A.5 Conformal Coating

The areas around the 32 kHz real-time clock crystal oscillator have had the Dow Corning silicone-based 1-2620 conformal coating applied. The conformally coated area is shown in Figure A-5.The conformal coating protects these high-impedance circuits from the effects of moisture and contaminants over time.

Conformally coated

area

 

 

 

 

 

 

 

 

 

 

 

C12

 

 

R34

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J1

 

 

 

 

 

 

 

 

 

 

L5

C11

C14

 

C8

 

 

 

 

 

 

 

 

 

 

R20

 

 

L6

 

 

 

R1

 

 

 

 

 

 

 

 

 

L7

C9

C7

 

 

 

 

 

 

 

 

 

 

L4

 

C15

L3

 

R7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

R6

 

 

R2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

L2

 

 

R4

 

 

 

 

 

 

 

 

 

 

 

C16

 

C13

 

R5

R3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C10

R51

R8

 

 

 

 

 

 

 

 

 

 

 

 

L8

L9

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J2

 

 

 

 

C18T1

 

 

 

 

 

U1

ACT

 

DS1

 

 

C41 R35

 

 

 

Y1

 

C20

 

 

 

JP1

R9

 

R36

 

 

 

 

 

 

 

 

JP2

 

 

R10

 

R37

 

 

U6C34

 

C33

 

 

 

JP3

LINK

DS2

 

C47

U7

C42

R25

U5

R24

Q1

 

 

 

 

 

 

 

 

 

 

C43

C35

 

 

 

 

C24

 

 

 

 

 

 

 

 

 

C49C48

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C72

 

 

 

 

 

 

 

C25

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C26 C27

 

 

 

 

 

U3

 

 

C50

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Y3

C51

 

 

 

 

 

 

 

C28

 

 

 

 

 

 

C66

 

R47

C52

 

 

 

 

 

 

 

C29

 

 

 

 

 

 

 

C54

 

 

 

 

 

 

C32C31C30

 

 

 

 

 

 

R46

 

 

C53

 

 

 

 

 

 

 

 

 

 

 

 

U17

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

R48

 

C46 C45C44 R29

 

C36

 

 

 

 

 

 

 

 

 

C55C56

 

U9

 

 

U8

 

RP2

 

 

 

 

 

 

C71

 

Y2

 

 

R30

 

R26

 

 

 

 

 

 

 

 

 

R31

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C38

D1 R27

 

 

 

C22

 

 

 

 

 

 

R33 R32

 

 

 

R43

 

C23

 

 

 

 

 

 

JP4

 

R28

 

 

 

 

 

Figure A-5. RCM4000 Areas Receiving Conformal Coating

Any components in the conformally coated area may be replaced using standard soldering procedures for surface-mounted components. A new conformal coating should then be applied to offer continuing protection against the effects of moisture and contaminants.

NOTE: For more information on conformal coatings, refer to Technical Note 303, Con- formal Coatings.

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RabbitCore RCM4000

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Image 94
Digi RCM4000 user manual Conformal Coating, Conformally coated Area