onsemi NCP12510BSN100T1G

The NCP12510 is a highly integrated PWM controller capable of providing a robust and high-performance offline power supply in a tiny TSOP-6 package. The controller has a voltage supply range of up to 35 V and features a jittering 65 kHz or 100 kHz switching circuit operating in peak current mode control. When the power on the secondary side begins to decline, the controller automatically folds back its switching frequency to a minimum of 26 kHz. As the power further decreases, the device enters skip cycle mode while limiting the peak current. onsemi's proprietary integrated over-power protection (OPP) allows the maximum output power to be utilized through two external resistors without affecting standby performance. An over-voltage protection (OVP) input is also integrated on the same pin, which can protect the entire circuit in case of optocoupler damage or adverse open-loop operation. Finally, the timer-based short-circuit protection provides an optimal protection scheme, allowing for precise selection of the protection trigger point without worrying about the loose coupling between the auxiliary winding and the power winding.

The NCP12510 is an improved and pin-compatible controller based on the very popular flyback controller NCP1250. The NCP12510 implements a standard current mode architecture where the turn-off event is determined by the peak current setpoint. This component is an ideal choice where low component count and cost-effectiveness are key parameters, especially in applications such as low-cost AC - DC adapters and open power supplies.

The updated controller NCP12510 integrates all the necessary components typically required in today's modern power supply designs, bringing several improvements such as lossless OPP, OVP/OTP implementation, short-circuit protection with pre-short function (for the latch version), and improved power consumption, robustness, and ESD capability.

Current Mode Operation with Internal Slope Compensation: The NCP12510 implements peak current mode control at a switching frequency of 65 or 100 kHz, providing an internal slope compensation signal that can be easily added to the sensed current. Therefore, sub-harmonic oscillations can be suppressed by connecting a simple resistor in series with the current sensing information.

Internal OPP: By routing a portion of the negative voltage present during the auxiliary winding conduction period to the dedicated OPP pin (Pin 3), the user can change the maximum peak current setpoint in a simple and lossless manner as the bus voltage increases. If this pin is grounded, no OPP compensation occurs.

• Fixed−Frequency 65 kHz or 100 kHz Current−Mode Control Operation
• Frequency Foldback Down to 26 kHz and Skip−Cycle in Light Load Conditions
• Frequency Jittering in Normal and Frequency Foldback Modes
• Internal and Adjustable Over Power Protection (OPP) Circuit
• Auto−Recovery Over Voltage Protection (OVP) on the VCC Pin
• Internal and Adjustable Slope Compensation
• Internal Fixed 4 ms Soft−Start
• Auto−Recovery or Latched Short−Circuit Protection
• Pre−Short Ready for Latched OCP Version
• OVP/OTP Latch Input for Improved Robustness
• +300 mA/-500 mA Source/Sink Drive Capability
• Improved Consumption Players
• Improved Reset Time in Latch State
• High Robustness and High ESD Capabilities
• EPS 2.0 Compliant
• This is a Pb−Free Device

• Ac−dc Converters for TVs, Set−top Boxes and DVD
• Offline Adapters for Notebooks and Netbooks