows: standard test board provides basic comparable Rth(j-a) =Rth(j-c) +Rth(c-a) information of the IC package thermal resistance. R is the impedance from junction to case (outside th(j-c) Lead Frame Material surface of package) and Rth(c-a) is the impedance from case to ambient. It is sometimes useful to use only the The lead frame material is one of the more important Rth(c-a) to describe high performance packages where factors in IC package thermal resistance. In early dual case temperatures are important and externally attached in-line packages (DIPs), a Ni/Fe alloy (A42) was the heat radiators may need to be attached. In these cases the material of choice for lead frames as it provided a good overall Rth(j-a) will also include the contribution of the heat combination of strength and formability as well as radiator. assembly process compatibility. However, with the continued miniaturization of IC packages and the need for increased electrical conductivity for advanced ICs, a JUNCTION TEMPERATURE switch to sophisticated copper alloys was required. With the Rth(j-a) of a package known, the rise in junction Copper alloy lead frames offer several advantages over temperature (Tj) with respect to the ambient temperature A42: (Tamb) can be determined at a given power dissipation (Pd) • they have a high thermal conductivity which reduces of the semiconductor device: thermal resistance, essential for packages such as the

Tj =(Rth(j-a) × Pd)+Tamb Shrink Small Outline Package (SSOP) and Thin Shrink Small Outline Package (TSSOP) Where: • their improved electrical conductivity enhances the Tj = junction temperature (°C) electrical performance of a package Rth(j-a) = thermal resistance junction to ambient (K/W) Pd = power dissipated (W) Most encapsulated packages produced by Philips ° Tamb = ambient temperature ( C) Semiconductors incorporate copper alloy lead frames into their design. It’s important to note that a lower Rth(j-a) indicates a higher thermal performance.

April 2000 6 - 2 Philips Semiconductors IC Packages

Thermal design considerations Chapter 6

Lead Frame Design The design of a lead frame is another significant contributing factor to thermal resistance. The most Box important design aspect is the IC attach-pad size and tie bar design. However, the lead frame designer is often faced with fixed parameters such as die size and limitations, which reduce lead frame design Package flexibility.

Substrate Moulding Compound Thermocouple Moulding compounds also determine IC package thermal Cables resistance. The mould compounds used by Philips Semiconductors are optimized for high purity and quality to

provide good thermal performance and reliability.

MSC599

Heat Spreaders Fig.1 The test fixture in still air. The option of a heat spreader, or heat slug, within some packages can improve thermal behaviour by spreading the heat over a larger area of the package, and so improve The forward voltage drop of a calibrated Rth(j-a) or Rth(j-c). incorporated into a special IC is used to correlate a junction temperature change in the IC package to be Adhesive and Plating Type tested. As the power dissipation is known, the thermal resistance can be calculated using the following equation: Other package related factors include die attach adhesive ∆ () and lead frame plating type, but the actual influence on Tj Tj – Tamb Rth() j– a ==------thermal resistance is small owing to the fine geometry of Pd Pd these factors. Where: Rth(j-a) = thermal resistance junction to ambient (°C/W) ° THERMAL RESISTANCE TEST METHODS Tj = junction temperature ( C) Pd = power dissipated (W) Philip Semiconductors uses what is commonly called the T = ambient temperature (°C) Temperature Sensitive Parameter (TSP) method which amb meets EIA/JEDEC Standards EIA/JESD51-1, EIA/JESD51-2 and EIA/JESD51-3. A typical test fixture in TEST PROCEDURE still air is shown in Fig.1. The enclosure is a box with an The TSP diode on the semiconductor device is calibrated inside dimension of 1 ft3 (0.0283 m3). The enclosure and using a constant temperature oil bath and a constant fixtures are constructed from an insulating material with a current power supply (see Fig.2). Calibration temperatures low thermal conductance, and all seams thoroughly sealed are typically 25 °C and 100 °C with a measured accuracy to ensure there is no airflow through the enclosure. The IC of ±0.1 °C. The calibration current must be kept low and package is then positioned in the geometric center of the constant to avoid significant junction heating. The enclosure. temperature coefficient (K-factor) shown in Fig.3 is calculated using the following equation: () T2 – T1 K = ()------VF2 – VF1 Where: K = temperature coefficient (°C/mV) T2 = high test temperature (°C) T1 = low test temperature (°C) VF2 = forward voltage at T2 (mV) VF1 = forward voltage at T1 (mV)

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Thermal design considerations Chapter 6

