ILC6390

Impala Linear Corporation ILC6390/91 SOT-89 Step-Up PFM Switcher with Auto-Load Sense General Description 50 mA boost converter using Pulse Frequency Modulation, or PFM, technique, in 5-lead SOT-89 or a 5-lead SOT-23 package. Only 3 external components are needed to complete the switcher design. The ILC6390 automatically senses load variations to choose between 55% and 75% duty cycles. Normal operation is 55% duty at 155kHz; when load currents exceed the internal comparator trip point, a “turbo mode” kicks in to provide extended on-time switching (75% duty at 100kHz oscillation). Requiring only 30µA of supply current, the ILC6390 achieves efficiencies as high as 85% at 5V yet shuts down to 0.5µA max. Standard voltages offered are 2.5, 3.3, and 5.0V and is available in both a 5 lead SOT-23 and 5 lead SOT-89 package for small footprint applications. In addition, the ILC6391 is configured to drive an external transistor to achieve higher power levels. Features 85% conversion e...