L6563A

L6563 L6563A Advanced transition-mode PFC controller General features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Transition-mode control of PFC pre-regulators Very precise adjustable output overvoltage protection Tracking boost function Protection against feedback loop failure (Latched shutdown) Interface for cascaded converter's PWM controller Input voltage feedforward (1/V2) Remote ON/OFF control Low (≤90µA) start-up current 5mA max. quiescent current 1.5% (@ TJ = 25°C) internal reference voltage -600/+800 mA totem pole gate driver with active pull-down during UVLO SO14 package SO-14 Applications PFC pre-regulators for: ■ ■ ■ HI-END AC-DC adapter/charger Desktop PC, server, WEB server IEC61000-3-2 OR JEIDA-MITI compliant SMPS, in excess of 250W Order code Part number L6563 L6563TR L6563A L6563ATR Package SO-14 SO-14 SO-14 SO-14 Packaging Tube Tape & Reel Tube Tape & Reel Block diagram IN V 1 TRACKING BOOST COM P 2 M U LT 3 Ideal diode V FF 5 1 / V2 T BO 6 1:1 CURRENT MIRROR 1:1 BUFFER MULTIPLIER LINE VOLTAGE FEEDFORW ARD + 2.5V V O LTA G E R E G U LA TO R V oltage references V bias (INTERNAL SUPPLY BUS) 4 1.7V + + Q V CC LEADING-EDGE BLANKING CS 3V from V FF 14 V CC R R1 GND 12 R2 U VLO C O M P AR A TO R + V RE F2 U V LO S INDUCTOR SATURATION DETECTION ( not in L6563A ) SAT Q 15 V 13 GD D river 11 ZCD 10 RUN + 1.4V 0.7V - S tarter O FF ZE R O C U R R E N T D E TE C TO R S TA R TE R + 0.2V 0.3V + P FC _O K 7 + - D IS AB LE 0.52V 0.62V ON/OFF CONTROL (BROWNOUT DETECTION) LATCH SAT 9 P W M _ S TO P 8 P W M _ LA TC H FE E D B A C K F A ILU R E D E TE C T IO N November 2006 Rev 3 2.5V Vbias 1/37 www.st.com 37 Contents L6563 - L6563A Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 1.2 Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 3 4 5 6 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Typical electrical performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 Overvoltage protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Feedback Failure Protection (FFP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Voltage Feedforward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 THD optimizer circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Tracking Boost function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Inductor saturation detection (L6563 only) . . . . . . . . . . . . . . . . . . . . . . . . 26 Power management/housekeeping functions . . . . . . . . . . . . . . . . . . . . . . 27 Summary of L6563/A idle states . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 7 8 9 Application examples and ideas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 2/37 L6563 - L6563A Description 1 Description The device is a current-mode PFC controller operating in Transition Mode (TM). Based on the core of a standard TM PFC controller, it offers improved performance and additional functions. The highly linear multiplier, along with a special correction circuit that reduces crossover distortion of the mains current, allows wide-range-mains operation with an extremely low THD even over a large load range. The output voltage is controlled by means of a voltage-mode error amplifier and a precise (1.5% @TJ = 25°C) internal voltage reference. The stability of the loop and the transient response to sudden mains voltage changes are improved by the voltage feedforward function (1/V2 correction). Additionally, the IC provides the option for tracking boost operation (where the output voltage is changed tracking the mains voltage). The device features extremely low consumption (≤90 µA before start-up and ≤5 mA running). An interface with the PWM controller of the DC-DC converter supplied by the PFC preregulator is provided: the purpose is to stop the operation of the converter in case of anomalous conditions for the PFC stage (feedback loop failure, boost inductor's core saturation) and to disable the PFC stage in case of light load for the DC-DC converter, so as to make it easier to comply with energy saving norms (Blue Angel, EnergyStar, Energy2000, etc.). The device includes disable functions suitable for remote ON/OFF control both in systems where the PFC pre-regulator works as a master and in those where it works as a slave. In addition to an effective two-step OVP that handles normal operation overvoltages, the IC provides also a protection against feedback loop failures or erroneous output voltage setting. Figure 1. Typical system block diagram 3/37 Description L6563 - L6563A 1.1 Pin connection Figure 2. Pin connection (top view) INV COMP MULT CS VFF TBO PFC_OK 1 2 3 4 5 6 7 14 13 12 11 10 9 8 Vcc GD GND ZCD RUN PWM_STOP PWM_LATCH 1.2 Pin description Table 1. Pin description Pin N° Name Description Inverting input of the error amplifier. The information on the output voltage of the PFC preregulator is fed into the pin through a resistor divider. The pin normally features high impedance but, if the tracking boost function is used, an internal current generator programmed by TBO (pin 6) is activated. It sinks current from the pin to change the output voltage so that it tracks the mains voltage. Output of the error amplifier. A compensation network is placed between this pin and INV (pin 1) to achieve stability of the voltage control loop and ensure high power factor and low THD. Main input to the multiplier. This pin is connected to the rectified mains voltage via a resistor divider and provides the sinusoidal reference to the current loop. The voltage on this pin is used also to derive the information on the RMS mains voltage. Input to the PWM comparator. The current flowing in the MOSFET is sensed through