Tracking provides a predictable method of slewing the output voltages up or down. Tracking generally holds the feedback voltage to the lesser of the internal reference voltage or the voltage on the TRACK pin. The LTC3850 goes further by combing track and soft start functions (TK/SS pin) in a single pin for each channel and by tailoring the mode of switching operation to the state of this TK/SS pins. Figure 3 shows coincident and ratiometric tracking, either of which can be configured using the LTC3850.

Figure 3a: Coincident mode of output voltage tracking with the LTC3850.
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Figure 3b: Ratiometric mode of output voltage tracking with the LTC3850.
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