STODD01 STMicroelectronics, STODD01 Datasheet - Page 21

• Manufacturer Part Number: STODD01
• Description: Monolithic power management for high definition ODD with true shut-down, reset, and programmable step-up voltage
• Manufacturer: STMicroelectronics

Specifications of STODD01

• Typical Efficiency: > 90 %
• Low Switching Quiescent Current: max 2.2 mA overtemperature range

STODD01
9
9.1
9.2
9.3
Application information
Introduction
The following is some technical information for estimating the typical external components
characteristics using standard literature equations. Nevertheless, it is strongly
recommended to validate the external components suitability to the application
requirements, thoroughly testing any solution at bench level on a real evaluation circuit.
Programming the output voltage
The output voltage for the step-up (ch1) can be adjusted from 6.5 V up to 14 V by
connecting a resistor divider between the V
divider must be connected to the FB1 pin, as shown in
The resistor divider should be chosen in accordance with the following equation:
Equation 1
It is recommended to use a resistor with a value in the range of 1 kΩ to 50 kΩ. Lower values
can also be suitable, but increase current consumption.
For ch2 the device integrates the resistor divider needed to set the correct output voltage.
This allows 2 external components to be saved. The FB2 pin must be connected directly to
V
The output voltage for Ch3 can be adjusted from 0.8 V up to 85 % of the input voltage value
by connecting a resistor divider between V
must be connected to FB3 pin, as shown in
The resistor divider must be chosen according to the following equation:
Equation 2
Using a resistor with a value in the range of 1 kΩ to 50 kΩ is recommended. Lower values
are also suitable, but increase current consumption.
Inductor selection
The inductor is the key passive component for switching converters.
The inductor selection must take the boundary conditions in which the converter works into
consideration, the maximum input voltage for the buck and the minimum input voltage for the
boost.
V
V
OUT2
OUT
OUT
1
3
.
=
=
V
V
FB
FB
1
3
×
×
⎛
⎜
⎝
⎛
⎜
⎝
1
1
+
+
R
R
R
R
2
1
3
4
⎞
⎟
⎠
⎞
⎟
⎠
Doc ID 17789 Rev 2
OUT3
OUT1
Figure
and GND, the middle point of the divider
and the GND, the middle point of the
3.
Figure
3.
Application information
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