STEVAL-ISA051V2 STMicroelectronics, STEVAL-ISA051V2 Datasheet - Page 47

• 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

PM6670AS
8.1.7
All ceramic capacitors application
Design of external feedback network depends on the output voltage ripple across the output
capacitors' ESR. If the ripple is great enough (at least 20 mV), the compensation network
simply consists of a C
Figure 40. Integrative compensation
The stability of the system depends firstly on the output capacitor zero frequency. It must be
verified that:
Equation 48
where k is a free design parameter greater than unity (k > 3). It determines the minimum
integrator capacitor value C
Equation 49
COMP
C
FILT
R
INT
INT
VREF
capacitor.
INT
Doc ID 14436 Rev 2
:
C
Integrator
C
f
INT
SW
Ton One-shot
INT
generator
>
>
Comparator
+
-
2
k
⋅ π
⋅
PWM
f
Zout
⎛
⎜
⎝
g
f
m
SW
k
g
=
+
m
-
−
2
⋅ π
f
Zout
R
k
out
⎞
⎟
⎠
Vr=0.9
⋅
C
Vref
Vo
out
Application information
VSNS
VDDQ
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