Fairchild's PWM controller realizes ultra-low standby power consumption of charger

Mobile phone chargers are often left plugged in for long periods, even when not actively charging. This idle state still draws power, leading to unnecessary energy waste and higher electricity bills. For engineers, the challenge is clear: how to minimize this standby power consumption to save energy, meet regulatory standards, and ultimately reduce costs for end users.

To tackle this issue, Fairchild Semiconductor, a global leader in high-performance power and mobile solutions, has introduced the FAN302HL PWM controller. This ultra-low standby power solution utilizes mWSaver™ technology and patented innovations to drastically cut input power during standby—less than 10mW at 230VAC, surpassing the five-star requirements of the ENERGY STAR® computer specification.

The FAN302HL is a highly integrated PWM controller that enhances the performance of general-purpose flyback converters. It features an integrated 500V JFET, which cuts off the current path during startup, reducing losses. Its patented constant current control topology simplifies circuit design by eliminating the need for a secondary-side feedback circuit, making it ideal for battery charger applications.

The device also includes robust protection features, such as cycle-by-cycle current limiting, ensuring a fixed peak current limit even in case of a short circuit. Additionally, the gate output voltage is clamped at 15V to protect the power MOSFET from excessive gate-to-source voltage damage.

Importantly, the FAN302HL does not require an external secondary overvoltage protection (OVP) circuit. If either the OVP function on the VS pin or the internal overtemperature protection is triggered, the device enters a lock mode until the AC power is disconnected. This eliminates the need for secondary-side OVP components while enhancing VO protection (<6V).

By leveraging innovative technologies like primary-side regulation, the FAN302HL reduces power losses in both the power MOSFET and PWM IC. It eliminates the need for secondary-side current sensing, lowering power consumption and boosting efficiency. The controller also operates in an intermittent mode with low operating current, further minimizing standby power usage.

In addition, the FAN302HL uses secondary-side regulation for constant voltage control, offering excellent dynamic response to meet USB 2.0 specifications. Compared to traditional designs or linear transformers, using the FAN302HL in charger designs reduces the number of external components, lowers costs, and improves overall system performance.

Beyond mobile phone chargers, the FAN302HL is suitable for a wide range of applications, including smartphones, wireless devices, DVD players, set-top boxes, Power Over Ethernet (PoE), and small household appliances.

The FAN302HL comes in an 8-pin compact package with a fixed PWM frequency of 85kHz and a frequency-jittering feature to reduce electromagnetic interference (EMI). It is part of Fairchild's mWSaverâ„¢ product family, designed to deliver optimal power savings and minimal component count.

Fairchild Semiconductor continues to drive innovation in power management solutions, helping engineers create smarter, more efficient products. With the FAN302HL, they offer a powerful tool to address the growing demand for energy-efficient electronics.

Price (order 1,000): $0.50

Availability: Samples available now

Delivery time: 8 to 10 weeks after order placement