Datasheet TB9045FNG-120 (Toshiba) - 6

TB9045FNG-120
5. Functional description
Some of the functional blocks of the block diagram of this chapter, the circuit or constant labels, might have been omitted or simplified for clarity.
DCDC Convertor DCDC1
It is buck-boost DCDC convertor with input voltage VB1/2 and 6V output voltage. For buck mode, it is a synchronous rectifying type incorporating output driver MOS and rectification MOS. For boost mode, it is a diode rectifying type having external driver MOS and rectifier diode.  Switching frequency is 400 kHz.  It incorporates functions of overcurrent detection and high/low voltage detection (not used in low voltage detection).  It incorporates phase compensating capacitor.  The capacitor connected to DC1Css pin can control voltage rising time.  Buck mode enables use of DCDC convertor for buck mode (with BSTOFF = VDD set). Switching between buck-boost mode and buck mode during IC operation must not be performed.
At the time of using DCDC convertor for buck-boost mode
AGND BSTOFF VB2 VB1 (VDD) (VB2) (VB1) (VDD) (VDD) DC1SW1 (DC1SW1) (dc1idet) Over Current Detection DC1SW2 DCDC (DC1SW2) Cotrol PGND1 (PGND1) (VDD) DC1G2 (DC1G2) (VDD) Error Under DC1FB (dc1ldet_x) (DC1FB) Voltage Logic Detection (VDD) (vbg1) VBG1 (dc1hdet_x) Over Voltage Detection DC1Css (DC1Css) (vbg2) VBG2 (LDO1IN) LDO1IN (dc1ctl) © 2015-2019 2018-06-04 Toshiba Electronic Devices & Storage Corporation 6