ELM95xxxxECMOS PWM step-up DC/DC converter

ELM95xxxxE is CMOS PWM step-up DC/DC converter which consists of reference voltage source, error amplifier, oscillation circuit, start-up circuit, PWM control circuit, switching current limit circuit, switch transistor and output voltage setting resistor. For external parts, coil, diode and capacitor are possible choices; with external parts, 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. There are two switching frequency and maximum duty ratio available:(Switching frequency, Maximum duty ratio)=(55kHz, 60%) and (100kHz, 77%).

Output voltage range2.5V to 5.5V(by 0.1V)
Low voltage operationVin>=0.9V(No load)
Low power operation35μW(ELM9530AxE)
High efficiencyTyp.85%
High accuracy output voltage±2.5%
Constant switching frequencyTyp.55kHz(Type A), Typ.100kHz(Type B)
Output current(e.g.)100mA(Type B, Vin=1.5V, Vout=3.3V)
Small ripplesCeramic capacitor can be used for output capacitor.
Constant voltage source for battery-operated devices
Constant voltage source for cameras
Portable communications equipments
Local regulator

Absolute Maximum Ratings

Apply voltage to LX pinVlxVss-0.3 to 8.0V
Apply voltage to VOUT pinVoutVss-0.3 to 8.0V
Output current of LX pinIlx500mA
Power dissipationPd500 (SOT-89)
250 (SOT-23)
Operating temperatureTop-40 to +85°C
Storage temperatureTstg-55 to +125°C

Block diagram