Datasheet

CoolSET
®
-F3
ICE3A1065ELJ
Schematic for recommended PCB layout
Version 2.3 27 19 Nov 2012
8 Schematic for recommended PCB layout
C11
bulk cap
R11
D11
C12
IC12
R12
C13
C16
C15
C14
D13
R14
R23
R22
IC21
C23
R24
C22
R21
R25
GND
Vo
D21
C21
F3 CoolSET schematic for recommended PCB layout
R13
Z11
TR1
N
L
BR1
C2
Y-CAP
C3
Y-CAP
C1
X-CAP
L1
FUSE1
C4
Y-CAP
GND
Spark Gap 3
Spark Gap 4
D11
Spark Gap 1
Spark Gap 2
FB
CS
GND NC
SOFTS
VCC
F3
DRAIN
CoolSET
IC11
Figure 32 Schematic for recommended PCB layout
General guideline for PCB layout design using F3 CoolSET
®
(refer to Figure 32):
1. “Star Ground “at bulk capacitor ground, C11:
“Star Ground “means all primary DC grounds should be connected to the ground of bulk capacitor C11
separa
tely in one point. It can reduce the switching noise going into the sensitive pins of the CoolSET
®
device
effectively. The primary DC grounds include the followings.
a. DC ground of the primary auxiliary winding in power transformer, TR1, and ground of C16 and Z11.
b. DC ground of the current sense resistor, R12
c. DC ground of the CoolSET
®
device, GND pin of IC11; the signal grounds from C13, C14, C15 and collector
of IC12 should be connected to the GND pin of IC11 and then “star “connect to the bulk capacitor ground.
d. DC ground from bridge rectifier, BR1
e. DC ground from the bridging Y-capacitor, C4
2. High voltage traces clearance:
High voltage traces should keep enough spacing to the n
earby traces. Otherwise, arcing would incur.
a. 400V traces (positive rail of bulk capacit
or C11) to nearby trace: > 2.0mm
b. 600V traces (drain voltage of CoolSET
®
IC11) to nearby trace: > 2.5mm
3. Filter capacitor close to the controller ground:
Filter capacitors, C13, C14 and C15 should be placed as
close to the controller ground and the controller pin
as possible so as to reduce the switching noise coupled into the controller.
Guideline for PCB layout design when >3KV lightning surge test applied (refer to Figure 32):
1. Add spark gap
Spark gap is a pair of saw-tooth like copper plate f
acing each other which can discharge the accumulated
charge during surge test through the sharp point of the saw-tooth plate.
a. Spark Gap 3 and Spark Gap 4, input common mode choke, L1:
Gap separation is around 1.5mm (no safety concern)