Where: VF(amb) = forward voltage of TSP at ambient handbook, halfpageI = CONSTANT temperature (mV) VF(s) = forward voltage of TSP at steady-state temperature (mV)

OIL BATH VH = heating voltage (V) MAINTAINED AT CONSTANT IH = heating current (A) VF TEMPERATURE

D FORCED AIR FACTORS FOR THERMAL RESISTANCE I F Many applications with ICs have the benefit of forced air cooling by fans or other means. The junction to moving-air D = ON DIE TSP DIODE thermal resistance can be measured by placing the test MSB474 setup inside a low velocity wind tunnel (see Fig.4). The test board and device under test are supported with minimal Fig.2 Test procedure. obstruction to the air flow.

ANEMOMETER FLOW STRAIGHTENER TEST MSB473 PART FAN handbook,V F halfpage(V) AIR FLOW VF1 35.5 (14) 43 (19) VF2

58.5 (23) 132 (52) DIAMETER = 15 (6) 183 (72) not to scale MSB475 T T o 1 2 T j ( C)

Fig.3 VF as a function of Tj. Fig.4 Wind tunnel - dimensions in cm (inches).

With the K-factor determined, Rth(j-a) can be calculated by The average effect of airflow on thermal resistance for powering up the device at ambient conditions and package types at a particular air flow rate can be measuring the forward voltage drop across the TSP diode determined using a “derating” curve (see Fig.5). When after temperature equilibrium. Manipulating the original using derating curves, it’s important to note that the variety thermal resistance equation with the K-factor, the Rth(j-a) of of sizes in a package type group has been averaged. See the package can be determined: the following section on “Thermal resistance data - ∆ ()()assumptions and precautions” concerning airflow. Tj Tj – Tamb KVF() amb – VFs() Rth() j– a ==------=------× Pd Pd VH IH

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Thermal design considerations Chapter 6

3. The operating environment temperature must be used as the ambient temperature when calculating junction MSC554 temperatures in an application. The temperatures 0 handbook, halfpage percent change inside an electronic enclosure are generally higher in Rth(j-a) (%) than the room temperature. −10 SO 4. When using airflow derating curves (see Fig.5), please SOL note that in actual applications where airflow is SDIP available, the flow dynamics may be more complex −20 and turbulent than in a wind tunnel. Also, the many different sizes of packages in a package family such −30 as QFP have been averaged to give one curve for ease-of-use. Lastly, the test boards used in the wind DIP tunnel contribute significantly to forced convection −40 LQFP heat transfer and may not be similar to an actual PLCC/QFP application PC board, especially its size.

−50 5. Thermal resistance will vary slightly as a function of 051234 input power. Generally, as the power input increases, air flow (m/s) thermal resistance decreases. Thermal resistance changes approximately 5% for a 100% power change. Fig.5 Average effect of airflow on Rth(j-a). 6. Thermal resistance data for some packages were not available at the time of publication. Please contact Philips Semiconductors for information on packages THERMAL RESISTANCE DATA - not listed in this handbook. ASSUMPTIONS AND PRECAUTIONS 7. All data presented are accurate to approximately The graphical data presented in this section are based on ±15%. For more specific information regarding an measurements, modelling and estimations. As with all application, please contact Philips Semiconductors. data, some assumptions and contributing factors should 8. Philips Semiconductors is evaluating a new technique, be noted: which was described in the ESPRIT project DELPHI, 1. The “measured” thermal resistance of an IC package to thermally characterize IC packages. This results in is highly dependent on the configuration and size of a description of the package by means of a resistor the test board. Data may not be comparable between network, the so-called compact model. This resistor different semiconductor manufacturers because the network gives an accurate model of the package and test boards may not be the same. Also, the thermal is valid for all practical environments. It is expected performance of packages for a specific application that these models can be imported into system- and may be different than presented here because the PCB-level analyses tools in the near future. If you configuration of the application boards may be require more information about compact models, different than the test boards. Philip Semiconductors please contact the ATO-Innovation office in Nijmegen, uses low effective thermal conductivity test boards for the Netherlands tel. +31-24-3533085 or most of its packages. fax +31-24-3533350. 2. Device standoff is a factor in determining thermal resistance especially for surface mounted packages such as SO and QFP packages. The same package from two different manufacturers will often have different standoff from the test boards. In general, high standoff corresponds to a higher thermal resistance.

