SLVSF07 July 2021 TPS7H5001-SP
ADVANCE INFORMATION
Since the TPS7H5001-SP uses a transconductance error amplifier (OTA), either Type 2A or Type 2B frequency compensation can be applied. The primary difference between the two compensation schemes is that Type 2A has an additional capacitor C_{HF} in parallel with R_{COMP} and C_{COMP} in order to provide high-frequency noise attenuation. These components will be connected between the COMP pin of the controller, which is the OTA output, and AVSS.
For any of the topologies supported by the TPS7H5001-SP, the following procedure and equations can be used to select the compensation components. All parameters in the equations are in standard units unless otherwise indicated (that is, H for inductance, F for capacitance, Hz for frequency, and so on).
where:
For different power converter topologies, the primary change to the compensation selection procedure will be the determination of the power stage transconductance gm_{PS}. The power stage transconductance can be calculated as shown in Equation 23.
Note that for the TPS7H5001-SP, the sensed current waveform is compared to the voltage at COMP divided down by the factor CCSR at the PWM comparator, which is accounted for in the denominator of the equation. For buck converters, all turns for the main power transformer can be set equal to 1 and the equation still applies.