a resistor, the resulting voltage is applied to this pin and compared with an internal reference to determine MOSFET’s turn-off. A second comparison level at 1.7V detects abnormal currents (e.g. due to boost inductor saturation) and, on this occurrence, shuts down the IC, reduces its consumption almost to the start-up level and asserts PWM_LATCH (pin 8) high. This function is not present in the L6563A. Second input to the multiplier for 1/V2 function. A capacitor and a parallel resistor must be connected from the pin to GND. They complete the internal peak-holding circuit that derives the information on the RMS mains voltage. The voltage at this pin, a DC level equal to the peak voltage at pin MULT (pin 3), compensates the control loop gain dependence on the mains voltage. Never connect the pin directly to GND. 1 INV 2 COMP 3 MULT 4 CS 5 VFF 4/37 L6563 - L6563A Table 1. Pin description (continued) Pin N° Name Description Description 1 INV Inverting input of the error amplifier. The information on the output voltage of the PFC preregulator is fed into the pin through a resistor divider. The pin normally features high impedance but, if the tracking boost function is used, an internal current generator programmed by TBO (pin 6) is activated. It sinks current from the pin to change the output voltage so that it tracks the mains voltage. Tracking Boost function. This pin provides a buffered VFF voltage. A resistor connected between this pin and GND defines a current that is sunk from pin INV (pin 1). In this way, the output voltage is changed proportionally to the mains voltage (tracking boost). If this function is not used leave this pin open. PFC pre-regulator output voltage monitoring/disable function. This pin senses the output voltage of the PFC pre-regulator through a resistor divider and is used for protection purposes. If the voltage at the pin exceeds 2.5V the IC is shut down, its consumption goes almost to the start-up level and this condition is latched. PWM_LATCH pin is asserted high. Normal operation can be resumed only by cycling the Vcc. This function is used for protection in case the feedback loop fails. If the voltage on this pin is brought below 0.2V the IC is shut down and its consumption is considerably reduced. To restart the IC the voltage on the pin must go above 0.26V. If these functions are not needed, tie the pin to a voltage between 0.26 and 2.5 V. 6 TBO 7 PFC_OK 8 Output pin for fault signaling. During normal operation this pin features high impedance. If either a voltage above 2.5V at PFC_OK (pin 7) or a voltage above 1.7V on CS (pin 4) of PWM_LATCH L6563A is detected the pin is asserted high. Normally, this pin is used to stop the operation of the DC-DC converter supplied by the PFC pre-regulator by invoking a latched disable of its PWM controller. If not used, the pin will be left floating. Output pin for fault signaling. During normal operation this pin features high impedance. If the IC is disabled by a voltage below 0.5V on RUN (pin 10) the voltage at the pin is pulled PWM_STOP to ground. Normally, this pin is used to temporarily stop the operation of the DC-DC converter supplied by the PFC pre-regulator by disabling its PWM controller. If not used, the pin will be left floating. Remote ON/OFF control. A voltage below 0.52V shuts down (not latched) the IC and brings its consumption to a considerably lower level. PWM_STOP is asserted low. The IC restarts as the voltage at the pin goes above 0.6V. Connect this pin to VFF (pin 5) either directly or through a resistor divider to use this function as brownout (AC mains undervoltage) protection, tie to INV (pin 1) if the function is not used. Boost inductor’s demagnetization sensing input for transition-mode operation. A negativegoing edge triggers MOSFET’s turn-on. Ground. Current return for both the signal part of the IC and the gate driver. Gate driver output. The totem pole output stage is able to drive power MOSFET’s and IGBT’s with a peak current of 600 mA source and 800 mA sink. The high-level voltage of this pin is clamped at about 12V to avoid excessive gate voltages. Supply Voltage of both the signal part of the IC and the gate driver. 9 10 RUN 11 12 13 14 ZCD GND GD VCC 5/37 Absolute maximum ratings L6563 - L6563A 2 Absolute maximum ratings Table 2. Absolute maximum ratings Symbol VCC ----IPWM_STOP IZCD Ptot TJ TSTG Pin 14 Parameter IC supply voltage (Icc = 20mA) Value self-limited -0.3 to 8 Self-limited 3 -10 (source) 10 (sink) 0.75 -25 to 150 -55 to 150 Unit V V V mA mA W °C °C 2, 4 to 6, 8 Analog inputs & outputs to 10 1, 3, 7 10 11 Max. pin voltage (Ipin = 1 mA) Max. sink current Zero current detector max. current Power dissipation @TA = 50°C Junction temperature operating range Storage temperature 3 Thermal data Table 3. Thermal data Symbol RthJA Parameter Maximum thermal resistance junction-ambient Value 120 Unit ° C/W 6/37 L6563 - L6563A Electrical characteristics 4 Electrical characteristics Table 4. Electrical characteristics ( -25°C < TJ < +125°C, VCC = 12V, Co = 1nF between pin GD and GND, CFF =1µF between pin VFF and GND; unless otherwise specified) Symbol Supply voltage Vcc VccOn VccOff Hys VZ Operating range Turn-on threshold Turn-off threshold Hysteresis Zener Voltage Icc = 20 mA After turn-on (1) (1) 10.3 11 8.7 2.3 22 25 12 9.5 22 13 10.3 2.7 28 V V V V V Parameter Test condition Min Typ Max Unit Supply current Istart-up Iq ICC Start-up current Quiescent current Before turn-on, Vcc=10V After turn-on 50 3 3.8 180 1.5 2 90 5 5.5 250 2.2 3 µA mA mA µA mA mA Operating supply current @ 70kHz Latched by PFC_OK>Vthl or Vcs>VCSdis Disabled by PFC_OK