SC600
POWER MANAGEMENT
Applications Information (Cont.)
where:
Short-Circuit and Over-Temperature Protection
VO = output voltage
IO = output currrent
mode = 1.5x or 2x
VIN = input voltage
IQ = quiescent current
The output current is limited to 600mA to protect against
short-circuit conditions. Over-temperature protection is
also provided.
Design and Layout Considerations
(from Electrical Characteristics on page 2)
The layout example on page 15 uses the 1206 case size
for the capacitors, so a smaller layout area is possible.
The mode may be identified by measuring input current The bucket capacitors and the SC600 are on the same
and output current and calculating as mode = IIN/IOUT side of the card. To minimize trace inductance, traces are
.
Alternately, the mode can be identified by identifying short and wide with no vias to the bucket capacitors. The
the voltage at the bucket capacitor, CF1 with an input and output caps are on the bottom side directly un-
oscilloscope.
der the SC600 and vias are used to connect directly to
copper shapes used for the input and output. The input
and output capacitors and Pin 8 should be connected to
ground very near the SC600.
Calculating Power Dissipation
The power dissipated by the SC600 is calculated as,
PD = PIN - POUT
PD = VIN · (mode IO + IQ) - VO · IO
Suggested Capacitors
The following is a short list of some of the manufacturers
and types of multi-layer ceramic capacitors that are sug-
gested for the SC600.
Manufacturer
Part Number
Capacitance[μF] Dielectric Type EIA Package Size
Voltage
Rating
AVX
AVX
0805ZC225K
0805ZC105K
2.2
1.0
X7R
X7R
X7R
X5R
X7R
X5R
X5R
X5R
X5R
X5R
0805
0805
0805
0805
0805
0402
0603
0603
0805
0603
10V
10V
10V
6.3V
10V
6.3V
6.3V
10V
10V
AVX
0805ZC334K
0.33
2.2
Panasonic
Panasonic
Panasonic
Panasonic
TDK
ECJ2YB0J225K
ECJ2YB1A105
ECJ1VB0J105K
ECJ1VB0J334K
C1608X5R1A105
C1202Y5V1A106Z
C1608X5R1A334k
1.0
1.0
0.33
1.0
TDK
1.0
TDK
0.33
10V
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12
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