RT8465ZS Richtek

RT8465 Constant Voltage High Power Factor PWM Boost Driver Controller for MR16 Application General Description Features zz z zz Wide Input Voltage Range : 8V to 32V The RT8465 is a constant output voltage, active high power zz z zz High Power Factor Correction with Simple System factor, PWM Boost driver controller. It can be used as the Circuits first Boost stage followed by a constant current Buck zz z zz Adjustable Constant Output Voltage converter with input from AC/electronic transformer in zz z zz Built-in High Power Factor Correction Circuit MR16/AR111 application. To achieve high power factor, zz z zz Typical 250A Start-Up Supply Current the AC input voltage from AC/electronic transformer is zz z zz Low Quiescent Current : 0.1A sensed via the SIN pin. An internal power factor correction zz z zz SOP-8 Package circuit follows the sensed sine waveform and modulates zz z zz RoHS Compliant and Halogen Free the external MOSFET duty cycle-by-cycle to achieve constant output voltage. Applications The output voltage is adjustable via an output resistive z MR16, AR111 Lamps divider. By operating at 220kHz, the filter component size z PFC Controller can be small to fit in tight MR16 space. To drive industrial grade MOSFET switches, the RT8465 gate driver can deliver up to 0.8A output current with 9V gate output voltage. Simplified Application Circuit L + D1 AC IN ~ D2 - RT8465 VCC R1 R2 SIN GATE M1 C2 C1 ICOMP FB VCOMP C3 R4 R5 R3 SENSE GND C4 C5 RS Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS8465-01 March 2013 www.richtek.com 1RT8465 Ordering Information Pin Configurations RT8465 (TOP VIEW) Package Type S : SOP-8 8 GND VCOMP 2 7 GATE SIN Lead Plating System 3 6 VCC ICOMP Z : ECO (Ecological Element with 4 SENSE 5 FB Halogen Free and Pb free) Note : SOP-8 Richtek products are : RoHS compliant and compatible with the current require- Marking Information ments of IPC/JEDEC J-STD-020. RT8465ZS : Product Number Suitable for use in SnPb or Pb-free soldering processes. RT8465 YMDNN : Date Code ZSYMDNN Functional Pin Description Pin No. Pin Name Pin Function 1 GND Ground. 2 GATE Gate Driver for External MOSFET Switch. 3 VCC Power Supply. For good bypass, place a ceramic capacitor near the VCC pin. Inductor Current Sense Input. The inductor current is sensed by a resistor between GND and SENSE pins. The sense pin signal is used as the saw tooth signal to the 4 SENSE PWM comparator. The comparator output will modulate the GATE turn-on duty to achieve the output voltage regulation. Output Voltage Sense Input. The Output voltage is sensed through an external resistive divider. The sensed voltage (which is tied to amplifier negative input) is 5 FB compared to an internal reference threshold at 1.2V (which is tied to amplifier positive input). Output of the Multiplier. To achieve high power factor, the voltage loop amplifier 6 ICOMP output signal is modulated with the sensed input voltage through the SIN pin by an internal multiplier. A compensation network between ICOMP and GND is needed. Input Power Voltage Sensing for PFC Function. An external resistor for input 7 SIN voltage sensing is connected to the power input. Output of the Internal Voltage Loop GM Amplifier. A compensation network 8 VCOMP between VCOMP and GND is needed. Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS8465-01 March 2013 2