R1208K Series

PWM Low Supply Current Step-up DC/DC Converter

Data Sheet
Data Sheet

The R1208x is a low supply current CMOS-based PWM control step-up DC/DC converter. Internally, a single converter consists of an NMOS FET, 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 thermal shutdown protection circuit and current drivers for four white LED channels.

By simply using an inductor, a resistor, capacitors and a diode, white LEDs can be driven with constant current and high efficiency. The LED current can be determined by the value of current setting resistor. The brightness of the LEDs can be adjusted quickly by applying a PWM signal (200 Hz to 300 kHz) to the CE pin.

Protection circuits included in the R1208x are a current limit circuit which limits the LX peak current, an UVLO circuit which prevents the malfunction of the device at low input voltage, an OVP circuit which monitors the excess output voltage and a thermal shutdown protection circuit which detects the overheating of the device and stops the operation to protect the device from damage.

The R1208x is offered in 12-pin DFN(PLP)2730-12 package.

Input Voltage Range 2.7 V to 22 V
Supply Current Typ. 600µA
Standby Current Typ. 1.5µA
Lx Current Limit Typ. 2 A
Overvoltage Protection (OVP) Typ. 23V / 33V / 43.5V
Oscillator Frequency Typ. 750kHz / 450kHz
Maximum Duty Cycle 95% (750kHz) / 97% (450kHz)
Nch MOSFET ON Resistance Typ. 0.28Ω
Undervoltage Lockout (UVLO) Typ. 2.4V
Thermal Shutdown Typ. 150°C
LED Dimming Control By sending a PWM signal (200Hz to 300kHz) to the CE pin
Package DFN(PLP)2730-12
  • LED backlight driver for LCD displays for portable equipment
  • LED backlight driver for LCD displays for Tablets and Note PCs.

Data Sheet Flyer Design Guide Package Info. Quality Assurance Data
R1208K Series to be prepared to be prepared DFN(PLP)2730-12 to be prepared

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