The TPS61379-Q1 uses a triangle waveform to spread the switching frequency with ±10% of normal frequency. The frequency of the triangle waveform is typically 0.4% of the switching frequency. For example, if the normal switching frequency of TPS61379-Q1 is programmed to 2.2 MHz, the spread spectrum function modulates the switching frequency in the range of 1.98 MHz to 2.42 MHz in a triangle behavior with 8.8 kHz rate.

The spread spectrum is only available while the clock of the TPS61379-Q1 is free running at its natural frequency. Any of the following conditions overrides spread spectrum, turning it off:

• An external clock is applied to the MODE/SYNC pin.
• The device works in the PFM operation at light load.