The R1201N Series are CMOS-based PWM step-up DC/DC converters, which are optimized to drive white LEDs with constant current. R1201N includes a forward diode, an under-voltage lockout circuit (UVLO), and over-voltage protection circuit (OVP). By simply using an inductor, a resistor, and capacitors as external components, white LEDs can be driven with constant current and high efficiently. A diode is built-in; therefore it is possible to drive up to 5 serial LEDs without an external diode. The oscillator frequency can be selected from 1MHz or 1.2MHz. 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 (200Hz to 300kHz) to the CE pin.
The R1201N Series are CMOS-based PWM step-up DC/DC converters designed to drive white LEDs with constant current. The series includes a built-in forward diode and under-voltage lockout circuit (UVLO), allowing the drive of up to five serial LEDs without an external diode. Users can select the oscillator frequency between 1MHz or 1.2MHz, and adjust LED brightness by applying a PWM signal to the CE pin.
| Supply Current (Iop) Typ. | 500uA (1.2MHz) |
|---|---|
| Oscillator Frequency | 1MHz or 1.2MHz |
| Input Voltage Range (1A/3A Version) | -1.8V to 5.5V |
| Input Voltage Range (2A/4A Version) | 1.8V to 4.5V |
| UVLO Detect Voltage Typ. | 1.6V |
| Package Type | SOT-23-6 |
The converter is optimized to drive white LEDs using a constant current method.
Yes, because it includes a built-in diode that allows driving up to 5 serial LEDs.
The oscillator frequency can be selected from either 1MHz or 1.2MHz.
The typical maximum duty cycle is 91%.