Low power consumption and low power 10W power supply chip U9513B

With the advent of single-chip control switching power supply, switching power supply adapters have also surpassed power frequency transformer adapters with a strong momentum of development. This phenomenon is more obvious in the field of portable chargers for rechargeable batteries. Switching power supply has the advantages of small size, light weight, high efficiency, high integration, high cost performance, simple peripheral circuit, etc., and is favored by engineers. The low-power 10W power supply chip U9513B introduced below has low consumption, low cost, simple and mature solution, and is very popular!

The low-power 10W power supply chip U9513B before the chip starts to work, the ic only consumes a typical start-up current of 1.1uA, and the ultra-low start-up current can help increase the start-up resistance to reduce standby power consumption . When the VDD voltage exceeds the turn-on voltage (typical value 10V), U9513B starts to work and the chip operating current rises to 0.18mA (typical value). Afterwards, the VDD capacitor continues to supply power to the chip until the output voltage is established, and the auxiliary winding supplies power to the chip. Once the chip enters the ultra-low frequency working mode, the operating current of U9513B is further reduced to 0.14Ma (typical value) to help reduce system standby power consumption.

U9513B

The 10W power supply chip U9513B uses the timing relationship between the FB pin voltage and the CS pin voltage to achieve high-precision constant current output control. In the constant voltage output mode, when the system output power increases and approaches the constant current output control point, the primary inductor current reaches its maximum value. The primary inductor current, transformer turns ratio, secondary demagnetization time (Tdem) and switching cycle time (Tsw) determine the secondary average output current. If the influence of leakage inductance is ignored, the formula for the average output current of the secondary side can be seen in the detailed data diagram. When the output current reaches the output reference of the primary side constant current control module, the chip will enter the frequency modulation mode, no matter the output voltage is lower than the constant voltage output reference or what the specific situation is, as long as the VDD voltage is not lower than its shutdown voltage, the chip will continue to work .

The 10W power supply chip U9513B integrates single-point failure protection, including FB pull-up resistor open circuit, FB pull-down resistor open circuit, FB pull-down resistor short circuit, output diode or SR open circuit, output diode or SR short circuit, transformer winding short circuit , RCS open circuit and other protection. The IC's single-point failure protection function can ensure that the IC is not damaged and the output does not generate overvoltage. When the temperature of the chip exceeds 160°C, the chip will stop working, and only when the chip temperature drops to 135°C can the chip restart to work. The dynamic response performance of the optimized design can meet the requirements of USB chargers.

In the constant voltage output mode, the chip uses a frequency modulation control pin with a current source flowing out to adjust the CS voltage signal. Using the above technologies, the 10W power supply chip U9513B can work from full load to no load without any abnormal sound. U9513B integrates triode base dynamic drive technology to optimize system efficiency. Base drive current dynamically adjusts with load conditions. The larger the output load, the larger the base drive current, and the base drive current is proportional to the peak voltage signal of the CS pin. The multi-mode control technology combined with the amplitude modulation control, and the peak voltage signal of the CS pin at the same time.

In the design of low-power power supply chips, Shenzhen UnionPay Technology pays attention to space layout, compatibility issues and cost pressures. , Space cost to achieve the maximum benefit!