STEP-UP DC/DC CONVERTER
We recommend succeeding products
The R1205x Series are CMOS-based PWM control type step-up DC/DC converter ICs with low supply current.
Each of these ICs consists of an NMOS FET, a diode, an oscillator, a PWM comparator, a voltage reference unit, an error amplifier, a current limit circuit, an under voltage lockout circuit (UVLO), an over-voltage protection circuit (OVP), a soft-start circuit, a Maxduty limit circuit, and a thermal shutdown protection circuit. This step-up DC/DC converter can be easily built with a few external components such as a coil, a resistor, and a capacitor.
As the protection functions, the R1205x Series have a Lx peak current limit function, an over voltage protection (OVP) function, an under voltage lock out (UVLO) function and a thermal shutdown function.
The R1205x Series present the R1205x8xxA version that is optimized for the constant voltage power source, and the R1205x8xxB/C version that is optimized for driving the white LED with the constant current. The R1205x8xxB/C is an adjustable version that can change the LED brightness dynamically by using a 200Hz to 300kHz PWM signal toward the CE pin.
The R1205x Series are available in DFN1616-6B and TSOT-23-6 packages.
|Input Voltage Range||2.3V to 5.5V (R1205x8xxA)
1.8V to 5.5V (R1205x8xxB/C)
|Supply Current||Typ. 800µA|
|Standby Current||Max. 5µA|
|Feedback Voltage||1.0V±1.5% (R1205x8xxA)
|Oscillator Frequency||Typ. 1.2MHz|
|Maximum Duty Cycle||Typ. 91%|
|UVLO Function||Typ.2.0V (Hys.Typ.0.2V) (R1205x8xxA)
Typ.1.6V (Hys.Typ.0.1V) (R1205x8xxB/C)
|Lx Current Limit Function||Select from 350mA, 700mA|
|Over Voltage Protection||Typ. 25V|
|LED dimming control (R1205x8xxB/C)||by external PWM signal (Frequency 200Hz to 300kHz)|
|Thermal Protection Function||Typ.150ºC(Hys.Typ.50ºC)|
|Switch ON Resistance||Typ. 1.35Ω|
|Ceramic capacitors are recommended|
- ・Constant Voltage Power Source for portable equipment
- ・OLED power supply for portable equipment
- ・White LED Backlight for portable equipment
|Data Sheet||Flyer||Design Guide|
|Package Info.||Mark Info.||Quality Assurance Data|
All PDF files are less than 1MB unless otherwise stated.