HOME Products Flyback ICs OB276N
OB276N
GENERAL DESCRIPTION
OB276N is a high performance, high precision and low cost off-line switcher with enhanced flexibility and extended power range. It combines a dedicated on/off switch controller with a high voltage power MOSFET in DIP7 package. Its on/off control scheme is optimized for good overshoot and dynamic response for low cost and component count. With precise current sensor, precise on/off control scheme， constant current at universal AC input can be guaranteed. Good EMI performance is achieved with On-Bright proprietary frequency shuffling technique and soft gate driver design. Low startup current and low operating current contribute to a reliable power on startup and low standby power consumption with OB276N.
OB276N offers power on soft start control and protection coverage with auto-recovery features including cycle-by-cycle current limiting, output short circuit protection, on-chip Over Temperature Protection (OTP), VDD Over Voltage Protection (OVP), Over Loading Protection(OLP) and VDD Under Voltage Lockout Protection (UVLO).
OB276N is offered in DIP7 package.
FEATURES
· Simple ON/OFF control, no loop compensation needed.
· Low cost and less BOM for off-line Switcher applications
· Current mode control
· 132kHz (typical) maximum switching frequency
· Frequency shuffling for EMI improvement
· Power on soft-start
· No load<200mW at 265VAC, Without bias winding, <50mW with bias winding.
· Built-in Leading Edge Blanking (LEB)
· Cycle-by-cycle current limiting
· Output short-circuit protection
· VDD Under Voltage Lockout with Hysteresis
· VDD OVP
· Over Loading Protection
· On-Chip OTP
APPLICATIONS
· Chargers/adapters for cell/cordless phones, PDAs, digital cameras, MP3/portable audio, shavers, etc.
TYPICAL APPLICATION
GENERAL INFORMATION
Pin Configuration
The pin map is shown as below for DIP7
Ordering Information
Part Number | Description |
OB276NASP-V | DIP7, Halogen-free, Tube |
Package Dissipation Rating
Package | RθJA (℃/W) |
DIP7 | 75 |
Note: Drain Pin Connected 100mm2 PCB copper clad.
Recommended Operating Condition
Symbol | Parameter | Range |
VDD | VDD Supply Voltage | 8.5-15V |
Output Power Table
Flyback | 85~275Vac (Adapter) | 176~275Vac (Adapter) |
OB276N | 7W | 10W |
Notes: Maximum practical continuous power in an adapter design with sufficient drain pattern as a heat sink, at 40℃ambient.
Absolute Maximum Ratings
Parameter | Value |
SW Voltage(off state) | -0.3V to 700V |
VDD Input Voltage | -0.3V to 22V |
FB Input Voltage | -0.3V to 7V |
Min/Max Operating Junction Temperature TJ | -40 to 150 ℃ |
Min/Max Storage Temperature Tstg | -55 to 150 ℃ |
Lead Temperature (Soldering, 10secs) | 260 ℃ |
Note: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute maximum-rated conditions for extended periods may affect device reliability.
Marking Information
TERMINAL ASSIGNMENTS
Pin Num | Pin Name | I/O | Description |
1 | FB | I | Feedback pin |
2 | VDD | P | Power Supply |
4 | SW | I | Power MOSFET Drain pin |
5/6/7/8 | GND | P | Ground |