ELM95xxD CMOS PWM step-up DC/DC converter ■General description ELM95xxD series is CMOS PWM step-up DC/DC converter which consists of reference voltage source, error amplifier, oscillation circuit, start-up circuit, PWM control circuit, switch transistor and output voltage setting resistor. For external parts, coil, diode and capacitor are possible choices; with external parts, ELM95 series can acquire constant output voltage higher than input voltage. The standard output voltages are 2.7V,3.0V,3.3V and 5.0V; ELM95 series can also be designed as semi-custom IC within the range of 2.5V to 5.5V by 0.1V step. With newly-developed PWM control circuit, ELM95 series is able to modulate switching time smoothly with constant frequency and consequently generates stable output with small ripples. ■Features ■Application • • • • • • • • • • Constant voltage source for batteryoperated devices • Constant voltage source for cameras • Portable communication equipments • Local regulator Output voltage range : 2.5V to 5.5V (by 0.1V) Low voltage operation : Vin≥0.98V (RL=30kΩ) Low power operation : 35μW (Typ. ELM9530D) High efficiency : Typ. 85% High output voltage accuracy : ±2.5% Output current (e.g.) : 10mA (When Vin=1.5V, Vout=3.0V) Constant output frequency : Typ. 55kHz Small ripples Package : SOT-89 ■Maximum absolute ratings Parameter Apply voltage to LX pin Apply voltage to VOUT pin Output current of LX pin Power dissipation Operating temperature Storage temperature Symbol Vlx Vout Ilx Pd Top Tstg Limit 12 12 200 300 -40 to +85 -55 to +125 Unit V V mA mW °C °C ■Selection guide ELM95xxD-x Symbol a, b Output voltage c Product version d Taping direction e.g.: 27: Vout=2.7V 30: Vout=3.0V 33: Vout=3.3V 50: Vout=5.0V D S : Refer to PKG file N : Refer to PKG file 5- 1 ELM95 x x D - x ↑ ↑ ↑ ↑ a b c d ELM95xxD CMOS PWM step-up DC/DC converter ■Pin configuration SOT-89 (TOP VIEW) Pin No. 1 2 3 ■Standard circuit Pin name VSS VOUT LX ■Block diagram 㪤㪘㪎㪉㪈 㪣㪯 㪧㪅㪮㪅㪤㪅 㪭㪦㪬㪫 㪉㪉㪇㱘㪟 㪭㫀㫅 㪣㪯 㪜㪣㪤㪐㪌㫏㫏㪛 㪭㪦㪬㪫 㪭㫆㫌㫋 㪂 㪭㪪㪪 㪋㪎㱘㪝 㪭㫉㪼㪽 㪪㫋㪸㫉㫋㪄㫌㫇 㪦㫊㪺㫀㫃㫃㪸㫋㫆㫉 㪭㪪㪪 ■Electrical characteristics Vout=2.7V (ELM9527D) Parameter Input voltage Starting voltage Holding voltage Current consumption Output voltage Output current of LX pin Leakage current of LX pin Oscillating frequency Maximum duty ratio Symbol Vin Vst Vhold Iss Vout Ilx Ilxl Fosc Duty L=220μH, D=MA721, C=47μF, Vss=0V, Top=25°C Condition Min. Typ. Max. Unit 10 V RL=27kΩ 0.98 V Iout=1mA 0.7 V Vin=1.5V 9.0 18.0 μA Iout=1mA, Vin=1.5V 2.63 2.70 2.77 V Vout=2.6V, Vlx=0.4V 70 mA Vout=Vlx=10V 1.0 μA Vout=2.6V 35 55 75 kHz Vout=2.6V 45 60 75 % Symbol Vin Vst Vhold Iss Vout Ilx Ilxl Fosc Duty L=220μH, D=MA721, C=47μF, Vss=0V, Top=25°C Condition Min. Typ. Max. Unit 10 V RL=30kΩ 0.98 V Iout=1mA 0.7 V Vin=1.5V 12.0 20.0 μA Iout=1mA, Vin=1.5V 2.92 3.00 3.08 V Vout=2.9V, Vlx=0.4V 80 mA Vout=Vlx=10V 1.0 μA Vout=2.9V 35 55 75 kHz Vout=2.9V 45 60 75 % Vout=3.0V (ELM9530D) Parameter Input voltage Starting voltage Holding voltage Current consumption Output voltage Output current of LX pin Leakage current of LX pin Oscillating frequency Maximum duty ratio 5- 2 ELM95xxD CMOS PWM step-up DC/DC converter Symbol Vin Vst Vhold Iss Vout Ilx Ilxl Fosc Duty L=220μH, D=MA721, C=47μF, Vss=0V, Top=25°C Condition Min. Typ. Max. Unit 10 V RL=33kΩ 0.98 V Iout=1mA 0.7 V Vin=1.5V 14.0 23.0 μA Iout=1mA, Vin=1.5V 3.21 3.30 3.39 V Vout=3.2V, Vlx=0.4V 80 mA Vout=Vlx=10V 1.0 μA Vout=3.2V 35 55 75 kHz Vout=3.2V 45 60 75 % Symbol Vin Vst Vhold Iss Vout Ilx Ilxl Fosc Duty L=220μH, D=MA721, C=47μF, Vss=0V, Top=25°C Condition Min. Typ. Max. Unit 10 V RL=50kΩ 0.98 V Iout=1mA 0.9 