Silan continuously unveiled new products in green power controller field ---- the primary side control SMPS SD6853/6854 with built-in 650V MOSFET. These series circuits provide programmable cable loss compensation and peak current compensation, and using PFM technology provide accurate constant voltage/constant current (CV/CC) control loop with high stability and average efficiency, which make them widely used in mobile phone chargers, small power adapters, standby power, MP3 and other portable devices.

SD6853/6854is high end off-line SMPS controller with built-in high voltage MOSFET, cable loss compensation and peak current compensation. It uses Silan's patented technology. The circuit achieves the constant output voltage or current by indirect control through detecting the primary winding current and the auxiliary winding feedback voltage of the transformer. In a certain output power range, the output voltage can be set by feedback resistor; and the output current can be set by peak current sensing resistor. The cable loss compensation and peak current compensation can be set according to the requirements to achieve the best regulation rate of output voltage and output current.

The normal operating cycle is divided into peak current detecting and feedback voltage detecting: when the MOSFET is on, the primary winding current is detected by sensing resistor, the load is powered by output capacitor and the output voltage VOUT decreased; When the primary winding current reaches to the peak value, the MOSFET is off and the voltage on pin FB is detected. The output capacitor is charged by the energy stored in secondary winding and the output voltage VOUT increased to power the load. When the open conditions of constant voltage and constant current circuits are satisfied at the same time, the MOSFET is on and the circuit enters the peak current detection again.

In addition, the device integrates various protection circuits such as over temperature protection, loop open protection, current limit, over voltage protection, and under voltage lockout etc. to ensure the normal operating environment and prolong its service life.

At present, 4.0W output power (5V /800mA) is available for SD6853, 5.0W output power (5V /1A) is available for SD6854, and the average efficiency is more than 68% (using 1.8 m AWG28 cable); the standby power dissipation is less than 100mW; the load regulation rate of output voltage is less than ±4.0%and the input line voltage regulation rate of output voltage is less than ±0.6%; the ESD of the whole system is more than ±15KeV. In the following, 3W~5W output power will be available for SD6853 and 5W~12W output power will be available for SD6854.

SD6853/6854 is based on 0.8

Share
© Publicnow - 2011