The 8-pin DPA Switch device features a wide d.c. input voltage range of 16 to 75 V d.c., eliminating the use of multiple integrated IC solutions. The device’s control scheme also supports three converter topologies—forward, flyback, and buck.
The DPA-Switch family, named for its compatibility with Distributed Power Architectures (DPAs), operates with an input voltage range of 16- to 75-V and is said to provide up to 100 W of continuous output power. The six new part types in the IC family are said to eliminate more than 20 components compared to a typical MOSFET plus PWM controller d.c./d.c. converter design.
“Power Integrations specifically designed its 8-pin DPA-Switch device packages to use the copper of the printed circuit board, which connect to the source pins of the package, as the heatsink for the device,” says John Jovalusky, technical marketing engineer for the San Jose, CA, U.S.-based company. “This reduces the component cost and the manufacturing labor cost of the end-solution power supply since neither an external heatsink nor the labor of assembling it are required.”
The device’s 220-V MOSFET switch features low switching losses, as it switches efficiently at high frequencies (300 and 400 kHz). “This allows the magnetic components to be as small as possible, keeping solution cost, size, and weight as low as possible,” Mr. Jovalusky tells APPLIANCE.
In addition, the device features an automatic soft-start at the initial startup, at each restart attempt, and during auto-restart operation. This, according to Mr. Jovalusky, eliminates the stress put on other power components when a converter starts switching at normal values by taking the duty cycle and the current limit of the device from minimum values as switching begins, and gradually increasing the device up to normal values during a 5-msec period.
The auto-restart feature prevents the conversion solution from delivering more power to the load than intended by attempting to restart the converter once every eighth switching cycle. “It will automatically recover when the fault is cleared and resume normal operation,” Mr. Jovalusky explains. “While it is in auto-restart mode, the power delivered to the output is limited to about 5 percent of the full-load rated power.”
Due to its simple design and high-efficiency, the device is also said to help simplify the design process. “All of the functions and features are already integrated into the device,” says Mr. Jovalusky. “The designer can just use them and count on them to work.”