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|Fairchild Semiconductor’s CRM PFC Controller ICs Feature Industry-Leading THD Performance, Low Standby Power to Meet PFC/Energy Regulations|
South Portland, Maine–Fairchild Semiconductor introduces critical conduction mode (CRM) power factor correction (PFC) controller ICs specially designed to meet stringent stand-by power and harmonic regulations affecting ballast, notebook adaptors, LCD TVs and LCD monitors. The FAN7529 and FAN7530 utilize a patent-pending variable on-time control method to achieve industry-leading Total Harmonic Distortion (THD) performance (<10 percent at 25 percent load, 265Vac) for excellent system reliability.
They also easily meet stand-by power regulations by reducing input-voltage sensing loss to approximately 100mW. These highly integrated PFC controllers, the FAN7529/FAN7530, eliminate components compared to both passive solutions and similar controllers on the market, therefore helping designers to reduce part count and save system costs.
“Fairchild’s FAN7529 and FAN7530 PFC controllers offer designers the best THD performance on the market, an important consideration since government regulations specify that manufacturers must reduce harmful noise that can affect system reliability,” said CJ Kim Fairchild’s product manager, Power Conversion product line. “Fairchild uses a unique variable on-time control method based on ZCD winding voltage to achieve less than 10 percent THD at 25 percent of the full load. As a result, when designing four lamp ballasts, a designer can control THD to be less than 10 percent even if only one lamp is turned on. This low THD translates into excellent system performance and offers more flexibility to system designers.”
Fairchild’s FAN7529 and FAN7530 utilize an internal voltage-mode PWM method compared with conventional current-mode controllers requiring rectified AC-line voltage information even when the PFC IC does not operate. As a result, Fairchild’s CRM PFC controllers reduce overall power loss by approximately 200mW. Moreover, Fairchild’s controllers offer a disable function to further reduce power consumption during stand-by mode, and their current-type error amplifiers enable these devices to use a higher Rfb (output-voltage-sensing resistor) over 1 megaohm, resulting in reduced power loss (80 milliwatts, 2 megaohms).
To increase system reliability, Fairchild’s controllers feature open-feedback protection and a disable function (65 microamps), making Vcc shut-down circuitry unnecessary. They also offer adjustable-output over-voltage protection (OVP) of plus/minus 2%. This type of voltage-sensing OVP is immune to noise. The devices also offer a 150 microsecond internal start-up timer, MOSFET over-current protection and under-voltage lockout with 3.5V hysteresis.
In addition to these PFC controllers, Fairchild also offers the FAN7528, a dual-output CRM PFC controller IC. The FAN7529 and FAN7530 add to Fairchild Semiconductor’s offering of discrete and IC product solutions, the broadest in the industry targeting switch-mode power supplies from 1W to 1500W.
The FAN7529 and FAN7530 are offered separately as pin-out options for meeting specific requirements and design preferences. Both are available in DIP-8 and SOP-8 packages. These lead-free products meet or exceed the requirements of the joint IPC/JEDEC standard J-STD-020C and are compliant with the European Union requirements which are now in effect.
Martes, 12 Diciembre, 2006 - 08:59