OB2633L is a highly integrated Quasi-Resonant(QR) controller with adaptive multi-mode regulation, optimized for high performance, low standby power consumption and wide output voltage range Quick Charger(QC) solutions, together with secondary -side controllers, such as OB2019 and OB2601 supporting Qualcomm Quick Charge QC 3+ 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 77KHz. 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.
VDD low startup current and low operating current contribute to a reliable power on startup and low standby design with OB2633LMP.
OB2633L offers complete protection coverage including cycle-by-cycle current limiting (OCP), over load protection (OLP), over temperature protection (OTP), output UVP, output short(SCP), 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.
OB2633L is offered in SOT23-6 package.
Offline AC/DC flyback converter for
■ Quick-charging AC/DC charges
■ AC/DC Adapters with wide output range
■ Multi-Mode Operation
87KHz maximum operation frequency in CCM mode @ Peak Load in low line voltage
77KHz 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
■ Very wide range of supply voltage
■ Low operating current at light/no load
■ Internal OCP compensation for universal line voltage
■ Extended burst mode control for improved efficiency and low standby power
■ Power on soft start reducing MOSFET Vds stress
■ Frequency shuffling for EMI
■ Audio noise free operation
■ Comprehensive protection coverage
o VDD under voltage lockout with hysteresis (UVLO)
o Cycle-by-cycle over current protection (OCP) with auto-recovery
o Overload protection (OLP) with auto-recovery
o Over temperature protection (OTP) with auto-recovery VDD over voltage protection with auto-recovery Output over voltage protection with auto-recovery
o Output short protection (SCP) with auto-recovery
o Output diode short protection with auto-recovery
o Output Under Voltage Protection(Output
UVP) with auto-recovery
OB2633LMP Typical Application