STEVAL-ISA052V1 STMicroelectronics, STEVAL-ISA052V1 Datasheet - Page 25

• Manufacturer Part Number: STEVAL-ISA052V1
• Description: KIT EVAL PM6675S HE CTLR 2A REG
• Manufacturer: STMicroelectronics

Specifications of STEVAL-ISA052V1

• Main Purpose: DC/DC, Step Down with LDO
• Outputs And Type: 2, Non-Isolated
• Voltage - Output: 1.5V, 0.6 ~ 3.3V
• Current - Output: 10A, 2A
• Voltage - Input: 4.5 ~ 28 V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: PM6675
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-8426

PM6675S
Equation 7
where gm = 50 µs is the integrator trans conductance.
If the ripple on the COMP pin is greater than 150 mV, the auxiliary capacitor C
added. If q is the desired attenuation factor of the output ripple, C
Equation 8
In order to reduce the noise on the COMP pin, it is possible to add a resistor R
together with CINT and C
much greater (10 or more times) than the switching frequency:
Equation 9
If the ripple is very small (lower than approximately 20mV), a different compensation
network, called "Virtual-ESR" Network, is needed. This additional circuit generates a
triangular ripple that is added to the output voltage ripple at the input of the integrator. The
complete control scheme is shown in
FILT
, becomes a low pass filter. The cutoff frequency f
C
R
INT
INT
>
C
=
Figure 36
FILT
2
2
⋅ π
⋅ π
⎛
⎜
⎝
=
f
CUT
f
SW
C
k
g
INT
m
⋅
−
.
C
C
1
⋅
f
q
Zout
INT
1 (
INT
−
+
⎞
⎟
⎠
⋅
) q
C
C
⋅
FILT
Vout
FILT
Vr
FILT
is given by:
Device description
FILT
INT
CUT
that,
can be
must be
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