1. Chapter 4 Components for Electronic Systems
Description of geometrical, thermal and some electrical properties of main types of components. No description of electrical properties of monolithic circuits.
Electronic Pack….. Chapter 4 Components for Electronic Systems

2. Hole Mounted Resistors
Mature design, fig. 4.1:
Carbon composite (a)
Metal film (b)
Wire wound (c)
Electronic Pack….. Chapter 4 Components for Electronic Systems

3. Surface Mounted Resistors
Fig.4.2.a: Thick film layers on ceramic substrate, rectangular shape
Electronic Pack….. Chapter 4 Components for Electronic Systems

4. Surface Mounted Resistors
Fig. 4.2 b): Metal system for termination on SMD resistors.
Electronic Pack….. Chapter 4 Components for Electronic Systems

5. Surface Mounted Resistors
Fig. 4.2 c): MELF-resistors have cylindrical body. (MELF is acronym for Metal Electrode Face Bonding)
Electronic Pack….. Chapter 4 Components for Electronic Systems

6. Surface Mounted Resistors
Table 4.1: Properties of SMD resistors
Electronic Pack….. Chapter 4 Components for Electronic Systems

7. Surface Mounted Resistors
Table 4.2: The resistance series E24, 12 and 6
Electronic Pack….. Chapter 4 Components for Electronic Systems

8. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors
In addition the capacitance, the following properties are important:
Maximum voltage rating
Temperature dependence of the capacitance (temperature coefficient)
Loss tangent (tan d), see below
Equivalent series resistance
Long term stability and ageing phenomena
High frequency properties
Leakage current
Ability to withstand various production processes (high temperature, etc.)
Price, physical size, etc.
Electronic Pack….. Chapter 4 Components for Electronic Systems

9. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
Main types:
Ceramic multilayer
Electrolytic dry, polarized
Electrolytic, wet, polarized
Metallized plastic film
Mica
Electronic Pack….. Chapter 4 Components for Electronic Systems

10. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
ELECTRICAL MODEL C = eo er x A /d /Z/ = [ Rs2 + (wL - 1/wC)2]1/2 Rs = series resistance (Rp neglected), L = inductance, fig Resonance for frequecy: wL = 1/wC Loss tangent: tan d = R / /Im Z/ = [Rp + Rs (1+ (wCRp)2) ] / ( wCRp2 - w L (1+ (wCRp)2) ]
Electronic Pack….. Chapter 4 Components for Electronic Systems

11. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
Fig.4.3: Electrical equivalent model for capacitor. If Rp can be neglected the impedance is given by:  Z  = [Rs2 + (wL - 1/wC)2]1/2
Fig. 4.4: The frequency dependence of impedance for multilayer ceramic capacitors (below) and tantalum electrolytic capacitors (top), all having 100 nF capacitance value.
Electronic Pack….. Chapter 4 Components for Electronic Systems

12. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
Fig. 4.5: Frequency dependence of the loss tangent tan d schematically. tan d = R / /Im Z/ = [Rp + Rs ( 1+ ( wCRp)2) ] / ( wCRp2 - w L (1+ ( wCRp)2) ]
Electronic Pack….. Chapter 4 Components for Electronic Systems

13. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
MULTILAYER CERAMIC CAPACITORS
Fig. 4.7.a: SMD Multilayer Ceramic Capacitor
Fig. 4.7.b: Metal system for the end
termination of multilayer ceramic capacitors.
Electronic Pack….. Chapter 4 Components for Electronic Systems

14. Multilayer Ceramic Capacitor, continued
Class 1: Low capacitance, good electrical properties, types NP0, N220, N750, COG, etc.
Class 2: High capacitance, poorer electrical behaviour, types X7R, Z5U
Fig. 4.8: Relative dielectric constant for ferroelectric ceramic
compositions (class 2), as a function of temperature, near the Curie point
Electronic Pack….. Chapter 4 Components for Electronic Systems

