JAJSLY1G July 2013 – June 2021 TPS54561
PRODUCTION DATA
The TPS54561 uses a transconductance amplifier for the error amplifier and supports three of the commonly-used frequency compensation circuits. Compensation circuits Type 2A, Type 2B, and Type 1 are shown in Figure 7-19. Type 2 circuits are typically implemented in high bandwidth power-supply designs using low ESR output capacitors. The Type 1 circuit is used with power-supply designs with high-ESR aluminum electrolytic or tantalum capacitors. Equation 18 and Equation 19 relate the frequency response of the amplifier to the small signal model in Figure 7-19. The open-loop gain and bandwidth are modeled using the RO and CO shown in Figure 7-19. See the application section for a design example using a Type 2A network with a low ESR output capacitor.
Equation 18 through Equation 27 are provided as a reference. An alternative is to use WEBENCH software tools to create a design based on the power supply requirements.