SC2612E
POWER MANAGEMENT
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 SC2612E 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 SC2612E should be supplied from the 5V
supply through a 10Ω resistor, the Vcc pin should be
decoupled directly to AGND by a 0.1µF ceramic capaci-
tor, trace lengths should be as short as possible.
Vin
Currents in Power Section
+
Vout
+
2004 Semtech Corp.
9
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