15. Multilayer Ceramic Capacitors, continued
Fig. 4.9: Properties of dielectrics of the types NP0, X7R and Z5U in SMD ceramic multilayer capacitors. Top: The voltage dependence of capacitance.
Middle: Loss tangent as function of temperature. Bottom: The temperature coefficient of the capacitance (Philips).
Electronic Pack….. Chapter 4 Components for Electronic Systems

16. Multilayer Ceramic Capacitors, continued
Fig. 4.10: Crack formation because of thermal stress in ceramic capacitors
Electronic Pack….. Chapter 4 Components for Electronic Systems

17. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
Tantalum, Dry Electrolytic
Very high capacitance, low voltages, low leakage current
Fig a): Tantalum SMD electrolytic capacitor (Philips), and hole mounted tantalum capacitors (Siemens)
Electronic Pack….. Chapter 4 Components for Electronic Systems

18. Electronic Pack….. Chapter 4 Components for Electronic Systems
Capacitors, continued
Tantalum, Dry Electrolytic
Fig b): Electrical properties of dry tantalum electrolytic capacitors (Philips).
Electronic Pack….. Chapter 4 Components for Electronic Systems

19. Wet Electrolytic Aluminium Capacitors
Fig a): Aluminium electrolytic capacitor for SMD mounting (Philips).
Electronic Pack….. Chapter 4 Components for Electronic Systems

20. Wet Electrolytic Aluminium Capacitors
Fig b): Aluminium electrolytic capacitor properties (Philips).
Top: Temperature dependence of the capacitance, relative to the value at 20 °C.
Middle: Temperature dependence of tan d.
Bottom: Temperature dependence of impedance at a frequency of 10 kHz.
Electronic Pack….. Chapter 4 Components for Electronic Systems

21. Diodes and transistors
Fig. 4.13: Axial, plastic encapsulated, hole mounted diodes to the left.
Centre: A plastic can with metal base for power diodes. It can be hole mounted or surface mounted, depending on how the leads are bent. The base is screwed to the substrate.
Right: A higher power diode in a metal can. Screw mounted to the substrate for efficient thermal contact.
Electronic Pack….. Chapter 4 Components for Electronic Systems

22. Diodes and transistors
Fig. 4.14: Various types of hole mounted transistor packages:
a) Left: Plastic packages, b) Centre: Low power metal packages
c) Right: Metal package for high power transistors. For the high power package, the collector is connected to the metal body.
Electronic Pack….. Chapter 4 Components for Electronic Systems

23. Diodes and transistors
Fig. 4.15: MELF-package for SMD diodes. The standard size is designated SOD-80, with dimensions shown to the right. (MELF: Metal Electrode Face Bonding)
Electronic Pack….. Chapter 4 Components for Electronic Systems

24. Diodes and transistors
Fig. 4.16: SOT-packages for SMD diodes and transistors: The most common, SOT-23 top left, SOT-89 for power transistors in the middle, and SOT-143 with four terminals to the right. The dimensions for SOT-23 are shown bottom left, and a cut-through SOT-89 in the middle. Ceramic SMD transistor packages with terminal placement like for SOT-23 are shown bottom right.
Electronic Pack….. Chapter 4 Components for Electronic Systems

25. Electronic Pack….. Chapter 4 Components for Electronic Systems
IC Packages
Plastic or Ceramic IC Packages?
Plastic:
Not hermetic
Low price in large quantities
High initial cost
Low thermal conductivity
Limited time at high temperature
Thermal mismatch to Si chip and metals
Not suitable for for high frequency circuits
Ceramic:
Hermetic, good reliability
Costly, but OK for prototyping
Good thermal conductivity
Low thermal coefficient of expansion, matches well with Si, mismatch to organic substrates
Gold metallization must be removed
Well defined high frequency properties
Electronic Pack….. Chapter 4 Components for Electronic Systems

26. Packages for hole mounted Ics
Fig. 4.17:a) DIP (Dual-in-line) IC package. b) Partly cross-sectioned DIP package which shows the silicon chip, bonding wires, lead frame and plastic body. c) The terminal organisation for 4 two-input NOR gates in a 14 pins package.
Electronic Pack….. Chapter 4 Components for Electronic Systems

