LT1509CN#PBF

LT1509CN#PBF is a power factor and PWM controller. It is a complete solution for universal off-line switching power supplies utilizing active power factor correction. The PFC section is identical to the LT1248 PFC controller except the EN/SYNC pin is removed because PFC and PWM are synchronized internally. The current mode PWM section (the LT1508 is the voltage-mode counterpart) contains all the primary side functions to convert the PFC preregulated high voltage output to an isolated low voltage output. The PWM duty cycle is internally limited to 47% (maximum 50%) to prevent transformer saturation. PWM soft start begins when PFC output reaches the preset voltage. In the event of brief line loss, the PWM will be shut off when the PFC output voltage drops below 73% of the preset value. It is used in applications such as universal power factor corrected power supplies and preregulators etc.

• PFC and PWM single chip solution
• Current mode PWM, instantaneous overvoltage protection
• 99% power factor over 20:1 load current range
• Dedicated overvoltage protection (OVP pin)
• Minimal line current dead zone
• Line switching noise filter
• Start-up supply current is 250µA typical
• Fast 2A peak current gate drivers, separate soft start controls
• Low quiescent current is 13mA typical at (11.5V ≤ VCC ≤ VMAX)
• Operating temperature is 0°C to 100°C, package style is 20-lead PDIP

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party