V Vin=3V 30.0 45.0 μA Iout=1mA, Vin=3V 4.87 5.00 5.13 V Vout=4.8V, Vlx=0.4V 110 mA Vout=Vlx=10V 1.0 μA Vout=4.8V 35 55 75 kHz Vout=4.8V 45 60 75 % Vout=3.3V (ELM9533D) Parameter Input voltage Starting voltage Holding voltage Current consumption Output voltage Output current of LX pin Leakage current of LX pin Oscillating frequency Maximum duty ratio Vout=5.0V (ELM9550D) Parameter Input voltage Starting voltage Holding voltage Current consumption Output voltage Output current of LX pin Leakage current of LX pin Oscillating frequency Maximum duty ratio ■Marking SOT-89 㪸 㪺 㪹 㪻 a : the integer digit of the output voltage Mark Vout Mark 2 2.*V 4 3 3.*V 5 Vout 4.*V 5.*V b : the decimal digit of the output voltage Mark Vout Mark 0 5 *.0V 1 .1V 6 * 2 7 *.2V 3 8 *.3V 4 9 *.4V Vout *.5V *.6V *.7V *.8V *.9V c : Assembly lot No. A to Z (excepted I, O, X) d : Assembly lot No. 0 to 9 5- 3 ELM95xxD CMOS PWM step-up DC/DC converter ■External parts To design DC/DC converter with ELM95 series, coil, diode, and capacitor are necessary. (Refer to standard circuit configuration.) 1) Coil When choosing choke coil, please select that whose core is not magnetically saturated, DC resistance is low, and which has sufficient margin for rated current. For ELM95 series, ELM recommends following coil. • CM-5/CM-5N (Sumida Electric Co., Ltd.) 2) Diode When choosing diode, please select that whose forward voltage is small, switching speed is high and which has sufficient margin for rated current. For ELM95 series, ELM recommends schottoky diodes. 3) Capacitor When choosing capacitor, please select that whose capacity is comparatively large and voltage limit is at least three times larger than rated output voltage of used ELM95 series. For ELM95 series, ELM recommends to use “Aluminum electrolytic capacitor”. When using capacitors such as “Tantalum capacitor” or “Laminated ceramic capacitor”, there may be cases that few hundred hertz wave motion will happen in output voltage wave form. Under such circumstances, ELM recommends connecting resistance (1.0Ω approx.) to capacitor serially as following. 㪈㪅㪇㱅 㪣㪯 㪜㪣㪤㪐㪌㫏㫏㪛 㪭㫆㫌㫋 㪂 㪭㪦㪬㪫 㪫㪸㫅㫋㪸㫃㫌㫄 㪚㫆㫅㪻㪼㫅㫊㪼㫉 㪭㪪㪪 ■Typical characteristics • Vout=2.7V (ELM9527D) (Top=25°C, L=220μH, D=MA721, C=47μF) EFFICIENCY-Vin Efficiency,VRp-p - Vin (Iout =1mA) RIPPLE VOLTAGE-Vin Vout - Vin 100 50 Vout (V) 3 Iout =1mA 2 3mA 10mA 1 0 1 Vin (V) 90 40 80 30 VRp-p RIPPLE VOLTAGE 70 60 50 2 5- 4 20 10 0 1 Vin (V) 2 0 RIPPLE VOLTAGE VRp-p (mV)(mA) EFFICIENCY Efficiency (%) (%) EFFICIENCY EFFICIENCY ELM95xxD CMOS PWM step-up DC/DC converter • Vout=3.0V (ELM9530D) (Top=25°C, L=220μH, D=MA721, C=47μF) EFFICIENCY-Vin Efficiency,VRp-p - Vin (Iout=1mA) RIPPLE VOLTAGE-Vin Vout - Vin 50 100 Vout (V) 3 Iout =1mA 2 3mA 10mA 1 0 1 Vin (V) 2 40 80 30 RIPPLEVRp-p VOLTAGE 70 20 10 60 50 3 • Vout=3.3V (ELM9533D) 90 0 1 2 Vin (V) 3 VRp-p (mV)(mA) RIPPLE VOLTAGE Efficiency (%) (%) EFFICIENCY Efficiency EFFICIENCY 0 (Top=25°C, L=220μH, D=MA721, C=47μF) EFFICIENCY-Vin Efficiency,VRp-p - Vin (Iout =1mA) RIPPLE VOLTAGE-Vin Vout - Vin 50 100 Vout (V) 3 Iout =1mA 2 3mA 10mA 1 0 1 Vin (V) 2 40 80 30 RIPPLEVRp-p VOLTAGE 70 20 10 60 50 3 • Vout=5.0V (ELM9550D) 90 0 1 Vin (V) 2 3 VRp-p (mV)(mA) RIPPLE VOLTAGE Efficiency (%) (%) EFFICIENCY EFFICIENCY Efficiency 0 (Top=25°C, L=220μH, D=MA721, C=47μF) EFFICIENCY-Vin Efficiency,VRp-p - Vin (Iout =1mA) RIPPLE VOLTAGE-Vin Vout - Vin 100 50 Vout (V) 5 Iout =1mA 4 3mA 10mA 3 0 1 Vin (V) 2 90 40 80 30 70 RIPPLEVRp-p VOLTAGE 20 60 10 50 3 5- 5 0 1 2 3 Vin (V) 4 5 0 VRp-p (mV)(mA) RIPPLE VOLTAGE EFFICIENCY Efficiency (%) Efficiency EFFICIENCY