When the voltage at the VIN pin is below the boost regulation voltage, the bypass switch is turned off. The TPS61094 works in Boost mode to regulate the output voltage. When the voltage at the VIN pin is 0.1 V above the boost regulation voltage, the boost operation stops and the bypass switch is turned on. To make the transfer between Boost mode and Bypass mode smooth, there is a Pass-through mode when the input voltage is close to thetarget output voltage, as shown in Figure 7-6. The quiescent current at pass through mode is much higher than boost mode and bypass mode because the TPS61094 can detect the high-side MOS current.

Figure 7-6 Typical Supplement Operation Circuit