STEVAL-ISA052V2 STMicroelectronics, STEVAL-ISA052V2 Datasheet - Page 32

• Manufacturer Part Number: STEVAL-ISA052V2
• Description: BOARD EVAL BASED ON PM6675A
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA052V2

• Design Resources: STEVAL-ISA052V2 Gerber Files STEVAL-ISA052V2 Schematic STEVAL-ISA052V2 Bill of Material
• Main Purpose: DC/DC, Step Down with LDO
• Outputs And Type: 2, Non-Isolated
• Voltage - Output: 1.5V, 0.6 ~ 3.3V
• Voltage - Input: 4.5 ~ 36 V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: PM6675AS
• Input Voltage: 4.5 V to 36 V
• Output Voltage: 1.5 V
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed
• For Use With/related Products: PM6675AS
• Other names: 497-8413

Device description
7.2.1
32/48
Figure 34. LDO output voltage selection
A compensation capacitor Cc must be added to adjust the dynamic response of the loop.
The value of Cc is calculated according to the desired bandwidth of the LDO regulator and
depends on the value of the feedback resistors. In most of applications the pole due to the
compensation capacitor is placed at 100-200 kHz (equation 24).
Equation 24
The LIN input can be connected to the switching section output for compact solutions or to a
lower supply, if available in the system, in order to reduce the power dissipation of the LDO.
A minimum output capacitance of 20 µF (2x10 µF MLCC capacitors) is enough to assure
stability and fast load transient response.
LDO section current limit
The LDO regulator can handle up to ±2 Apk, depending on the LDO input voltage and the
LILIM pin setting. The output current is limited to ±1 A or ±2 A if the LILIM pin is connected
to SGND or AVCC respectively (
Figure 35. LDO current limit setting
The maximum current that the LDO can source depends also on the input and output
voltages. Due to the high side MOSFET of the output stage, the LDO cannot source the limit
current at high output voltages.
source as function of the input and output voltages. For output voltages higher than 2 V, the
maximum output current is limited as reported.
V
LOUT
±2A CL
±1A CL
C
OUT
f
p
=
Figure 36
+5V
Figure 35
2
Cc
π
R (
19
⊕
R20
shows the maximum current that the LDO can
).
R19
1
R
20
LILIM
)
⋅
PM6675AS
C
LOUT
LFB
LGND
C
PM6675AS
=
200
kHz
PM6675AS