AN2485 datasheet(19/29 Pages) STMICROELECTRONICS

Part #	AN2485

Description	400 W FOT-controlled PFC pre-regulator with the L6563

PDF	29 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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19 / 29 page

AN2485

Layout hints

19/29

This point is the RTN star point. A downstream converter must be connected to this

return point.

Minimize the length of the traces relevant to L3, boost inductor L4, boost rectifier D4

and output capacitor C6 and C7.

Keep signal components as close as possible to L6563 pins. Keep the tracks relevant

to the pin #1 (INV) net as short as possible. Components and traces relevant to the

Error Amplifier must be placed far from traces and connections carrying signals with

high dv/dt like Mosfet Drains (Q1 and Q2).

Connect heat sinks to Power GND.

Add an external shield to the boost inductor and connect it to Power GND.

Connect the RTN of signal components including the feedback, PFC_OK and MULT

dividers close to the L6563 pin #12 (GND).

Connect a ceramic capacitor (100÷470 nf) to pin #14 (Vcc) and to pin #12 (GND), close

to the L6563 connect this point to the RTN star point (see point 1.).

Figure 34.

EVAL6563-400W PCB layout (not 1:1 scaled)

AN2485 Datasheet(PDF) 19 Page - STMicroelectronics