LTC3562 Datasheet | Linear Technology

I2C Quad Synchronous Step-Down DC/DC Regulator 2 × 600m A, 2 × 400m A Features DESCRIPTION n Four Independent I2C Controllable Step-Down Regulators (2 × 600m A, 2 × 400m A) n Two I2C Programmable Feedback Voltage Regulators (R600A, R400A): VFB 425m V to 800m V n Two I2C Programmable Output Voltage Regulators (R600B, R400B): VOUT 600m V to 3.775V n Programmable Modes: Pulse Skip, LDO, Burst Mode,® Forced Burst Mode Operation n Quiescent Current < 100μA (All Regulators Enabled in LDO Mode) n Fixed 2.25MHz Switching Frequency (Pulse Skip Mode) n Slew Limiting Reduces Switching Noise n Power-On Reset Output for Regulator R600A n Small, Thermally Enhanced, 20-Lead 3mm × 3mm QFN Package APPLICATIONS n Miscellaneous Handheld Applications with Multiple Supply Rails n Personal Information Appliances n Wireless and DSL Modems n Digital Still Cameras n MP3 Players n Portable Instruments The LTC®3562 is a quad high efficiency monolithic synchronous step-down regulator with an I2C interface. Two regulators are externally adjustable and can have their feedback voltages programmed between 425m V and 800m V in 25m V steps (Type A). The other two regulators are fixed output regulators whose output voltages can be programmed between 600m V and 3.775V in 25m V steps (Type B). All four regulators operate independently and can be put into pulse skip, LDO, Burst Mode operation, or forced Burst Mode operation through I2C control. The Type-A regulators have separate RUN pins that can be enabled if I2C control is unavailable. The 2.85V to 5.5V input voltage range makes the LTC3562 ideally suited for single Li-Ion battery-powered applications. At low output load conditions, the regulators can be switched into LDO, Burst Mode operation, or forced Burst Mode operation, extending battery life in portable systems. The quiescent current drops to under 100μA with all regulators in LDO mode, and under 0.1μA when all regulators are shut down. Switching frequency is internally set to 2.25MHz,...