Maxim Integrated Products MAX8901A and MAX8901B: Step-up dc/dc converters have 92% efficiency
Claiming 92% efficiency, the MAX8901A/MAX8901B step-up dc/dc converters drive a string of two or six white LEDs. Enabling 1-μF input capacitors and 0.1-μF output capacitors, the converters drive 1.5- to 4-in. LCDs in battery-operated devices, such as PDAs, GPS (global-positioning-system) devices, smartphones, and digital cameras. Features include a single input enabling the IC and controlling LED intensity and 0.1-μA power consumption in shutdown mode. With the LED current proportional to the PWM (pulse-width-modulation) duty cycle, the MAX8901A uses a direct-PWM input for regulating LED intensity. The MAX8901B uses single-wire, serial-pulse dimming, reducing LED intensity in 32 linear steps; the devices have a 24.75-mA full-scale LED current for serial-pulse dimming at 0.75-mA per step. Available in 2×2-mm TDFN-8 packages, the MAX8901A and MAX8901B cost $1.25 (1000) each.
Maxim Integrated Products, www.maxim-ic.com















