UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 8-Pin Continuous Conduction Mode (CCM) PFC Controller FEATURES DESCRIPTION 1 • • • • • • • • • 8-pin Solution Reduces External Components Wide-Range Universal AC Input Voltage Fixed 65-kHz Operating Frequency Maximum Duty Cycle of 98% (typ.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 ELECTRICAL CHARACTERISTICS Unless otherwise noted, VCC=15 VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com ELECTRICAL CHARACTERISTICS (continued) Unless otherwise noted, VCC=15 VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 DEVICE INFORMATION SOIC PDIP Top View 1 GND GATE 8 2 ICOMP VCC 7 3 ISENSE VSENSE 6 VINS VCOMP 5 4 TERMINAL FUNCTIONS NAME PIN # GATE 8 GND 1 ICOMP 2 I/O O FUNCTION Gate drive: Integrated push-pull gate driver for one or more external power MOSFETs. Typical 2.0-A sink and 1.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 TYPICAL CHARACTERISTICS Unless otherwise noted, VCC = 15VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal. SUPPLY CURRENT vs BIAS SUPPLY VOLTAGE UVLO THRESHOLDS vs TEMPERATURE 4.0 12.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS (continued) Unless otherwise noted, VCC = 15VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 TYPICAL CHARACTERISTICS (continued) Unless otherwise noted, VCC = 15VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS (continued) Unless otherwise noted, VCC = 15VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal. MINIMUM OFF TIME vs TEMPERATURE 2.0 600 1.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 TYPICAL CHARACTERISTICS (continued) Unless otherwise noted, VCC = 15VDC, 0.1 µF from VCC to GND, -40°C ≤ TJ = TA ≤ 125°C. All voltages are with respect to GND. Currents are positive into and negative out of the specified terminal. GATE LOW VOLTAGE WITH DEVICE OFF vs TEMPERATURE 2.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Bias Supply The UCC28019A operates from an external bias supply. It is recommended that the device be powered from a regulated auxiliary supply. NOTE: This device is not intended to be used from a bootstrap bias supply.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Soft Start Soft Start controls the rate of rise of VCOMP in order to obtain a linear control of the increasing duty cycle as a function of time. VCOMP, the output of the voltage loop transconductance amplifier, is pulled low during UVLO, IBOP, and OLP (Open-Loop Protection)/STANDBY.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com System Protection System-level protection features help keep the converter within safe operating limits: VCC Under-Voltage Lockout (UVLO) During startup, Under-Voltage Lockout (UVLO) keeps the device in the off state until VCC rises above the 10.5-V enable threshold, VCCON.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Input Brown-Out Protection (IBOP) The sensed line-voltage input, VINS, provides a means for the designer to set the desired mains RMS voltage level at which the PFC pre-regulator should start-up, VACturnon, as well as the desired mains RMS level at which it should shut down, VACturnoff.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com The filter capacitor, CVINS, has two functions. First, to attenuate the voltage ripple to levels between the enable and brown-out threshold to prevent ripple on VINS from falsely triggering IBOP when the converter is operating at low line.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Output Under-Voltage Detection (UVD) and Enhanced Dynamic Response (EDR) During normal operation, small perturbations on the PFC output voltage rarely exceed 5% deviation and the normal voltage control loop gain drives the output back into regulation.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Over-Current Protection Inductor current is sensed by RISENSE, a low value resistor in the return path of input rectifier. The other side of the resistor is tied to the system ground. The voltage is sensed on the rectifier side of the sense resistor and is always negative.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Current Sense Resistor, RISENSE The current sense resistor, RISENSE, is sized using the minimum threshold value of Soft Over Current (SOC), VSOC(min) = 0.66 V.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Current Loop The overall system current loop consists of the current averaging amplifier stage, the pulse width modulator (PWM) stage, the external boost inductor stage and the external current sensing resistor.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Control Logic The output of the PWM comparator stage is conveyed to the GATE drive stage, subject to control by various protection functions incorporated into the device. The GATE output duty-cycle may be as high as 99%, but will always have a minimum off-time tOFF_min.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Non-Linear Gain Generation The voltage at VCOMP is used to set the current amplifier gain and the PWM ramp slope. This voltage is buffered internally and is then subject to modification by the SOC function, as discussed earlier.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 DESIGN EXAMPLE 350-W, Universal Input, 390-VDC Output, PFC Converter This example illustrates the design process and component selection for a continuous conduction mode power factor correction boost converter utilizing the UCC28019A.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com + + The following procedure refers to the schematic shown in Figure 28. Figure 28.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Current Calculations First, determine the maximum average output current, IOUT(max): I OUT (max) = I OUT (max) = POUT (max) VOUT (8) 350 W @ 0 .
