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NTC Chip Thermistor Soldering and Mounting
2018/03/27 09:03:03
1. Mounting Position
  Choose a mounting position that minimzes the stress imposed on the chip during flexing or
  bending of the board.
     
2. Allowable Soldering Temperature and Time
  2-1 Solder within the temperature and time combinations, indicated by the slanted lines
        in the following graphs.
  2-2 The excessive soldering conditions may cause dissolution of metallization or
        deterioration  of solder-wetting  on the external electrode.
  2-3 In case of repeated soldering the accumulated soldering time should be within the
       range shown below figure.( For example, Reflow peak temperature :260℃, twice ->
     The total accumulated soldering time at 260℃ is within 30 seconds.)
     
     
    
 
3. Recommendable Temperature Profile for Soldering
 3-1 Insufficient preheating may cause a crack on ceramic body. The difference between
       preheating temperature  and maximum temperature in the profile shall be 100C
 3-2 Rapid cooling by dipping in solvent or by other means is not recommended.
*In case of repeated soldering, the accumulated soldering time should be within the range
 shown above figure 2
  
 
4. Solder and Flux
 4-1 Solder and paste
    A) Reflow soldering: CT0201/0402/0603/0805 series
       Use RA/RMA type or equivalent type of solder paste.
    
    B)Flow Soldering: NCP0603/0805 series
      We are using the solder paste below for any internal tests of this product.
      Sn:Pb=63WT%:37%
       Sn:Ag:Cu=96.5wt%:3.0wt%:0.5wt%
 
 4-2 Flux
Use rosin type flux in soldering process. If below flux is used, some problems might
be caused in the product characteristics and reliability. Please do not use below flux.
   *Strong acidic flux(with halide content exceeding 0.1wt%)
   *Water-soluble flux
(Water-soluble flux can be defined as non rosin type flux including wash-type flux and   non-wash-type flux)
 
5. Cleaning  Conditions
   For removing the flux after soldering, observe the following points in order to avoid deterioration
of characteristics or any change of the external electrodes' quality.
  *Please keep mounted parts and a substrate from an occurrence of resonance in ultrasonic cleaning.
  *Please do not clean the products in the case of using a non-washed type flux.
 
  CT0201/0402 CT0603/0805
Solvent Isopropyl alcohol Isopropyl alcohol
Dipping Cleaning Less than 5 minutes at room temp. Or less than 2 minutes at  40℃ max. Less than 5 minutes at room temp. Or less than 2 minutes at  40℃ max.
Ultrasonic Cleaning Less than 5 minutes and 20W/ℓ, Frequency of 28 to 40KHZ Less than 5 minutes and 20W/ℓ, Frequency of several 10kHz to 100kHz
6. Drying
   After cleaning, promptly dry this product.
 
7. Printing Conditions of Solder Paste
7-1 The amount of solder of critical. Standard height of fillet is shown in the table below.
7-2 Too much soldering may cause mechanical stress, resulting in cracking, mechanical and/or electronic damage.
 
Part No. The solder paste Thickness               T
CT0201 100um 1/3E ≤ T  ≤ E
CT0402 150um 1/3E ≤ T  ≤ E
CT0603/0805 200um 0.2mm ≤ T  ≤ E
8. Adhesive Application and Curing
 8-1 Thin or insufficient adhesive may result in loose component contact with land during flow soldering.
 8-2 Low viscosity adhesive causes chips to slip after mounting.
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