UNISONIC TECHNOLOGIES CO., LTD UC4601 Preliminary CMOS IC PWM STEP-DOWN DC-DC CONTROLLER DESCRIPTION The UTC UC4601 is a PWM step-down DC/DC controller. It has a low supply current. The step-down DC/DC converter with low ripple, high efficiency performance is conveniently configured with additional external components, such as a power-transistor, an inductor, a diode and capacitors. The output voltage can be adjusted with external components. The UTC UC4601 contains a high precision band-gap voltage reference, a PWM control circuit, a soft-start circuit, a protection circuit, an oscillator, an error amplifier with built-in compensation network and input/output voltage detection circuits. The UTC UC4601 based DC/DC converter can performance well when maintaining stability, which is due to its built-in state-of-art control algorithm. Further, if the term of maximum duty cycle retains on a certain time, the embedded protection circuits restart the operation with soft-start and repeat until the maximum duty cycle condition is released. Finally, the internal UVLO function blocks potentially unstable output when the input voltage reaches the UVLO threshold or less. This is aiming at making this circuit standby for low power consumption. The UTC UC4601 can be applied in battery-powered equipment, hand-held communication equipment, cameras, video instruments such as VCRs, camcorders, household electrical appliances. FEATURES * 500kHZ oscillation frequency * Input voltage varies from 2.3V to 18V * Low temperature coefficient of output voltage: Typ. ±100ppm/°C * Internal soft-start and protection function * High efficiency up to 90% (TYP.) * High output voltage accuracy: ±2% * Standly current: 0.1μA (TYP.) * CMOS output capability ORDERING INFORMATION Ordering Number Lead Free Halogen Free UC4601L-AF5-R UC4601G-AF5-R Package Packing SOT-25 Tape Reel UC4601L - AF5 - R (1) Packing Type (1) R: Tape Reel (2) Package Type (2) AF5: SOT-25 (3) Lead Free (3) G: Halogen Free, L: Lead Free www.unisonic.com.tw Copyright © 2011 Unisonic Technologies Co., Ltd 1 of 4 QW-R502-494.c UC4601 Preliminary CMOS IC MARKING 4 5 UJ46 1 2 G: Halogen Free L : Lead Free 3 PIN CONFIGURATION PIN DESCRIPTION PIN NO 1 2 3 4 5 PIN NAME CE GND VFB EXT VIN DESCRIPTION Chip Enable. Active with “H” Ground Feedback Voltage External Transistor Driver Pin (CMOS output) Power input voltage UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 4 QW-R502-494.c UC4601 Preliminary CMOS IC ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT VIN Supply Voltage VIN 20 V Ext Pin Output Voltage VEXT -0.3 ~ VIN+0.3 V CE Pin Input Voltage VCE -0.3 ~ VIN+0.3 V VOUT/VFB Pin Input Voltage VOUT/VFB -0.3 ~ 6 V Ext Pin Output Current IEXT ±50 mA Power Dissipation PD +250 mW Operating Temperature TOPR -40 ~ +85 °C Storage Temperature TSTG -55 ~ +125 °C Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. OPERATING RANGE PARAMETER VIN Supply Voltage Ext Pin Output Voltage CE Pin Input Voltage VOUT/VFB Pin Input Voltage Ext Pin Output Current SYMBOL VIN VEXT VCE VOUT/VFB IEXT RATINGS 2.5 ~ 18 -0.3 ~ VIN+0.3 -0.3 ~ VIN+0.3 -0.3 ~ 5.5 ±50 UNIT V V V V mA ELECTRICAL CHARACTERISTICS (TOPR=25°C, unless otherwise specified) PARAMETER SYMBOL ADJUSTABLE OUTPUT VOLTAGE TYPE Operating Voltage VIN Feedback Voltage VFB Feedback Voltage Temperature ΔVFB/ΔT coefficient Supply Current IQ1 Shutdown Current IQ2 Oscillator Frequency fOSC Maximum Duty Cycle DMAX Minimum Duty Cycle DMIN EXT “H” Output Current IEXTH EXT “L” Output Current IEXTL CE “H” Output Current ICEH CE “L” Output Current ICEL CE “H” Input Voltage VCEH CE “L” Input Voltage VCEL UVLO Voltage VUVLO1 TEST CONDITIONS VIN=VCE=8V, VEXT=7.9V, VFB=3V VIN=VCE=8V, VEXT=0.1V, VFB=0V VIN=VCE=VOUT=18V VIN=VOUT=18V, VCE=0V VIN=8V, VFB=0V VIN=8V, VFB=0V VIN=VCE=2.5V≥1.5V, VFB=0V UVLO Release Voltage VUVLO2 VIN=VCE=1.5V≥2.5V, VFB=0V Delay Time by Soft-Start Delay Time by Protection TSST TPROT VIN=8V, ILOAD =10mA, VCE=0V≥2.5V VIN=VCE=2.5V, VFB=2.5V≥0V VIN=VCE=8V, ILOAD =350mA TYP MAX UNIT 2.3 0.98 1.00 18 1.02 V V -40°C <TOPR<85°C ±100 VIN=VCE=18V, VFB=2V VIN=18V, VCE=VFB=0V VIN=VCE=8V, ILOAD =350mA 40 0.1 500 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 400 100 20 -0.3 1.8 -17 30 0 0 1.75 2.0 5 5 VUVLO1 +0.1 10 15 ppm/°C 80 1 600 0.3 2.25 μA μA kHZ % % mA mA μA μA V V V 2.4 V 20 30 ms ms 0 -10 0.5 3 of 4 QW-R502-494.c UC4601 Preliminary CMOS IC TYPICAL APPLICATION CIRCUIT Adjustable Output Voltage Type. For example, Output Voltage=3.3V UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 4 QW-R502-494.c