STEVAL-ISA050V1 STMicroelectronics, STEVAL-ISA050V1 Datasheet - Page 27

• Manufacturer Part Number: STEVAL-ISA050V1
• Description: KIT EVAL PM6641 CHIPSET/DDR2/3
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA050V1

• Main Purpose: Special Purpose DC/DC, DDR Memory Supply
• Outputs And Type: 4, Non-Isolated
• Power - Output: 14.7W
• Voltage - Output: 1.05V, 1.5V, 1.8V, 0.9V
• Current - Output: 4A, 2.8A, 2.5A, 2A
• Voltage - Input: 2.7 ~ 5.5V
• Regulator Topology: Buck
• Frequency - Switching: 750kHz
• Board Type: Fully Populated
• Utilized Ic / Part: PM6641
• Input Voltage: 2.7 V to 5.5 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: PM6641
• Kit Application Type: Power Management - Voltage Regulator
• Application Sub Type: Monolithic Voltage Regulator
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PM6641
• Other names: 497-8425

PM6641
7.5
Output voltage divider
PM6641 switching regulators are adjustable voltage converters.
If the feedback pin (VFB_1S8, VFB_1S5, VFB_1S05 respectively belonging to
VDDQ (1.8 V), 1.5 V, 1.05 V rail) is directly tied to the rail output capacitor the internal divider
with pre-fixed output voltage value is activated and the nominal output voltages are
selected.
If the feedback pin is connected to the output voltage divider central tap (as depicted in
Figure 30
Figure 30. SW regulator with external divider
the PM6641 switching regulator automatically recognizes the external divider and the output
voltage is regulated to the following value:
Equation 5
)
Doc ID 13510 Rev 3
Vout
R
R
1
2
_
1
Sxx
=
⎛
⎜ ⎜
⎝
VFB_1Sxx
Vout_1Sxx
R
R
2
1
+
1
⎞
⋅ ⎟ ⎟
⎠
0
8 .
V
Device description
27/47