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POWER MANAGEMENT

SC2612A/C

Layout Guidelines (Cont.)

4) The Output Capacitor(s) (Cout) should be located as

close to the load as possible, fast transient load cur-

rents are supplied by Cout only, and connections between

Cout and the load must be short, wide copper areas to

minimize inductance and resistance.

5) The SC2612 is best placed over a quiet ground plane

area, avoid pulse currents in the Cin, Q1, Q2 loop flowing

in this area. PGNDH and PGNDL should be returned to

the ground plane close to the package. The AGND pin

should be connected to the ground side of (one of) the

output capacitor(s). If this is not possible, the AGND pin

may be connected to the ground path between the Out-

put Capacitor(s) and the Cin, Q1, Q2 loop. Under no cir-

cumstances should AGND be returned to a ground in-

side the Cin, Q1, Q2 loop.

6) Vcc for the SC2612 should be supplied from the 5V

supply through a 10

Ω resistor, the Vcc pin should be

decoupled directly to AGND by a 0.1

µF ceramic capaci-

tor, trace lengths should be as short as possible.

Vout

Vin

+

+

Currents in Power Section