Quasi-resonant CoolSET design guide
ICE2QRxx65/80x
Design Guide
21
8 August 2011
ICE2QR2280G: Vin=85Vac~265Vac
ICE2QR2280G: Vin=230Vac±15%
Figure 23 Input power curve for ICE2QR2280G
The major assumption for the calculation is listed below.
1.
Reflection voltage from secondary side to primary side is 115V for 650V CoolSET and 150V for 800V
CoolSET.
2.
The assumed maximum power for the device is when the junction temperature of the integrated
CoolMOS
®
reaches 125°C. (With some margins to reach the over temperature protection of the
device : 130°C). The maximum R
dson
of the device at 125°C is taken for calculation.
3.
For 650V DIP-8 CoolSET there is no copper area as heatsink and the R
thja
=90K/W, for 650V DIP-7
CoolSET there is no copper area as heatsink and the R
thja
=96K/W, for 650V DSO-12 CoolSET there
is no copper area as heatsink and the R
thja
=110K/W , for 800V DIP-7 CoolSET there is 232mm
2
copper area of 2oz PCB at drain pin for heatsink and the R
thja
=80K/W and for 800V DSO12 CoolSET
there is 232mm
2
copper area of 2oz PCB at drain pin for heatsink and the R
thja
=85K/W.
4.
Saturation current (I
d_max
@ 125°C) of the MOSFET is considered which is showed in below table.
5.
The typical resistance of the EMI filter is listed in the below table.
6.
The voltage drop for the bridge rectifier is assumed to be 1V.
Rdson_125°C (Ω)
I
d_max
@125°C (A)
R
EMI_filter
(Ω)
V
F_bridge
(V)
ICE2QR0665x
1.58
9.95
2 * 0.56
2 * 1
ICE2QR1065x
2.22
6.47
2 * 0.56
2 * 1
ICE2QR1765x
4.12
4.03
2 * 1
2 * 1
ICE2QR4765x
12.5
1.67
2 * 3
2 * 1
ICE2QR0680x
1.58
12.60
2 * 0.56
2 * 1
ICE2QR2280x
5.80
2.87
2 * 2
2 * 1
ICE2QR4780x
11.50
1.45
2 * 3
2 * 1
