ZHCSCG9C May 2014 – July 2019 TPS62150A-Q1 , TPS62152A-Q1 , TPS62153A-Q1
PRODUCTION DATA.
The devices of the TPS6215xA-Q1 family are internally compensated to be stable with L-C filter combinations corresponding to a corner frequency to be calculated with Equation 12:
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Proven nominal values for inductance and ceramic capacitance are given in Table 3 and are recommended for use. Different values may work, but care has to be taken on the loop stability which is affected. More information including a detailed LC stability matrix can be found in SLVA463.
The TPS6215xA-Q1 includes an internal 25pF feedforward capacitor, connected between the VOS and FB pins. This capacitor impacts the frequency behavior and sets a pole and zero in the control loop with the resistors of the feedback divider, per equation Equation 13 and Equation 14:
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Though the TPS6215xA-Q1 is stable without the pole and zero being in a particular location, adjusting their location to the specific needs of the application can provide better performance in Power Save mode and/or improved transient response. An external feedforward capacitor can also be added. A more detailed discussion on the optimization for stability versus transient response can be found in SLVA289 and SLVA466.