OB2633G

GENERAL DESCRIPTION

OB2633x is a highly integrated Quasi-Resonant(QR) controller with adaptive multi-mode regulation, optimized for high performance, low EMI, low standby power consumption and wide output voltage range Quick Charger(QC) solutions, together with secondary -side controllers, such as OB2004Ax and OB2603x supporting Qualcomm Quick Charge QC3.0 protocol. The controller is as well compatible with cost effective offline flyback converter applications covering a wide output range.

At normal load condition, it operates in QR mode in high line input voltage. To minimize switching loss, the maximum switching frequency in QR mode is internally limited to 92KHz. When the loading goes low, it operates in PFM mode with valley switching for high power conversion efficiency. When the load is very small, the IC operates in ‘Extended Burst Mode’ to minimize the standby power loss. Additionally, in the low line input voltage, the IC operates in fixed frequency (65KHz) CCM mode at the heavy loading. As a result, high conversion efficiency can be achieved in the whole loading range.

OB2633x offers complete protection including cycle-by-cycle current limiting (OCP), over load protection (OLP), over temperature protection (OTP), output short protection (SCP), output under voltage protection (UVP), output and VDD over voltage protection.  Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique.

The tone energy at below 22KHz is minimized to avoid audio noise during operation.

OB2633x is offered in SOT23-6 package.


FEATURES

   Very wide range of supply voltage

   Multi-Mode Operation

92KHz maximum clamping frequency in QR mode  @ Full Load in high line voltage

65KHz minimum clamping frequency in CCM mode @ Heavy Load in low line voltage

Valley switching operation @ Green mode

  Burst Mode @ Light Load & No Load

   Power on soft start reducing MOSFET Vds stress

   Extended burst mode control for improved efficiency and low standby power

   Soft Start for elimination output over shoot

   Adaptive loop gain compensation with Iovp current detection

   Frequency shuffling for EMI

   Low operating current at no/light load

   Audio noise free operation

   Comprehensive auto-recovery protection

o    VDD under voltage lockout with hysteresis (UVLO)       

o    Cycle-by-cycle over current protection (OCP)

o    Overload protection (OLP)

o    Over temperature protection (OTP)

o    VDD over voltage protection

o    Output over voltage protection

o    Output short protection (SCP)

o    Output under voltage protection (UVP)

o    Output diode short protection


APPLICATIONS

Offline AC/DC flyback converter for

   Quick-charging AC/DC charges  

   AC/DC Adapters with wide output range


TYPICAL APPLICATION