www.fairchildsemi.com KA7552A/KA7553A SMPS Controller Features Description • Built-in drive circuits for direct connection power MOSFET (lO = ±1.5A) • Wide operating frequency range (5kHz ~ 600kHz) • Pulse by pulse over current limiting • Over load protection • On/off control by external trigger • Internal UVLO • Low standby current (typ. 90uA) • Soft start circuit The KA7552A/KA7553A are switching power control IC for wide operating frequency range. The internal circuits include pulse by pulse current limiting, protection, on/off control by external trigger, low standby current, soft start, and high current totempole output for driving a POWER MOSFET. Maximum duty of the KA7552A is 70% and the KA7553A is 46%. When duty is maximum, the input threshold voltage of pin2 & pin8 are not same in KA7552A and KA7553A. 8-DIP 1 Internal Block Diagram + _ 0.56 ~ 0.42V CS CT RT 8 7 1 VCC 10uA 6 OSC + - 7V UVLO BIAS (4V) OFF 3.6V 2.8V 4.3K + - 2.4V 1.9V 0.24V FB 5 OUTPUT PWM R _ + 2 + - O.C.P Q S 3 4 IS(+) GND Rev. 1.0.2 ©2004 Fairchild Semiconductor Corporation KA7552A/KA7553A Absolute Maximum Ratings Parameter Supply voltage Symbol Value Unit VCC 30 V IO ±1.5 A Input voltage at overcurrent detection pin VIN(IS) -0.3 to 4 V Input voltage at FB pin VIN(FB) 4 V Input current at CS pin IIN(CS) 2 mA PD 800 mW Output current Total power dissipation (Ta = 25°C) Operating temperature TOPR -25 to 85 °C Storage temperature range TSTG -65 to 150 °C Tj +125 °C Junction temperature Electrical Characteristics (VCC = 18V, FOSC = 135kHz, TA = 25°C, unless otherwise specified) Parameter Symbol Conditions Min. Typ. Max. Unit OSCILLATOR SECTION Initial accuracy FOSC CT = 360pF, TJ = 25°C 125 135 145 kHz Frequency variation 1 ∆F/∆V VCC = 10V to 30V - ±1 ±3 % ∆F/∆V TA = 25°C to 85°C - ±1.5 - % Frequency variation 2 (Note1) Ramp high voltage VRH CT = 360pF, TJ = 25°C 2.80 3.08 3.30 V Ramp low voltage VRL CT = 360pF, TJ = 25°C 0.6 0.9 1.2 V VPIN7, peak to peak 1.80 2.18 2.50 V Duty cycle = 0% 0.6 0.75 0.95 V VTH(FB1) (KA7552) Duty cycle = Dmax 1 2.1 2.3 2.6 V VTH(FB2) (KA7553) Duty cycle = Dmax 2 1.6 1.8 2.1 V Amplitude VOSC PULSE WIDTH MODULATION SECTION Input threshold voltage(pin2) Input threshold voltage(pin2)(Note1) Max. duty cycle Source current(pin2) VTH(FBD) D(Max1) (KA7552) - 66 70 74 % D(Max2) (KA7553) - 43 46 49 % ISOURCE(FB) VPIN2 = 0V -660 -800 -960 uA 0.21 0.27 V -300 -200 -100 uA OVERCURRENT LIMIT SECTION Input threshold voltage Source current(pin3) Deley time(Note1) - VTH(IS) ISOURCE(IS) VPIN3 = 0V TD - 0.24 - 150 - ns -15 -10 -5 uA 0.7 0.9 1.1 V SOFT START SECTION Charging current Input threshold voltage(pin8) Input threshold voltage(pin8)(Note1) ICHG VTH(CSO) VPIN8 = 0V - VTH(CS1) (KA7552) Duty cycle = Dmax 1 2.2 2.4 2.6 V VTH(CS2) (KA7553) Duty cycle = Dmax 2 1.7 1.9 2.1 V ISINK(CS) VPIN8 = 6V, VPIN2 = 1V 25 45 65 uA VTH(SD,CS) - 6.7 7.2 7.7 V VTH(SD,FB) - 2.6 2.8 3.1 V LATCH MODE SHUTDOWN CIRCUIT SECTION Sink current(pin8) Shutdown threshold voltage OVERLOAD SHUTDOWN SECTION Shutdown threshold voltage 2 KA7552A/KA7553A Electrical Characteristics (Continued) (VCC = 18V, FOSC = 135kHz, TA = 25°C, unless otherwise specified) Parameter Symbol Conditions Min. Typ. Max. Unit Start-up threshold voltage VTH(ST) - 15.5 16.0 16.5 V Minimum operating voltage VOPR(Min) - 8.20 8.70 9.20 V VHYS - 6.40 7.30 8.20 V VPIN8 = 0V -15 -10 -5 uA UNDER VOLTAGE LOCKOUT SECTION Hysteresis ON/OFF CONTROL SECTION Source current(pin8) ISOURCE(CS) On threshold voltage VTH(ON) VPIN8 : OFF->ON 0.45 0.56 0.70 V Off threshold voltage VTH(OFF) VPIN8 : ON -> OFF 0.30 0.42 0.55 V OUTPUT SECTION Low output voltage VOL IO = 100mA, VCC = 18V - 1.3 1.8 V High output voltage VOH IO = -100mA, VCC = 18V 16.0 16.5 18.0 V (Note1) TR No load - 50 - ns TF No load - 50 - ns Stand-by current ISB VCC = 14V - 90 150 uA Operating current ICC(OPR) VPIN2 = 0V - 9 15 mA Power supply current off ICC(OFF) VPIN8 = 0V - 1.1 1.8 mA Power supply current shutdown ICC(SD) VPIN8 = 7.6V - 1.1 1.8 mA Rise time (Note1) Fall time OVERALL Note : 1. These parameters, although guaranteed, are not 100% tested in production. 2. Recommend operating condition : - Vcc(min) = 12V - RT = 3.3kΩ ~ 10kΩ - Oscillation frequency = 5kHz ~ 600kHz - Soft start capacitor(CS) = 0.1uF ~ 1uF 3 KA7552A/KA7553A Mechanical Dimensions Package Dimensions in millimeters #5 1.524 ±0.10 0.060 ±0.004 #4 0.018 ±0.004 #8 2.54 0.100 9.60 MAX 0.378 #1 9.20 ±0.20 0.362 ±0.008 ( 6.40 ±0.20 0.252 ±0.008 0.46 ±0.10 0.79 ) 0.031 8-DIP 5.08 MAX 0.200 7.62 0.300 3.40 ±0.20 0.134 ±0.008 +0.10 0.25 –0.05 +0.004 0~15° 4 0.010 –0.002 3.30 ±0.30 0.130 ±0.012 0.33 MIN 0.013 KA7552A/KA7553A Ordering Information Product Number KA7552A KA7553A Package Operating Temperature 8-DIP -25 ~ +85°C 5 KA7552A/KA7553A DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 6/25/04 0.0m 001 Stock#DSxxxxxxxx 2003 Fairchild Semiconductor Corporation