27. Packages for hole mounted Ics
Fig. 4.18: Pin grid packages: To the left a cavity up ceramic package, and to the right a plastic moulded package.
Electronic Pack….. Chapter 4 Components for Electronic Systems

28. Electronic Pack….. Chapter 4 Components for Electronic Systems
SMD IC Packages
Small outline (SO)
Plastic leaded chip carrier (PLCC)
Leadless chip carrier (LLCC)
Leaded ceramic chip carrier
Flatpack, mini-flatpack
TapePak
Electronic Pack….. Chapter 4 Components for Electronic Systems

29. Electronic Pack….. Chapter 4 Components for Electronic Systems
SMD IC Packages
Fig. 4.19: Surface mounted SO (Small Outline) IC package (Philips).
Electronic Pack….. Chapter 4 Components for Electronic Systems

30. Electronic Pack….. Chapter 4 Components for Electronic Systems
SMD IC Packages
Table 4.3: Dimensions for SO- and VSO packages. Centre-to-centre lead distance is normally 50 mils, except for VSO-40 with 30 mils and VSO-56 with 0.75 mm
Electronic Pack….. Chapter 4 Components for Electronic Systems

31. SMD IC Packages: Plastic leaded chip carrier (PLCC)
Fig. 4.20: Plastic leaded chip carrier with (PLCC). They are normally square with an equal number of terminals on all four sides (top). For large DRAMs, the package has terminals on only two sides, also being called SOJ. The bottom figure shows a 1 or 4 Mbit DRAM package.
Electronic Pack….. Chapter 4 Components for Electronic Systems

32. SMD IC Packages: Plastic leaded chip carrier (PLCC)
Table 4.4 Dimensions for PLCC packages. Format means the number of terminals on two neighbouring sides.
Electronic Pack….. Chapter 4 Components for Electronic Systems

33. Leadless chip carrier (LLCC) Leaded ceramic chip carrier (LDCC)
Fig a): The various types of ceramic chip carriers [4.15]. Types A -D to the left are leadless (LLCC), whereas types A and B to the right are meant for mounting leads (LDCC).
Electronic Pack….. Chapter 4 Components for Electronic Systems

34. Leadless chip carrier (LLCC)
Fig b): LLCC packages, additional details. The longest terminal is to designate electrical terminal number 1 in the circuit.
Electronic Pack….. Chapter 4 Components for Electronic Systems

35. Leadless chip carrier (LLCC)
Table 4.5. LLCCs, dimensions.
Electronic Pack….. Chapter 4 Components for Electronic Systems

36. Leaded ceramic chip carrier (LDCC)
Fig. 4.22: Leaded ceramic chip carriers.
Electronic Pack….. Chapter 4 Components for Electronic Systems

37. Leaded ceramic chip carrier (LDCC)
Fig. 4.23: Various shapes of the leads, and leadless termination for comparison.
Electronic Pack….. Chapter 4 Components for Electronic Systems

38. Electronic Pack….. Chapter 4 Components for Electronic Systems
Flatpacks
Fig. 4.24: Quad flatpack with leads on all four sides. Flatpacks are usually made of plastic or ceramic. They have leads on four or two sides.
Electronic Pack….. Chapter 4 Components for Electronic Systems

39. Electronic Pack….. Chapter 4 Components for Electronic Systems
Mini-flatpacks
Fig. 4.25: Mini-flatpacks is a name for higher density flatpacks: Typically terminals and a pitch of 25 mils.
Electronic Pack….. Chapter 4 Components for Electronic Systems

40. Electronic Pack….. Chapter 4 Components for Electronic Systems
TapePak
Fig. 4.26: National Semiconductor´s TapePak component packages are specified with terminal numbers between 40 and close to 600. To the left we see a 40 leads TapePak in the form it is received by the user with a protective ring around it, and test points outside the ring. To the right is TapePak 40 after excising and lead bending, seen from above and from the side.
Electronic Pack….. Chapter 4 Components for Electronic Systems

