LNK6669E

LNK6669E is a high performance current-mode quasiresonant (QR) flyback converter controller. The controller implements an adaptive on time control scheme, where the switching frequency is adjusted dynamically based on the output current. LNK6669E is a high-efficiency, low-cost off-line switcher for isolated low-power AC-DC applications, such as cell phone chargers, power supplies, game consoles and other non-isolation DC-DC applications. The device provides superior EMI reduction due to its wide operating frequency range of 20 kHz to 200 kHz, programmable switching frequency, frequency jitter and spread spectrum techniques.

The LNK6669E can operate in current mode or voltage mode. In current mode, it is suitable for applications requiring accurate current regulation, such as LED drivers and motor drives. In voltage mode, it is suitable for applications requiring stable output voltage, such as off-line switchers for low-voltage AC-DC adapter applications. The device can be easily configured for either operation mode with a simple setting of the sense status during device initialization.

The LNK6669E can be configured to operate in various topologies such as flyback, forward, push-pull and half-bridge. It supports both single and dual winding designs. The controller is able to monitor two primary side voltages, two primary side currents, one secondary side current and one external temperature sensor. It is also capable of detecting single, dual, rd-cycle and short circuit secondary side faults and generating necessary protection signals.

The LNK6669E can be configured to work with PFC pre-regulator. Its dynamic biasing feature is able to keep the output voltage of the PFC stage nearly constant over the whole duty cycle range of the QR converter. This feature facilitates the design of higher efficiency systems by eliminating the need for complex compensation loops.

The main features of the LNK6669E includes over-current protection (OCP), over-voltage protection (OVP), power good indicator, auto-restart, soft start, frequency foldback, dynamic biasing, spread spectrum, and programmable switching frequency. These features ensure the safe operation of the converter, high system efficiency, stable output voltage and improved EMI performance.

The LNK6669E is designed to provide high integration\' and high performance for small form-factor AC-to-DC off-line switcher applications. This device is optimized for low-cost applications by reducing component count, PCB area and component complexity. The integration of the OCP, OVP and other important built-in protection functions reduces the cost of an external protection circuit.

The LNK6669E is a highly integrated, high-efficiency, low-cost off-line switcher for isolated low-power AC-DC applications. By using the device, system designers can reduce component count, design complexity, board cost and system size while achieving high efficiency, improved EMI performance and reliable operation.