Surface Mounting Guide
MLC Chip Capacitors
SOLDER PAD DESIGN
Case Size
D2
0805
1206
1210
*1808
*1812
*1825
*2220
*2225
*HQCC
*3640
*HQCE
3.00
4.00
4.00
5.60
5.60
5.60
6.60
6.60
6.60
10.67
10.67
millimeters (inches)
D2
D3
1.00
2.00
2.00
3.60
3.60
3.60
4.60
4.60
4.60
7.62
7.62
(0.040)
(0.090)
(0.090)
(0.140)
(0.140)
(0.140)
(0.180)
(0.180)
(0.180)
(0.300)
(0.300)
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.52
1.52
D1
(0.120)
(0.160)
(0.160)
(0.220)
(0.220)
(0.220)
(0.260)
(0.260)
(0.260)
(0.427)
(0.427)
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.52
1.52
D4
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.060)
(0.060)
D5
1.25
1.60
2.50
2.00
3.00
6.35
5.00
6.35
6.35
10.16
10.16
(0.050)
(0.060)
(0.100)
(0.080)
(0.120)
(0.250)
(0.200)
(0.250)
(0.250)
(0.400)
(0.400)
D1
D3
D4
D5
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.040)
(0.060)
(0.060)
*AVX recommends reflow soldering only.
Component Pad Design
Component pads should be designed to achieve good
solder filets and minimize component movement during
reflow soldering. Pad designs are given for the most common
sizes of multilayer ceramic capacitors for both wave and
reflow soldering. The basis of these designs is:
• Pad width equal to component width. It is permissible to
decrease this to as low as 85% of component width but it
is not advisable to go below this.
• Pad overlap 0.5mm beneath component.
• Pad extension 0.5mm beyond components for reflow and
1.0mm for wave soldering.
Preheat & Soldering
The rate of preheat should not exceed 4°C/second to
prevent thermal shock. A better maximum figure is about
2°C/second.
For capacitors size 1206 and below, with a maximum
thickness of 1.25mm, it is generally permissible to allow a
temperature differential from preheat to soldering of 150°C.
In all other cases this differential should not exceed 100°C.
For further specific application or process advice, please
consult AVX.
Cleaning
Component Spacing
For wave soldering components, must be spaced sufficiently
far apart to avoid bridging or shadowing (inability of solder to
penetrate properly into small spaces). This is less important
for reflow soldering but sufficient space must be allowed to
enable rework should it be required.
≥1.5mm
(0.06)
≥1mm
(0.04)
Care should be taken to ensure that the capacitors are
thoroughly cleaned of flux residues especially the space
beneath the capacitor. Such residues may otherwise
become conductive and effectively offer a low resistance
bypass to the capacitor.
Ultrasonic cleaning is permissible, the recommended
conditions being 8 Watts/litre at 20-45 kHz, with a process
cycle of 2 minutes vapor rinse, 2 minutes immersion in the
ultrasonic solvent bath and finally 2 minutes vapor rinse.
≥1mm
(0.04)
65
AVX [ AVX CORPORATION ]
