Murata Posistor PRG21BC MM1RK Series Manual page 5

5. Solder and Flux
(1) Solder Paste
Use solder paste with Sn:Pb=60:40wt% , Sn:Pb=63:37wt% ,Sn:Ag:Cu = 96.5:3.0:0.5wt%
Use of the solder containing Zn may reduce adhesive strength. When you use the solder containing
Zn, please contact us in advance.
For your reference, we are using
'63Sn/37Pb RMA9086 90-3-M18', manufactured by Alpha Metals Japan Ltd.,
'96.5Sn/3.0Ag/0.5Cu M705-GRN360-K2-V', manufactured by Senju Metal Industry Co., LTD
for any Internal tests of this product.
(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 0.2wt%).
• Water-soluble flux(*Water-soluble flux can be defined as non rosin type flux including wash-type flux
and non-wash-type flux.)
6. For removing the flux after soldering, observe the following points in order to avoid deterioration of the
characteristics or any change of the external electrodes quality.
(1) Cleaning Conditions
Solvent Dipping Cleaning
Less than 5 min.
2-propanol
Less than 2 min.
*A sufficient cleaning shall be applied to remove flux
* 2-propanol is recommended as cleaning solvent. Please contact us in case you use other
cleaning solvent.
*Do not use "Pine alpha SR100S"&"Clean through 750L" for removing the flux after
soldering. Because they may deteriorate PTC element.
(2) Drying : After cleaning, dry promptly this product.
7. In your mounting process, observe the following points in order to avoid deterioration of the
characteristics or destruction of this product. The mounting quality of this product may also be affected by
the mounting conditions, shown the points below.
This product is for only reflow soldering. Flow soldering shall not be allowed.
Please mount this product by soldering. When mounted by other methods, such as conductive adhesives,
please contact us in advance.
(1) Standard Land Size
Too big land size gives too much solder paste on the land. It may cause destruction of this product,
because of the mechanical stress especially in the case of board bending.
a
(2) Printing Conditions of Solder Paste
i. Standard thickness of solder paste printing shall be from 0.15 to 0.20 mm.
ii. After soldering, the solder fillet shall be a height from 0.2 mm to the thickness of this product.
(See the figures below.)
iii. Too much solder gives too strong mechanical stress to this product, such stress may cause
cracking or any mechanical damage. And also, it can destroy the electrical performance of this
product.
This information may be changed without a previous notice.
at room temp.
or
Frequency of several 10 kHz
at 40°C max.
b
c
1.0~1.2
Murata Manufacturing Co., Ltd.
Ultrasonic Cleaning
Less than 1 min.
20W/L max.
to 100 kHz.
a b
0.5~0.7
c
1.0~1.2
(mm)
CE-025Q