41. High Performance Packages
Multilayer ceramic, Al2O3 or AlN
Ground planes
Controlled characteristic impedance
Thermal vias
Electronic Pack….. Chapter 4 Components for Electronic Systems

42. High Performance Packages
Fig. 4.27: Thermal via-holes in the printed circuit board, for better heat conduction.
Electronic Pack….. Chapter 4 Components for Electronic Systems

43. High Performance Packages
Fig. 4.28: Multilayer package for high frequency GaAs circuits with 3 ground planes, 2 voltage planes, 1 signal layer and a top conductor layer for contacts and sealing (Triquint).
Electronic Pack….. Chapter 4 Components for Electronic Systems

44. High Performance Packages
Fig. 4.29: Multichip package for memory module in a Hitachi high-performance computer [4.18]. The module contains 6 ECL chips, mounted by flip chip.
Electronic Pack….. Chapter 4 Components for Electronic Systems

45. Packages: Future trends
Fig. 4.30: Comparison between the size of various package forms for an integrated circuit with approximately 64 terminals.
Electronic Pack….. Chapter 4 Components for Electronic Systems

46. Packages: Future trends
Fig. 4.31: History and prognosis for the use of various sizes of passive SMD components, in percentage of the total number.
Electronic Pack….. Chapter 4 Components for Electronic Systems

47. Metallization of Terminals
Passives
Ag in alloy with Pd, Ni barrier, Sn/Pb
Ag in solder alloy
With adhesive mounting:
No Sn/Pb on terminal
ICs
Au removed
Sn/Pb coating
Electronic Pack….. Chapter 4 Components for Electronic Systems

48. Terminal metallisation, solderability and reliability
Fig. 4.32: Strain at fracture of solder fillet as function of gold concentration in the solder metal, relative to value without gold.
Electronic Pack….. Chapter 4 Components for Electronic Systems

49. Electrostatic Discharges (ESD)
Unprotected MOS: Max V on input before destroyed
Triboelectricity: >>1000 V discharge
Billions of $ damage annually
Protected circuits tolerate V
Extensive precautions in industry, handling and packing
Electronic Pack….. Chapter 4 Components for Electronic Systems

50. Electrostatic Discharges - Component Damages and Precautions
Fig. 4.33: MOS transistor schematically. The gate oxide is very vulnerable for damage by electrostatic discharge. Gate oxides down below 20Å are used.
Electronic Pack….. Chapter 4 Components for Electronic Systems

51. Electrostatic Discharges - Component Damages and Precautions
Fig. 4.34: CMOS circuit exposed to electrostatic damage: Silicon has molten in a small area. Picture size  5m x 5m.
Electronic Pack….. Chapter 4 Components for Electronic Systems

52. Electrostatic Discharges - Component Damages and Precautions
Fig. 4.35: ESD protection circuit at in- and outputs for MOS and for bipolar circuits.
Electronic Pack….. Chapter 4 Components for Electronic Systems

53. Electronic Pack….. Chapter 4 Components for Electronic Systems
Component Packaging
Paper tape (hole mounted passives)
Blister tape (SMD passives, discretes, small ICs)
Sticks (DIPs, SMD ICs)
Waffle trays (Flatpacks)
Stack magazine
Bulk: Not suited for automatic mounting
Electronic Pack….. Chapter 4 Components for Electronic Systems

54. Component Packaging for Automatic Placement
Fig. 4.36: Blister tape for surface mounted components. Standard dimensions for 8 mm wide tape.
Electronic Pack….. Chapter 4 Components for Electronic Systems

55. Component Packaging for Automatic Placement
Fig. 4.37: Plastic sticks as packaging for SMD integrated circuits.
Electronic Pack….. Chapter 4 Components for Electronic Systems

56. Component Packaging for Automatic Placement
Fig. 4.38: Waffle trays packaging for flatpacks to the left, frame for stacking of single component to the right.
Electronic Pack….. Chapter 4 Components for Electronic Systems

57. Chapter 4 Components for Electronic Systems
End of overhead series from Chapter 4
Electronic Pack….. Chapter 4 Components for Electronic Systems