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Input Capacitor Note that the UCC28019A is a continuous conduction mode controller and as such the inductor ripple current should be sized accordingly.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Boost Inductor The boost inductor, LBST, is selected after determining the maximum inductor peak current, IL_PEAK(max): I L _ PEAK (max) = I IN _ PEAK (max) + I L _ PEAK (max) = 6.39 A + I RIPPLE 2 (28) 1.28 A = 7.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Switching Element The conduction losses of the switch are estimated using the RDS(on) of the FET at 125°C , found in the FET data sheet, and the calculated drain to source RMS current, IDS_RMS: 2 PCOND = I DS _ RMS RDSon( 125C ) (39) RDSon( 125C ) = 0.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Sense Resistor To accommodate the gain of the internal non-linear power limit, RSENSE is sized such that it will trigger the soft over-current at 25% higher than the maximum peak inductor current using the minimum SOC threshold, VSOC, of ISENSE. RSENSE = RSENSE = VSOC I L _ PEAK (max) ´1.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Output Capacitor The output capacitor, COUT, is sized to meet holdup requirements of the converter.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Output Voltage Set Point For low power dissipation and minimal contribution to the voltage set point error, it is recommended to use 1 MΩ for the top voltage feedback divider resistor, RFB1. Multiple resistors in series are used due to the maximum allowable voltage across each.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Loop Compensation The selection of compensation components, for both the current loop and the voltage loop, is made easier by using the UCC28019A Design Calculator spreadsheet that can be found in the Tools section of the UCC28019A product folder on the Texas Instruments website.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 The individual loop factors, M1 which is the current loop gain factor, and M2 which is the voltage loop PWM ramp slope, are calculated using the following conditions: The M1 current loop gain factor: • if : 0 < VCOMP < 2 then : M 1 = 0 . 064 • (81) if : 2 ≤ VCOMP < 3 then : M 1 = 0.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com Verify that the product of the individual gain factors is approximately equal to the M1M2 factor determined above, if not, reselect VCOMP and recalculate M1M2. M 1 ´ M 2 = 0.484 ´ 0.764 0.37 V V = 0.37 ms ms (90) V V @ M 1M 2 = 0.
UCC28019A www.ti.com..................................................................................................................................................
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com The open loop of the voltage transfer function, GVL(f) contains the product of the voltage feedback gain, GFB, and the gain from the pulse width modulator to the power stage, GPWM_PS, which includes the pulse width modulator to power stage pole, fPWM_PS. The plotted result is shown in Figure 31.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 The voltage error amplifier is compensated with a zero, fZERO, at the fPWM_PS pole and a pole, fPOLE, placed at 20 Hz to reject high frequency noise and roll off the gain amplitude. The overall voltage loop crossover, fV, is desired to be at 10 Hz.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com The total closed loop transfer function, GVL_total, contains the combined stages and is plotted in Figure 32.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Brown Out Protection Select the top divider resistor into the VINS pin so as not to contribute excessive power loss. The extremely low bias current into VINS means the value of RVINS1 could be hundreds of megaOhms. For practical purposes, a value less than 10 MΩ is usually chosen.
UCC28019A SLUS828B – DECEMBER 2008 – REVISED APRIL 2009.................................................................................................................................................. www.ti.com The capacitor on VINS, CVINS, is selected so that it's discharge time is greater than the output capacitor hold up time. COUT was chosen to meet one-cycle hold-up time so CVINS will be chosen to meet 2.5 half-line cycles.
UCC28019A www.ti.com.................................................................................................................................................. SLUS828B – DECEMBER 2008 – REVISED APRIL 2009 Additional References These references, additional design tools, and links to additional references, including design software and models may be found on the web at www.power.ti.com under Technical Documents.
PACKAGE OPTION ADDENDUM www.ti.
PACKAGE MATERIALS INFORMATION www.ti.com 12-May-2009 TAPE AND REEL INFORMATION *All dimensions are nominal Device UCC28019ADR Package Package Pins Type Drawing SOIC D 8 SPQ Reel Reel Diameter Width (mm) W1 (mm) 2500 330.0 12.4 Pack Materials-Page 1 A0 (mm) B0 (mm) K0 (mm) P1 (mm) 6.4 5.2 2.1 8.0 W Pin1 (mm) Quadrant 12.
PACKAGE MATERIALS INFORMATION www.ti.com 12-May-2009 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) UCC28019ADR SOIC D 8 2500 340.5 338.1 20.
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