Description:
Based on feedback from Professor Krachey of the ECE department, we need to change our voltage converter from a Linear Drop-Out Regulator (LDO) to a Switching Buck Converter for power efficiency. Currently, our design uses an LDO, which is around 60% efficient. We are changing to a buck converter, which can be up to 99% efficient. This will allow the LAD's battery to last much longer. We also need the buck converter to have an enable pin in case we need to implement the on/off switch through enable pins instead of in series with the battery.
Background Information
A Linear Drop-Out Regulator (LDO) steps a voltage down from a higher voltage to a lower voltage. In our case, it steps 24V down to 5V. An LDO does this by dissipating all the excess power as heat. While this is a simple method and acceptable for our 5V to 3.3V converter, it is not efficient for such a large voltage change that occurs in the 24V to 5V converter.
A Buck Converter also steps a voltage down from a higher voltage to a lower voltage. However, it does this using switching mechanisms and higher-order circuit components. There are also circuits called boost converters, which use a similar switching mechanism to step up a voltage instead of stepping it down.
Responsibilities
References:
- The theory behind switching converters like the buck converter is quite complicated. Luckily, Texas Instruments provides software that does most of the heavy lifting for us. This way, we can focus on the implementation rather than knowing all the technicalities of the design.
- Use TI Power Designer to create the design. You will have to read the battery's datasheet (for min/max Vin) and look at the schematic to determine the parameters to enter into TI Power Designer. Make sure to consider how much output current the buck converter needs to be able to supply the motor driver and the 5V to 3.3V LDO
- LTSpice is a free circuit simulation software that you may decide to use (you will use this in future classes). TI Power Designer and Altium may also have built-in circuit simulation software, though I have never used them.
Description:
Based on feedback from Professor Krachey of the ECE department, we need to change our voltage converter from a Linear Drop-Out Regulator (LDO) to a Switching Buck Converter for power efficiency. Currently, our design uses an LDO, which is around 60% efficient. We are changing to a buck converter, which can be up to 99% efficient. This will allow the LAD's battery to last much longer. We also need the buck converter to have an enable pin in case we need to implement the on/off switch through enable pins instead of in series with the battery.
Background Information
A Linear Drop-Out Regulator (LDO) steps a voltage down from a higher voltage to a lower voltage. In our case, it steps 24V down to 5V. An LDO does this by dissipating all the excess power as heat. While this is a simple method and acceptable for our 5V to 3.3V converter, it is not efficient for such a large voltage change that occurs in the 24V to 5V converter.
A Buck Converter also steps a voltage down from a higher voltage to a lower voltage. However, it does this using switching mechanisms and higher-order circuit components. There are also circuits called boost converters, which use a similar switching mechanism to step up a voltage instead of stepping it down.
Responsibilities
References: