UNISONIC TECHNOLOGIES CO., LTD UC3500 CMOS IC HIGH EFFICIENCY VFM CONTROLLED STEP-UP DC/DC CONVERTER DESCRIPTION The UTC UC3500 Step-up DC/DC converters are optimized for applications that prioritize high efficiency and high frequency. The efficiency is greatly improved by utilizing an internal VFM controlled scheme that switches with fixed frequency and is adjustable up to more than 150 KHz depending on the load. The UTC UC3500 requires only three external components to realize the conversion from the battery voltage to the selected output voltage in the range of 2.5V ~ 5.5V. The start-up voltage of UTC UC3500 is guaranteed at 0.8V and the device is operating down to 0.5V. The Output current is guaranteed up to 150mA, while quiescent current is only 18μA. FEATURES * 0.8V start-up voltage * 0.5V hold-on voltage * Output current up to 150mA * Low supply current of 18μA * Wide output voltage range of 2.5V~5.5V * Output voltage accuracy ±2% * High efficiency up to 88% * Low profile and minimum external components ORDERING INFORMATION Ordering Number Lead Free Halogen Free UC3500L-xx-AB3-R UC3500G-xx-AB3-R UC3500L-xx-AE3-R UC3500G-xx-AE3-R UC3500L-xx-AF5-R UC3500G-xx-AF5-R www.unisonic.com.tw Copyright © 2009 Unisonic Technologies Co., Ltd Package Packing SOT-89 SOT-23 SOT-25 Tape Reel Tape Reel Tape Reel 1 of 12 QW-R502-072,D UC3500 CMOS IC MARKING INFORMATION PACKAGE VOLTAGE CODE MARKING 3 SOT-25 2 1 U3XX Voltage Code 4 25:2.5V 27:2.7V 28:2.8V 30:3.0V 33:3.3V 36:3.6V 40:4.0V 50:5.0V SOT-23 5 3 U3XX Voltage Code 2 L: Lead Free G: Halogen Free 1 XX Date Code UC3500 SOT-89 1 L: Lead Free G: Halogen Free 2 Voltage Code L: Lead Free G: Halogen Free 3 PIN CONFIGURATION SOT-25 SOT-23 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw SOT-89 2 of 12 QW-R502-072.D UC3500 CMOS IC BLOCK DIAGRAM OUT OUT LX OSCILLATOR ERROR AMPLIFIER VFM CONTROL VREF VIX LIMITER GND UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 12 QW-R502-072.D UC3500 CMOS IC ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT Output Voltage VOUT 7 V Input Voltage VIN 7 V LX Pin Voltage VLX 7 V LX Pin Output Current ILX Internally limited Power Dissipation at 25°С 160 mW SOT-23/SOT-25 PD Derating Rate Ta>25°С 1.6 °С/mW Operating Junction Temperature TOPR -25 ~ +85 °С Storage Temperature TSTG -65 ~ +150 °С 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. ELECTRICAL CHARACTERISTICS (Ta = 25°С, unless otherwise specified.) UC3500-2.5V (VIN = 1.4V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η UC3500-2.7V (VIN = 1.6V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 2.8V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 2.4 TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 3.0V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 2.6 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 0.4 0.3 0.4 0.3 TYP 2.5 0.7 0.8 0.6 0.5 18 760 0.1 150 75 81 83 82 MAX 2.6 1.1 1.2 TYP 2.7 0.7 0.8 0.6 0.5 18 760 0.1 150 75 82 83 82 MAX 2.8 1.1 1.2 0.3 0.3 UNIT V V V V V µA mΩ µA KHz % % % % UNIT V V V V V µA mΩ µA KHz % % % % 4 of 12 QW-R502-072.D UC3500 CMOS IC ELECTRICAL CHARACTERISTICS(Cont.) UC3500-2.8V (VIN = 1.7V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η UC3500-3.0V (VIN = 1.8V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η UC3500-3.3V (VIN = 2.0V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 3.1V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 2.7 TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 3.3V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 2.9 TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 3.6V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 3.2 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 0.4 0.3 0.4 0.3 0.4 0.3 TYP 2.8 0.7 0.8 0.6 0.5 18 760 0.1 150 75 82 83 82 MAX 2.9 1.1 1.2 TYP 3 0.7 0.8 0.6 0.5 18 750 0.1 150 75 82 84 82 MAX 3.1 1.1 1.2 TYP 3.3 0.7 0.8 0.6 0.5 18 750 0.1 150 75 83 85 84 MAX 3.4 1.1 1.2 0.3 0.3 0.3 UNIT V V V V V µA mΩ µA KHz % % % % UNIT V V V V V µA mΩ µA KHz % % % % UNIT V V V V V µA mΩ µA KHz % % % % 5 of 12 QW-R502-072.D UC3500 CMOS IC ELECTRICAL CHARACTERISTICS(Cont.) UC3500-3.6V (VIN =2.2V) PARAMETER Output Voltage SYMBOL VOUT TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 