April 2000 6 - 5 Philips Semiconductors IC Packages

Thermal design considerations Chapter 6

THERMAL RESISTANCE (Rth(j-a)) DATA

MBK303 MBK305 120 100 handbook, halfpage handbook, halfpage Rth(j-a) R th(j-a) (K/W) (K/W) 90 110

80

100 70

90 60 0 10 20 30 0 10 20 30 die size (mm2) die size (mm2)

Fig.6 DIP8 (300 mil). Fig.7 DIP14/16 (300 mil).

MBK304 80 handbook, halfpage

MBK307 90 Rth(j-a) handbook, halfpage (K/W) Rth(j-a) (K/W) 70

80

60

70

50 0 10 20 30 die size (mm2) 60 0 10 20 30 die size (mm2)

Fig.8 DIP18 (300 mil). Fig.9 DIP20 (300 mil).

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Thermal design considerations Chapter 6

MBK306 MBK308 65 70 handbook, halfpage handbook, halfpage Rth(j-a) R th(j-a) (K/W) (K/W) 65 60

60

55 55

50 50 0 10 20 30 0 10 20 30 die size (mm2) die size (mm2)

Fig.10 DIP22 (400 mil). Fig.11 DIP24 (300 mil).

MBK309 MBK311 70 60 handbook, halfpage handbook, halfpage R R th(j-a) th(j-a) (K/W) (K/W) 55 60

50

50 45

40 40 0 10 20 30 40 0 10 20 30 40 die size (mm2) die size (mm2)

Fig.12 DIP24 (400 mil). Fig.13 DIP24 (600 mil).

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Thermal design considerations Chapter 6

MBK310 MBK312 55 50 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

50 45

45 40

40 35 0 10 20 3040 50 0 20 40 60 80 die size (mm2) die size (mm2)

Fig.14 DIP28 (600 mil). Fig.15 DIP40 (600 mil).

MBK314 MBK319 50 22 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 20

45 18

16 40

14

35 12 0 20 40 60 80 0 100200 300 400 500 die size (mm2) die size (mm2)

Fig.16 DIP48 (600 mil). Fig.17 HSQFP240 (32 × 32 × 3.4 mm).

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Thermal design considerations Chapter 6

MBK316 MBK318 100 100 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

95 90

90 80

85 70

80 60 0 51015 0 10 20 30 die size (mm2) die size (mm2)

Fig.18 LQFP32 (5 × 5 × 1.4 mm) Fig.19 LQFP32 (7 × 7 × 1.4 mm).

MBK320 MBK321 70 90 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 65 80

60

70 55

50 60 0 20 40 60 80 0 10 20 30 die size (mm2) die size (mm2)

Fig.20 LQFP44 (10 × 10 × 1.4 mm) Fig.21 LQFP48 (7 × 7 × 1.4 mm).

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Thermal design considerations Chapter 6

MBK323 MBK325 80 70 handbook, halfpage handbook, halfpage Rth(j-a) R th(j-a) (K/W) (K/W) 65 75

60

70 55

65 50 0 10 20 30 0 2040 60 80 die size (mm2) die size (mm2)

Fig.22 LQFP64 (7 × 7 × 1.4 mm). Fig.23 LQFP64 (10 × 10 × 1.4 mm).

MBK322 MBK324 60 60 handbook, halfpage handbook, halfpage R R th(j-a) th(j-a) (K/W) (K/W) 55 55

50

50 45

45 40 0 20 4060 80 0 20 40 60 80 100 die size (mm2) die size (mm2)

Fig.24 LQFP80 (12 × 12 × 1.4 mm). Fig.25 LQFP100 (14 × 14 × 1.4 mm).

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Thermal design considerations Chapter 6

MBK326 MBK327 60 82 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

55 78

50 74

45 70

40 66 0 20 4060 80 100 0 10 20 30 die size (mm2) die size (mm2)

Fig.26 LQFP128 (14 × 14 × 1.4 mm). Fig.27 PLCC20 (310 mil).

MBK329 MBK328 80 55 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

70 50

60 45

50 40 0 10 2030 40 0 20 4060 80 100 die size (mm2) die size (mm2)

Fig.28 PLCC28 (410 mil). Fig.29 PLCC44 (610 mil).

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Thermal design considerations Chapter 6

MBK330 MBK332 55 50 handbook, halfpage handbook, halfpage R Rth(j-a) th(j-a) (K/W) (K/W) 48 50

46

45

44

40 42

35 40 0 20 40 60 80 100 0 4080 120 160 die size (mm2) die size (mm2)

Fig.30 PLCC52 (710 mil). Fig.31 PLCC68 (910 mil).

