YB1522

The YB1522 is a step-up DC-DC converter; with wide input voltage range from 3V to 16V, which operates as current source to drive up to 3S7P to 3S10P (V_IN at 3V to 5V). Series connecting of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The light intensity of these LEDs is proportional to the current passing through them. The YB1522 switches at a fixed frequency of ~930KHz, allowing the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space consideration applications.

The YB1522 can drive up to 3S10P white LEDs from a single Li-Ion battery. At automotive (5V/12V) applications with higher conversion efficiency. To control LED brightness, the LED current can be pulsed by applying a PWM (pulse width modulated) signal with a frequency range of 100Hz to 1KHz to the CTRL pin.

YB1522 has integrated Latched Over Voltage Protection that prevents damage to the device in case of a high impedance output due to faulty LED or open circuit caused by abnormal conditions.