Linear Integrated Circuit CURRENT− −MODE PWM CONTROLLER KA3842A KA3842AM PIN CONNECTION The KA3842A KA3842AM are fixe frequency current-mode PWM controller. They are specially designed for OFF−Line and DC−to−DC converter applications with minimal external components. These integrated circuits feature a trimmed oscillator for precise duty cycle control, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totempole output ideally suited for driving a power MOSFET. Protection circuity includes built under−voltage lockout and current limiting. The KA3842A,KA3842AM have UVLO thresholds of 16 V(on) and 10 V (off). The KA3842A ,KA384AM can operate within 100% duty cycle The KA3842A has been proven in applications using the same external components as Motorola's parts,among others .The KA3842AM has been optimized for compatibility with Samsung's parts Many applications can use either The KA3842A KA3842AM have Start-Up Current 0,45 mA KA3842A or KA3842AM SO-8 DIP-8 FEATURES • • • • ordering information Low Start-Up Current Maximum Duty Cycle U/V Lockout With Hysteresis Operating Freguency Up To 500khz Device KA3842AM KA3842AMM KA3842AN KA3842AMN BLOCK DIAGRAM Package SO-8 SO-8 DIP-8 DIP-8 Operating temperature 0 to +700C " " " Absolute Maximum Ratings Characteristic Supply Voltage Output Current Analog Inputs Error Amp Output Sink Current Power Dissipation (TA=250C) Wing Shing Computer Components Co., (H.K.)Ltd. Homepage: http://www.wingshing.com Symbol VCC IO Value 30 ±1 Unit V A VI −0.3 to VCC 10 1 mA W ISINK (E.A) PO V Tel:(852)2341 9276 Fax:(852)2797 8153 E-mail: [email protected] 1 KA3842A/KA3842AM Electrical characteristics (*VCC=15V, RT=10kΩ Ω , CT=3.3nF, TA=00C to +700C, unless otherwise specified) Characteristics Reference Section Reference Output Voltege Symbol VREF Line Regulation ∆VREF Load Regulation ∆VREF ISC Short Circit Output Current Oscillator Section Oscillation Freguency f Test Condition V 12V ≤ VCC ≤ 25 V 20 mV 1 mA ≤ IREF ≤ 20mA 6.0 25 -100 -180 mA 52 57 KHz 0.05 1.0 % TA = 25°C 47 TJ = 25°C Input Voltage Open Loop Voltage Gain VI(E.A) GVO V1 = 2.5V Power Supply Rejection Ratio PSRR 12V ≤ VCC ≤ 25 V V2 = 2.7V, V1 = 1.1V V2 = 2.3V, V1 = 5V Current Sense Section Gain Maximum Input Signal Power Supply Rejection Ratio 12V ≤ VCC ≤ 25 V 1.6 IBIAS ISOURCE VOH VOL GV VI(MAX) PSRR Input Bias Current IBIAS Output Section Low Output Voltage VOL High Output Voltage VOH Unit 5.1 V(OSC) ISINK Max 5.0 ∆f/∆VCCF Low Output Voltage 4.9 Typ 6.0 TJ = 25°C, IREF = 1 mA Frequency Change with Voltage Oscillator Amplitude Error Amplifier Section Input Bias Current Output Sink Current Output Source Current High Output Voltage Min 2V ≤ V0 ≤ 4V V2 = 2.3V, RL = 15KΩ to GND -0.1 -2 2.42 65 2.5 90 2.58 60 70 2 -0.5 5.0 7 -1.0 6.0 V2 = 2.7V, RL = 15KΩ to PIN 8 (Note 1 & 2) V1 = 5V (Note1) 2.85 0.9 12V ≤ VCC ≤ 25 V (Note 1) ISINK ISINK ISINK ISINK = = = = 20 mA 200 mA 20 mA 200 mA Vp-p µA V dB mA mA V 0.8 1.1 3.0 1.0 70 3.15 1.1 V/V V dB -3.0 -10 µA 0.4 2.2 V 150 nS Rise Time tR TJ = 25°C, CL = 1nF (Note 3) 0.08 1.4 13.5 13.0 45 Fall Time tF TJ = 25°C, CL = 1nF (Note 3) 35 150 14.5 16.0 17.5 V VOPR(min) 8.5 10 11.5 V D(MAX) 95 97 100 13 12 Under− −Voltage Lockout Section Start Theshold VTH(ST) Min. Operating Voltage (After Turn On) PWM Section Max. Duty Cycle % Min. Duty Cycle Total Standby Current Start−Up Current Operating Supply Current Zener Voltage D(MAX) 0 IST ICC (OPR) VZ V3 = V2 = 0V 30 0.17 0.3 14 38 17 * Adjust VCC above the start threshold before setting at 15V Note 1: Parameter measured at trip point of lath with V2=0 Note 2: Gain defined as A=∆V1/∆V3 ; 0 ≤ V3 ≤ 0.8V Note 3: These parameters, although guaranteed, are not 100% tested in production. 2 mA V KA3842A/KA3842AM Pad Location Chip size: 2.38 x 1.63 mm Pad N 1 2 3 4 Coordinates µm X Y 90 110 1050 110 1310 110 2000 150 3 Pad N 5 6 Coordinates µm X Y 1680 1450 1310 1410 7 8 815 460 1410 1390 KA3842A/KA3842AM mm DIM. MIN. TYP. A a1 inch MAX. MIN. TYP. 1.75 0.1 0.25 a2 0.069 0.004 0.010 0.065 1.65 a3 0.65 0.85 0.026 0.033 b 0.35 0.48 0.014 0.019 b1 0.19 0.25 0.007 0.010 C 0.25 0.5 0.010 0.020 c1 45° (typ.) D (1) 4.8 5.0 0.189 0.197 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 3.81 0.150 F (1) 3.8 4.0 0.15 L 0.4 1.27 0.016 M S OUTLINE AND MECHANICAL DATA MAX. 0.6 KA3842AM KA3842AMM 0.157 0.050 SO8 0.024 8 ° (max.) (1) D and F do not include mold flash or protrusions. Mold flash or potrusions shall not exceed 0.15mm (.006inch). 4 KA3842A/KA3842AM 8 NOTES: 1. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 2. PACKAGE CONTOUR OPTIONAL (ROUND OR SQUARE CORNERS). 3. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 5 –B– 1 4 DIM A B C D F G H J K L M N F –A– NOTE 2 L C J –T– N SEATING PLANE D H M K G 0.13 (0.005) M T A M B M KA3842AN KA3842AMN Attention: M=10 o 5 MILLIMETERS MIN MAX 9.40 10.16 6.10 6.60 3.94 4.45 0.38 0.51 1.02 1.78 2.54 BSC 0.76 1.27 0.20 0.30 2.92 3.43 7.62 BSC ––– 10_ 0.76 1.01 INCHES MIN MAX 0.370 0.400 0.240 0.260 0.155 0.175 0.015 0.020 0.040 0.070 0.100 BSC 0.030 0.050 0.008 0.012 0.115 0.135 0.300 BSC ––– 10_ 0.030 0.040