MBK333 MBK335 42 75 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 40 70

38 65

36 60

34 55

32 50 0 20 40 60 80 100 0 10 2030 40 50 die size (mm2) die size (mm2)

Fig.32 PLCC84 (1110 mil). Fig.33 QFP44 (10 × 10 × 1.75 mm).

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Thermal design considerations Chapter 6

MBK337 MBK336 90 70 handbook, halfpage handbook, halfpage R Rth(j-a) th(j-a) (K/W) (K/W) 65 80

60

70

55

60 50

50 45 0 2040 60 80 0 10 20 30 40 50 die size (mm2) die size (mm2)

Fig.34 QFP44 FeNi (14 × 14 × 2.2 mm). Fig.35 QFP52 (10 × 10 × 2 mm).

MBK338 MBK339 60 55 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

55 50

50 45

45 40

40 35 0 2040 60 80 0 20 40 60 80 100 die size (mm2) die size (mm2)

Fig.36 QFP64 (14 × 14 × 2.7 mm). Fig.37 QFP64 (14 × 20 × 2.8 mm).

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Thermal design considerations Chapter 6

MBK341 MBK343 55 52 handbook, halfpage handbook, halfpage R th(j-a) Rth(j-a) (K/W) (K/W)

50 48

45 44

40 40

35 36 0 4080 120 0 4080 120 die size (mm2) die size (mm2)

Fig.38 QFP80 (14 × 20 × 2.8 mm). Fig.39 QFP100 (14 × 20 × 2.8 mm).

MBK340 MBK342 40 40 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

38 38

36 36

34 34

32 32 0 40 80120 160 0 40 80 120 160 die size (mm2) die size (mm2)

Fig.40 QFP120 (28 × 28 × 3.4 mm). Fig.41 QFP128 (28 × 28 × 3.4 mm).

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Thermal design considerations Chapter 6

MBK344 MBK345 38 80 handbook, halfpage handbook, halfpage Rth(j-a) R (K/W) th(j-a) (K/W) 36 70

34

60 32

30 50 0 4080 120 160 180 0 10 20 30 40 die size (mm2) die size (mm2)

Fig.42 QFP160 (28 × 28 × 3.4 mm). Fig.43 SDIP24 (400 mil).

MBK347 MBK349 75 70 handbook, halfpage handbook, halfpage R R th(j-a) th(j-a) (K/W) (K/W) 60 65

50

55 40

45 30 0 1020 30 40 0 2040 60 80 die size (mm2) die size (mm2)

Fig.44 SDIP32 (400 mil). Fig.45 SDIP42 (600 mil).

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Thermal design considerations Chapter 6

MBK346 MBK348 50 42 handbook, halfpage handbook, halfpage R th(j-a) R (K/W) th(j-a) (K/W) 45 38

40

34 35

30 30 0 40 80 120 0 20 40 6080 100 die size (mm2) die size (mm2)

Fig.46 SDIP52 (600 mil). Fig.47 SDIP64 (750 mil).

MBK350 MBK352 162 135 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

158 125

154 115

150 105 0 2468 10 0 210468 die size (mm2) die size (mm2)

Fig.48 SO8 (150 mil). Fig.49 SO14 (150 mil).

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Thermal design considerations Chapter 6

MBK354 MBK351 116 104 handbook, halfpage handbook, halfpage R Rth(j-a) th(j-a) (K/W) (K/W)

112 100

108 96

104 92

100 88 0 2104 6 8 0 51015 20 die size (mm2) die size (mm2)

Fig.50 SO16 (150 mil). Fig.51 SO16 (300 mil).

MBK353 MBK355 94 80 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

90 76

86 72

82 68 0 51015 20 0 10 20 30 die size (mm2) die size (mm2)

Fig.52 SO20 (300 mil). Fig.53 SO24 (300 mil).

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Thermal design considerations Chapter 6

MBK356 MBK358 74 68 handbook, halfpage handbook, halfpage R R th(j-a) th(j-a) (K/W) (K/W) 66 70

64

66 62

62 60 0 10 20 30 40 0 1020 30 40 die size (mm2) die size (mm2)

Fig.54 SO28 (300 mil). Fig.55 SO32 (300 mil).

MBK360 MBK357 160 160 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 155 155

150

150

145

145 140

140 135 0 2104 6 8 0 246 8 10 die size (mm2) die size (mm2)

Fig.56 SSOP14 (5.3 mm). Fig.57 SSOP16 (4.4 mm).