3.9V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 3.49 TEST CONDITIONS IOUT = 10mA IOUT = 0 IOUT = 1mA IOUT = 0 IOUT = 1mA IOUT = 0 ILX = 100mA VLX = 4V, VOUT = 4.3V IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 50mA IOUT = 100mA MIN 3.88 TEST CONDITIONS IOUT = 10mA IOUT = 0 Start-up Voltage (VIN-VF) (Note) VSTART IOUT = 1mA IOUT = 0 Hold-on Voltage VHOLD IOUT = 1mA Supply Current ISUPPLY IOUT = 0 Internal Switch RDS(ON) RLX ILX = 100mA Internal Leakage Current ILX(LEAK) VLX = 4V, VOUT = 5.3V Maximum Oscillator Frequency fOSC IOUT = 10mA Oscillator Duty Cycle Dty IOUT = 10mA IOUT = 10mA Efficiency η IOUT = 50mA IOUT = 100mA Note: VF references to the forward voltage of the diode. MIN 4.85 Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η UC3500-4.0V (VIN =2.4V) PARAMETER Output Voltage SYMBOL VOUT Start-up Voltage (VIN-VF) (Note) VSTART Hold-on Voltage VHOLD Supply Current Internal Switch RDS(ON) Internal Leakage Current Maximum Oscillator Frequency Oscillator Duty Cycle Efficiency ISUPPLY RLX ILX(LEAK) fOSC Dty η UC3500-5.0V (VIN = 3.0V) PARAMETER Output Voltage SYMBOL VOUT UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 0.4 0.3 0.4 0.3 0.4 0.3 TYP 3.6 0.7 0.8 0.6 0.5 18 750 0.1 150 75 84 86 85 MAX 3.71 1.1 1.2 TYP 4.0 0.7 0.8 0.6 0.5 19 740 0.1 150 75 85 87 85 MAX 4.12 1.1 1.2 TYP 5.0 0.7 0.8 0.6 0.5 19 730 0.1 150 75 86 88 85 MAX 5.15 1.1 1.2 0.3 0.3 0.3 UNIT V V V V V µA mΩ µA KHz % % % % UNIT V V V V V µA mΩ µA KHz % % % % UNIT V V V V V µA mΩ µA KHz % % % % 6 of 12 QW-R502-072.D UC3500 CMOS IC PRINCIPLE OF OPERATION The UTC UC3500 consists of a Band-Gap reference voltage source, error amplifier, VFM control logic core, oscillator, VLX limiter amplifier, N-channel MOSFET switching transistor and output voltage divider network. The device compares the Band-Gap reference voltage with the feedback voltage from the output through divider network. In TON phase, the energy is transferred from the battery to the inductor. The switch is turned off after a maximum on time set to 2.5µs. In TOFF phase, the energy stored in the inductor is transferred to the load. This process is continuously performed to ensure stable output voltage. Until the output voltage reaches the expected value. Therefore, in case of light load, the device works in PFM mode. In heavy load condition, the device works in continuous mode, the frequency range up to a maximum 150 KHz set by the built in oscillator. In over current conditions, the Ton time is shorted; the switching frequency will be higher than 150 KHz. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 12 QW-R502-072.D UC3500 TYPICAL APPLICATION CIRCUIT RECONMMENDED COMPONENTS L D CIN COUT CMOS IC ：47μH (Sunida CD54 Fosc＝500kHz) ：MA737, or MBRM110L ：10V 4.7μF (Tantalum) ：16V 47μF (Tantalum) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 8 of 12 QW-R502-072.D UC3500 CMOS IC TYPICAL CHARACTERISTICS UC3500-2.5V Output Waveform of LX Output Waveform of LX 4 4 3 3 2 2 1 1 0 0 3 2 1 0 2 1 0 50 50 0 0 -50 3 -50 0 25 50 75 100 125 150 175 200 225 250 Time(µs) IOUT=1mA 0 25 50 75 100 125 150 175 200 225 250 Time(ms) IOUT=10mA Output Waveform of LX Under Maximum Frenquency 4 3 2 1 0 -1 0 5 10 15 Time(µs) 25 20 focs=166kHz, Dty:83% UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 9 of 12 QW-R502-072.D UC3500 CMOS IC TYPICAL CHARACTERISTICS(Cont.) UC3500-2.7V Output Waveform of LX Output Waveform of LX 4 4 3 3 2 2 1 1 0 0 3 2 1 0 2 1 0 50 50 0 0 -50 3 -50 0 25 50 75 100 125 150 175 200 225 250 Time(µs) IOUT=1mA 0 25 50 75 100 125 150 175 200 225 250 Time(ms) IOUT=10mA Output Waveform of LX Under Maximum Frenquency 4 3 2 1 0 -1 0 5 10 15 Time(µs) 25 20 focs=166kHz, Dty:83% UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 10 of 12 QW-R502-072.D UC3500 CMOS IC TYPICAL CHARACTERISTICS(Cont.) UC3500-3.3V Output Waveform of LX Output Waveform of LX 4 4 3 3 2 2 1 1 0 0 3 2 1 0 2 1 0 50 50 0 0 -50 3 -50 0 25 50 75 100 125 150 175 200 225 250 IOUT=1mA 0 25 50 75 100 125 150 175 200 225 250 Time(ms) IOUT=10mA Output Waveform of LX(V) Time(µs) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 11 of 12 QW-R502-072.D UC3500 CMOS IC 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 12 of 12 QW-R502-072.D