User Manual

CDB1610-8W
DS977DB4 13
6.2 Flyback Transformer
The flyback transformer stage is a quasi-resonant current-regulated DC-DC Converter capable of delivering the
highest possible efficiency at a constant current while minimizing line frequency ripple. The auxiliary winding is used
for zero-current detection and overvoltage protection.
Figure 8. Flyback Transformer Schematic
6.2.1 Electrical Specifications
Characteristics conditions:
• Operating temperature range: -25 °C to +120 °C (including coil heat)
Notes: 8. Time = 2sec.
9. Measured across pins 3 and 4.
10. Measured across pins B and A.
11. Measured across pins 2 and 1.
Parameter Condition Sym Min Typ Max Unit
Flyback Transformer
Electrical Strength (Note 8)
f
operate
=50/60Hz
-4K-V
RMS
Primary Inductance (Note 9)
f
resonant
=10kHz, 0.3V at
20°C
L
P
2.79 3.1 3.41
mH
Primary Leakage Inductance (Note 9)
f
resonant
=10kHz, 0.3V at
20°C
L
K
-
-
15
H
Primary DC Resistance (Note 9)
t
DCR
=20°C
2.175 2.90 3.625

Secondary DC Resistance (Note 10)
t
DCR
=20°C
-
-
0.22 
Auxiliary DC Resistance (Note 11)
t
DCR
=20°C
0.3975 0.53 0.6625 
113T
#36 AWG
(0.13mm)
67 T
# 36AWG
(0.13mm)
10 T
# 36AWG
(0.13mm)
Primary
4
5
3
1
Auxiliary
2
Secondary
10T
#27AWG
(0.35mm)
B
A