ZHCSOR0 August 2021 TPS25868-Q1 , TPS25869-Q1
PRODUCTION DATA
The recommended switching frequency of the TPS2586x-Q1 is in the range of 250–400 KHz for high efficiency. Choose RFREQ = 49.9 kΩ for 400-KHz operation. To choose a different switching frequency, refer to Table 10-1.
The choice of switching frequency is a compromise between conversion efficiency and overall solution size. Lower switching frequency implies reduced switching losses and usually results in higher system efficiency. However, higher switching frequency allows the use of smaller inductors and output capacitors, and hence, a more compact design. In automotive USB charging applications, it tends to operate at either 400 kHz below the AM band, or 2.1 MHz above the AM band. In this example, 400 KHz is chosen.