UC3869AG-S08-R datasheet(7/9 Pages) UTC

7 / 9 page

UC3869A

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

7 of 9

www.unisonic.com.tw

QW-R103-143.B

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OPERATION DESCRIPTION (Cont.)

Gate Output

The UTC UC3869A output stage is a fast totem pole gate driver. Cross conduction has been avoided to minimize

heat dissipation, increase efficiency, and enhance reliability. A good tradeoff is achieved through dead time control.

The low idle loss and good EMI system design is easier to achieve with this dedicated control scheme. An internal

16V clamp is added for MOSFET gate protection at higher than expected VDD input.

Protection Controls

The IC takes on more protection functions such as OVP, OLP and OTP etc. In case of those failure modes,the

driver works as follows.

OVP

The OVP will shut down the switching of the power MOSFET whenever VDD >VOVP. The OVP event as followed

Fig.3.

Fig.3 OVP case

Fig.4 OLP case

OLP

OLP will shut down driver when VFB> VOLP for continual a blanking time. The OLP event as followed Fig.4.

OTP

OTP will shut down driver when junction temperature TRT<VTH_OTP

UC3869AG-S08-R Arkusz danych(PDF) 7 Page - Unisonic Technologies