STEVAL-ISA051V2 STMicroelectronics, STEVAL-ISA051V2 Datasheet - Page 42

• Manufacturer Part Number: STEVAL-ISA051V2
• Description: BOARD EVAL PM6670AS DDR2/3
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA051V2

• Design Resources: STEVAL-ISA051V2 Gerber Files STEVAL-ISA051V2 Schematic STEVAL-ISA051V2 Bill of Material
• Main Purpose: Special Purpose DC/DC, DDR Memory Supply
• Outputs And Type: 4, Non-Isolated
• Voltage - Output: 1.5V, 1.8V
• Voltage - Input: 4.5 ~ 36V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: PM6670A
• Input Voltage: 4.5 V to 36 V
• Output Voltage: 1.8 V, 1.5 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: PM6670AS
• Kit Application Type: Power Management
• Application Sub Type: DDR2/3 Memory Power Supply Controller
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: PM6670AS
• Other names: 497-8412

Application information
8.1.3
42/53
It must be taken into account that in some MLCC the capacitance decreases when the
operating voltage is near the rated voltage. In
applications are listed.
Table 14.
Output capacitor selection
Using tantalum or electrolytic capacitors, the selection is made referring to ESR and voltage
rating rather than by a specific capacitance value.
The output capacitor has to satisfy the output voltage ripple requirements. At a given
switching frequency, small inductor values are useful to reduce the size of the choke but
increase the inductor current ripple. Thus, to reduce the output voltage ripple a low ESR
capacitor is required.
To reduce jitter noise between different switching regulators in the system, it is preferable to
work with an output voltage ripple greater than 25 mV.
As far as it concerning the load transient requirements, the Equivalent Series Resistance
(ESR) of the output capacitor must satisfy the following relationship:
Equation 36
where V
In addition, the ESR must be high enough high to meet stability requirements. The output
capacitor zero must be lower than the switching frequency:
Equation 37
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Manufacturer
TDK
RIPPLE
Evaluated MLCC for input filtering
is the maximum tolerable ripple voltage.
GMK325F106ZH-T
C3225X5R1E106M
GMK316F106ZL-T
GMK325BJ106KN
Series
Doc ID 14436 Rev 2
f
SW
Capacitance (μF) Rated voltage (V)
ESR
>
f
Z
≤
=
10
10
10
10
10
V
2
RIPPLE
⋅ π
Δ
Table 14
I
ESR
, L
MAX
1
,
MAX
⋅
C
some MLCC suitable for most of
out
35
35
25
50
35
Maximum Irms
@100 kHz (A)
2.2
2.2
2.5
PM6670AS
2