Output Voltage Calculation

flux

The output voltage for a buck converter using a resistor divider is given by:
Vout=VFB(1+R1R2)\Large V_{\text{out}} = V_{\text{FB}}\left(1 + \frac{R_1}{R_2}\right)
For the TPS5430DDA, the typical feedback reference voltage, ( V_{\text{FB}} ), is 0.8 V.
With the resistor values provided:
  • ( R_1 = 33,kΩ )
  • ( R_2 = 10,kΩ )
the calculation is:
Vout=0.8 V(1+33 kΩ10 kΩ)=0.8 V×(1+3.3)=0.8 V×4.3=3.44 V\Large V_{\text{out}} = 0.8\,V \left(1 + \frac{33\,kΩ}{10\,kΩ}\right) = 0.8\,V \times (1 + 3.3) = 0.8\,V \times 4.3 = 3.44\,V
Thus, using the current resistor divider, the output voltage is approximately 3.44 V.
Note:
To obtain a 5 V output, you would need to adjust the resistor values. For example, if ( V_{\text{out}} = 5,V ) is desired with ( V_{\text{FB}} = 0.8,V ), then:
5 V=0.8 V(1+R1R2)⟹R1R2=50.8−1=6.25−1=5.25\Large 5\,V = 0.8\,V\left(1+\frac{R_1}{R_2}\right) \quad \Longrightarrow \quad \frac{R_1}{R_2} = \frac{5}{0.8} - 1 = 6.25 - 1 = 5.25
If you set ( R_2 = 10,kΩ ), then ideally:
R1=5.25×10 kΩ=52.5 kΩ\Large R_1 = 5.25 \times 10\,kΩ = 52.5\,kΩ
You may choose the nearest standard resistor value (e.g., 51 kΩ or 56 kΩ) and recalculate to fine-tune the output voltage.
toastedsteve

toastedsteve

is this capable of 5A output

flux

The TPS5430DDA is typically rated for an output current around 3A. This means that as configured, it is not capable of supporting a continuous 5A load.
For a 5A output, you would need to select a buck converter that is specified to handle currents in excess of 5A or consider paralleling appropriate devices designed for such loads.
Let me know if you need recommendations for alternative components or additional design adjustments.
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list all IC1 pins in a table format. For each pin provide its pin number, pin na...
dimagre

dimagre

@copilot list all IC1 pins in a table format. For each pin provide its pin number, pin name and function.
1y

copilot

Sure! Here's a table listing the pins of IC1 (TPS5430DDA), including the pin number, pin name, and expected function:

Table

Pin NumberPin NameFunction
1BOOTBootstrap capacitor connection
2NCNo connection
3NCNo connection
4VSENSEVoltage sense input
5ENEnable input
6GNDGround
7VINInput voltage
8PHPhase node
9GNDPADGround pad
If you need more information about any specific pin function, feel free to ask!
1y
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2
EN
VIN
vout
IC1
C3
Capacitance
100nF
R1
Resistance
33kΩ
L1
Inductance
10uH
D1
R2
Resistance
10kΩ
C1
Capacitance
100uF
GND

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Learn to Add a Component

12v - 5v converter placeholder

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This project involves designing a DC-DC buck converter circuit to efficiently step down a 12V input voltage to a stable 5V output voltage. The converter is suitable for various electronic applications requiring 5V DC supply from a 12V source.

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