MCM12S10Q Delta Electronics, Inc., MCM12S10Q Datasheet - Page 14

• Manufacturer Part Number: MCM12S10Q
• Description: Integrated, Non-isolated, Point Of Load, Dc/dc Power Modules
• Manufacturer: Delta Electronics, Inc.

FEATURES DESCRIPTIONS (CON.)
Output Voltage Programming
The output voltage of the MCM12S10Q A can be
programmed to any voltage between 0.6Vdc and 2.5Vdc
by connecting one resistor (Please see reference
circuitry on page 2, R503) between the FB and PGND
pins of the module. Without this external resistor, the
output voltage of the module is 0.6 Vdc.
To calculate the value of the resistor Rtrim for a
particular output voltage Vo, please use the following
equation:
Rtrim is the external resistor in Ω
Vo is the desired output voltage
Table 1 shows the standard values of 1% R
for typical output voltages：
Table 1.
For example, to program the output voltage of the
MCM12S10Q A module to 1.8Vdc, Rtrim is calculated as
follows:
Rtrim = 4.88 kΩ
The amount of power delivered by the module is the
voltage at the output terminals multiplied by the output
current. When using the trim feature, the output voltage
of the module will be increased. At the same output
current level, it would increase the output power of the
module. Care should be taken to ensure that the
maximum output power of the module must not exceed
the maximum rated power (
R
R
DS_MCM12S10Q_07022008
Trim
Trim
R
Vout (V)
trim
=
=
0
(
0
kΩ
6 .
6 .
×
×
) Open 14.7 9.76 6.49 4.87 3.09
V
1
. 9
O
. 9
8 .
0.6
76
−
76
−
0
K
0
K
6 .
6 .
1.0
Vo.set x Io.max ≤ P max
1.2
1.5
1.8
trim
resistor
2.5
).
Output Capacitors
An output capacitor is required to filter the output and
supply
requirements are a function of the switching frequency
and the ripple current. The load transient requirements
are a function of the slew rate (di/dt) and the magnitude
of the transient load current. These requirements are
generally met with a mix of capacitors and careful
layout.
The bulk filter capacitor values are generally determined
by the ESR (effective series resistance) and voltage
rating
capacitance
decoupling capacitors should be placed as physically
close to the power pins of the load as possible.
The bulk capacitor’s ESR will determine the output
ripple voltage and the initial voltage drop after a high
slew-rate transient. An aluminum electrolytic capacitor's
ESR value is related to the case size with lower ESR
available in larger case sizes. In most cases, multiple
electrolytic capacitors of small case size perform better
than a single large case capacitor.
Additional output filtering may be required by the
system, if further reduction of output ripple or dynamic
transient spike is required.
requirements
the
load
requirements.
transient
rather
current.
than
High
by
The
the
frequency
filtering
actual
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