R1210N301C Datasheet, PDF (2/18 Pages) RICOH electronics devices division – PWM Step-up DC/DC Converter

PWM Step-up DC/DC Converter
R1210N××1× Series
OUTLINE
The R1210N××1× Series are PWM step-up DC/DC Converter, with high accuracy, low supply current by CMOS
process.
Each of the R1210N××1× Series consists of an oscillator, a PWM circuit, a reference voltage unit, an error amplifier,
phase compensation circuit, resistors for voltage detection, a chip enable circuit. Further, includes a controller against
drastic load transient, a control transistor with low ON-Resistance, ‘LX switch’, and a protection circuit for LX switch
and an output voltage detector. R1210N××1A Series contain further a circuit for changeover oscillator frequency each.
A low ripple, high efficiency step-up DC/DC converter can be composed of this IC with only three external compo-
nents, or an inductor, a diode and a capacitor.
The R1210N Series can detect drastic change of output voltage with a circuit controller. The load transient re-
sponse is improved compared with current model, furthermore the R1210N××1A Series have another function, that is,
when the load current is small, oscillator frequency is decreased by a circuit for switching oscillator frequency from
TYP. 100kHz to 35kHz, therefore, supply current is reduced.
The built-in chip enable circuit can make the standby mode with ultra low quiescent current.
Since the package for these ICs is small SOT-23-5, high density mounting of the ICs on board is possible.
FEATURES
• External Components ................................................................. Only an inductor, a diode, and a capacitor
• Standby Current ......................................................................... TYP. 0µA
• Low Temperature-Drift Coefficient of Output Voltage.............. TYP. ±100ppm/°C
• Output Voltage............................................................................. Stepwise Setting with a step of 0.1V in the range of
2.2V to 6.0V (××1C/D)
2.2V to 3.5V (××1A)
• Two choices of Basic Oscillator Frequency................................ 100kHz (××1A/C), 180kHz (××1D)
• Small Package .............................................................................. SOT-23-5 (Mini-mold)
• High Efficiency ............................................................................ TYP. 88%
(VIN=Set Output Voltage×0.6 [V], IOUT=10mA)
• Low Ripple, Low Noise
• Built-in a driver transistor with low on-resistance
• Start-up Voltage........................................................................... MAX. 0.9V
• Basic Frequency change-over circuit (only for ××1A type)....... from TYP. 100kHz to 35kHz
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