AN2521 Datasheet, PDF (31/33 Pages) STMicroelectronics – 19 V - 75 W laptop adapter with tracking boost PFC

AN2521
Transformer specification
Note:
Note:
8.4
Table 10. Winding characteristics
Pin
Winding
O/P RMS Number of
current
turns
5-6
3-1
Aux
Primary - A
0.05 A_RMS
0.39 A_RMS
7 spaced
60
8 - 10
19 V
5.2 A_RMS
8
4 - 2 Primary - B 0.39 A_RMS
60
All terminal wires must be insulated by tube
Figure 34. Winding position on coil former
Number of
layers
1
2
1
2
Wire type
G2 – φ 0.23 mm
G2 – 2 x φ 0.23 mm
Multistrand
G2 - 4 x φ 0.64 mm
G2- 2 x φ 0.23 mm
6.2
Polyester tape - 2 layers
Polyester tape - 2 layers
Polyester tape - 2 layers
Polyester tape - 1 layers
PRIMARY - B
19V
PRIMARY - A
AUX
6.2
Barrier tape
coil former
Primaries A & B are in parallel
Mechanical aspect and pin numbering
● Maximum height from PCB: 30 mm
● Coil former type: horizontal, 9+9 pins (pin 2 removed)
● pin distance: 4 mm
● Row distance: 35 mm
● External copper shield: not insulated, wound around the ferrite core and including the
coil former. Height is 12 mm.
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