PI354X-00 Datasheet, PDF (34/39 Pages) –

PI354x-00
Device
V_IN
(V)
I_LOAD
(A)
C_INPUT
Ceramic
X7R
C_OUTPUT
Ceramic
X7R
PI3542-00
48
10
5
5 x 2.2µF
100V
6 x 100µF
PI3543-00
48
10
5
5 x 2.2µF
100V
6 x 100µF
PI3545-00
48
10
5 x 2.2µF
5
100V
6 x 47µF
PI3546-00
48
9
5 x 2.2µF
4.5
100V
6 x 10µF
Table 3 — Recommended input and output capacitance
C_INPUT
Ripple
Current
(A_RMS)
0.7
0.8
.88
1.12
C_OUTPUT
Ripple
Current
(A_RMS)
1.32
Input
Ripple
(mVpp)
416
220
464
1.3
230
485
1.37
245
880
1.26
125
Output
Ripple
(mVpp)
Transient
Deviation
(mVpk)
Recovery
Time
(µs)
Load
Step
(A)
(Slew/µs)
47
22
±80
40
5
(1A/µs)
61.6
±90
31
40
5
(1A/µs)
62
32
±150
40
5
(1A/µs)
114
±300
33
20
5
(1A/µs)
Murata Part Number
Description
GRM32ER72A225KA35
2.2µF 100V 1210 X7R
GRM32EC70J107ME15
100µF 6.3V 1210 X7S:EIA
GRM32ER71A476KE15
47µF 10V 1210 X7R:EIA
GRM32ER61H106MA12
10µF 50V 1210 X5:EIA
Table 4 — Capacitor manufacturer part numbers
Layout Guidelines
To optimize maximum efficiency and low noise performance
from a PI354x-00 design, layout considerations are necessary.
Reducing trace resistance and minimizing high current loop
returns along with proper component placement will contribute
to optimized performance.
A typical buck converter circuit is shown in Figure 68. The
potential areas of high parasitic inductance and resistance are the
circuit return paths, shown as LR below.
V_IN
C_IN
C_OUT
V_IN
C_IN
C_OUT
Figure 69 — Current flow: Q1 closed
When Q1 is on and Q2 is off, the majority of C_IN’s current is used
to satisfy the output load and to recharge the C_OUT capacitors.
When Q1 is off and Q2 is on, the load current is supplied by the
inductor and the C_OUT capacitor as shown in Figure 70. During
this period C_IN is also being recharged by the V_IN. Minimizing C_IN
loop inductance is important to reduce peak voltage excursions
when Q1 turns off. Also, the difference in area between the C_IN
loop and C_OUT loop is vital to minimize switching and GND noise.
Figure 68 — Typical Buck Regulator
The path between the C_OUT and C_IN capacitors is of particular
importance since the AC currents are flowing through both of
them when Q1 is turned on. Figure 69, schematically, shows the
reduced trace length between input and output capacitors. The
shorter path lessens the effects that copper trace parasitics can
have on the PI354x-00 performance.
Cool-Power^® ZVS Switching Regulators
Page 34 of 39
Rev 1.6
03/2017
V_IN
C_IN
C_OUT
Figure 70 — Current flow: Q2 closed
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