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Thermal design considerations Chapter 6

MBK359 MBK361 155 150 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

145 140

135 130

125 120 0 246 8 10 0 4812 die size (mm2) die size (mm2)

Fig.58 SSOP16 (5.3 mm). Fig.59 SSOP20 (4.4 mm).

MBK362 MBK364 140 130 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

130 120

120 110

110 100

100 90 0 24610 8 0 52010 15 die size (mm2) die size (mm2)

Fig.60 SSOP20 (5.3 mm). Fig.61 SSOP24 (5.3 mm).

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Thermal design considerations Chapter 6

MBK366 MBK365 120 84 handbook, halfpage handbook, halfpage R Rth(j-a) th(j-a) (K/W) (K/W) 83 110

82

100 81

90 80 0 52010 15 0 51510 die size (mm2) die size (mm2)

Fig.62 SSOP28 (5.3 mm). Fig.63 SSOP56 (7.5 mm).

MBK367 MBK368 75 75 handbook, halfpage handbook, halfpage R Rth(j-a) th(j-a) (K/W) (K/W) 70 70

65

65

60

60 55

55 50 0 20 4060 80 0 20 40 60 80 die size (mm2) die size (mm2)

Fig.64 TQFP44 (10 × 10 × 1 mm). Fig.65 TQFP64 (10 × 10 × 1 mm).

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Thermal design considerations Chapter 6

MBK370 MBK372 65 60 handbook, halfpage handbook, halfpage

Rth(j-a) Rth(j-a) (K/W) (K/W)

60 55

55 50

50 45 0 2040 60 80 0 2040 60 80 die size (mm2) die size (mm2)

Fig.66 TQFP80 (12 × 12 × 1 mm). Fig.67 TQFP100 (14 × 14 × 1 mm).

MBK369 MBK371 180 165 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 160

170 155

150 160

145

150 140 0 246 8 0 284 6 die size (mm2) die size (mm2)

Fig.68 TSSOP14 (4.4 mm). Fig.69 TSSOP16 (4.4 mm).

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Thermal design considerations Chapter 6

MBK373 MBK374 150 136 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W)

145 132

140 128

135 124

130 120 0 246 8 10 0 2468 10 die size (mm2) die size (mm2)

Fig.70 TSSOP20 (4.4 mm). Fig.71 TSSOP24 (4.4 mm).

MBK376 MBK378 130 106 handbook, halfpage handbook, halfpage Rth(j-a) Rth(j-a) (K/W) (K/W) 104 125

102

120 100

115 98 0 2104 6 8 0 4128 die size (mm2) die size (mm2)

Fig.72 TSSOP28 (4.4 mm). Fig.73 TSSOP48 (6.1 mm).

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Thermal design considerations Chapter 6

MBK375 MBK377 98 125 handbook, halfpage handbook, halfpage R th(j-a) R (K/W) th(j-a) (K/W) 96 120

94

115 92

90 110 0 4128 0 1020 30 40 die size (mm2) die size (mm2)

Fig.74 TSSOP56 (6.1 mm). Fig.75 VSO40 FeNi (7.5 mm).

MBK379 108 handbook, halfpage

Rth(j-a) (K/W)

104

100

96 0 10 2030 40 die size (mm2)

Fig.76 VSO56 FeNi (11 mm).

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Thermal design considerations Chapter 6

(1) THERMAL RESISTANCE (Rth(j-c)) DATA TABLES - POWER PACKAGES

PACKAGE NAME PHILIPS OUTLINE CODE Rth(j-c) (K/W) GLUED DIE Rth(j-c) (K/W) SOLDERED DIE DBS9MPF SOT111-1 6.0 to 12.0 n.a. DBS9P SOT157-2 1.0 to 4.0 0.8 to 3.0 DBS13P SOT141-6 1.0 to 4.0 0.8 to 3.0 DBS17P SOT243-1 1.0 to 4.0 0.8 to 3.0 DBS23P SOT411-1 n.a. 0.8 to 3.0 HSOP20 SOT418-2 1.0 to 4.0 0.8 to 3.0 RBS9MPF SOT352-1 6.0 to 12.0 n.a. RDBS13P SOT462-1 1.0 to 4.0 0.8 to 3.0 SIL9MPF SOT110-1 6.0 to 12.0 n.a. SIL9P SOT131-2 1.0 to 4.0 0.8 to 3.0 SIL13P SOT193-2 1.0 to 4.0 0.8 to 3.0

Note 1. a) Almost all of the values in the table were determined with measurements. b) Low values should be used with a large die, high values should be used with a small die.

April 2000 6 - 24