How do flying capacitor boosters work?

In the flying capacitor booster topology the two transistor have to be controlled by 180° phase shifting (Figure 4). = 0.5, the operation modes will change between Mode 2 and Mode 3. The typical curves of the flying capacitor booster can be seen on Figure 5 in case of

What is a three-level flying capacitor booster?

With this offset the three-level flying capacitor booster can be considered as two standalone Booster, where the outer one’s commutation loop includes the DC-link capacitor, the outer diode, the flying capacitor and the outer switch. The inner commutation loop includes the flying capacitor, the inner diode and the inner switch.

What is the difference between a charge-pump converter and a magnetic boost?

When looking at eficiency curves and comparing the two types of converters, a typical charge-pump converter has a sawtooth shape as the input voltage changes, while the magnetic boost has a nearly flat-line profile. From a power perspective, the inductive-based solution is usually more eficient than the charge-pump solution.

How does a boost converter work?

The switch node and output voltage of the boost converter generate an unregulated auxiliary positive output voltage that is roughly twice the main output voltage. An additional linear regulator or simple regulation transistor with a Zener diode can easily be added to the output of the charge pump for voltage regulation.

How do you regulate the output voltage of a charge pump?

The usual way to regulate the output voltage of a charge pump is to put an adjustable current source, I1, in series with switch S1, or S2 in the case of an inverting charge pump (see Figure 3). The error amplifier, A1, adjusts the value of I1 until the output voltage is correct. Under steady-state conditions, I1 is exactly twice the value of IO.

Why should a resistor be placed before a flying capacitor?

Placing a resistor before the flying capacitor helps to reduce the current spikes if the capacitor is not charged to its nominal value. This current must be limited because it can lower circuit efficiency and degrade the charge pump performance.