Simple DC to DC Adjustable Converter Circuit using IC TL497A

This DC to DC adjustable converter circuit with the TL497A chip is like a little helper that can adjust the voltage of your power source.

It can take a lower voltage and give you a higher voltage just like a mini power adapter.

The cool thing is, this circuit can be adjusted configured to work in different ways, depending on what kind of voltage change you need.

Whether you need a small boost or a big jump, this circuit can handle it.

The TL497A chip uses a clever technique called PWM to make the voltage conversion efficient.

Circuit Working:

Parts List:

This voltage converter, utilizing the TL497A transforms input voltages ranging from 5 to 12V into a higher range of 15 to 30V.

This feature is particularly advantageous in mobile applications where power supplies typically top out at 12V, sourced from batteries.

The converter circuit employs the TL497A as a flyback voltage converter, with a 40uH 2A choke coil.

Capacitors C2 and C1 are utilized to suppress voltage spikes.

The maximum output current is contingent on the discrepancy between input and output voltages, hovering around 100mA.

The ripple voltage remains relatively low.

Standby current is approximately 8mA, and efficiency is estimated at 70%.

Formulas:

From the above circuit there is a generic flyback converter formulae, but further analysis and simulations are needed to get exact numbers for a certain design.

Although the TL497A is a flexible integrated circuit, its use in flyback converters necessitates intricate relationships between various parts and operational parameters.

Below are some key formulas:

Duty Cycle D:

D = V_out / (V_out + V_in) * N_p/N_s

where,

• V_out is the output voltage
• V_in is the input voltage
• N_p is the number of turns in the primary winding
• N_s is the number of turns in the secondary winding

Inductor Value L:

L = (V_in * D * T_on) / (ΔI_pk)

where,

• T_on is on time of the switch
• ΔI_pk is peak to peak inductor current ripple

Output Voltage Ripple ΔVout:

ΔV_out = I_out / (f * C_out)

where,

• I_out is the output current
• f is the switching frequency
• C_out is the output capacitor

Note:

The TL497As integrated oscillator, output driver and error amplifier reduce complexity in some areas of the design.

Nonetheless, it is still necessary to carefully analyze the values of the component parts and external circuitry.

Recall that this is a condensed summary, a thorough examination and a multitude of trade offs are necessary when designing a flyback converter.

For more thorough instructions, consult the program notes and think about utilizing simulation tools.

How to Build:

To build a Simple DC to DC Adjustable Converter Circuit using IC TL497A follow the below mentioned steps:

Schematic Design:

• Create a schematic based on the TL497A datasheet for the flyback converter circuit.
• Ensure that the components are selected based on the required output voltage range 15 to 30V and maximum output current 100mA.

PCB Layout:

• Design a PCB layout based on the schematic.
• Place components to minimize noise and ensure proper functioning of the circuit.

Component Placement:

• Solder the components onto the PCB according to the layout.
• Be careful with polarized components like capacitors and diodes.

Testing:

• Test the circuit with a variable input voltage within the specified range 5 to 12V to verify that the output voltage is within the desired range 15 to 30V.
• Use a multimeter to measure the output voltage and current.

Fine-tuning:

• If necessary, adjust component values or circuit parameters to achieve the desired output voltage and current characteristics.

Enclosure:

• Once the circuit is working correctly consider enclosing it in a suitable casing to protect it from environmental factors.

Final Testing:

• Perform final tests to ensure that the converter meets all requirements and functions reliably.

Note:

• It is essential to follow the TL497A datasheet and guidelines for proper circuit design and component selection to ensure the converter operates safely and efficiently.

Conclusion:

To conclude, the DC to DC adjustable converter circuit using the TL497A IC offers a flexible and efficient solution for converting lower input voltages to higher output voltages.

Its versatility in different converter topologies and its ability to adjust output voltages make it suitable for a wide range of applications, including mobile devices, automotive electronics and other battery powered systems.

With its features for voltage regulation and overcurrent protection the TL497A IC enables the design of reliable and stable power supply solutions for various electronic devices.

References:

DC-to-DC converter

Datasheet IC TL497A